Copyright: ArcGIS 8.1                                                  Copyright © 1982-2001 ESRI, Inc.


This help file is part of the context-sensitive help system for the commands and controls in the ArcMap and ArcCatalog applications.

The topics in this help file can only be accessed via the context-sensitive help controls in the applications.

Here's how you access context-sensitive help from within ArcMap or ArcCatalog:

-	To get help on a pulldown menu command or toolbar button, click the "What's This?" Help tool in the Standard toolbar and then click the command or button.

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Add COGO Items

Adds empty coordinate geometry (COGO) attributes to a line coverage arc attribute table (AAT):

ANGLE is the direction of two-point lines or the chord direction of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves. (item width: 10; display width: 10; item type: C).

DISTANCE is the length of two-point lines or the chord length of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves. (item width: 8; display width: 8; item type: C).

RADIUS is the circular curve radius or the first radius of a spiral. This item is needed when working with working with circular curves and spiral curves (item width: 8; display width: 8; item type: C).

DELTA is the delta angle of a circular curve or spiral. This item is needed when working with working with circular curves (item width: 10; display width: 10; item type: C).

TANGENT is the tangent length of a circular curve or the first tangent length of a spiral. (item width: 8; display width: 8; item type: C).

ARCLENGTH is the arc length of a circular curve or spiral. This item is needed when working with working with circular curves and spiral curves. (item width: 8; display width: 8; item type: C).

SIDE is the right or left side where the radius point for curves or radius points for spirals are located with respect to the circular curve or spiral. This item is needed when working with circular curves and spiral curves. (item width: 1; display width: 1; item type: C).

RADIUS2 is the second radius of a spiral. This item is needed when working with spiral curves. (item width: 8; display width: 8; item type: C).

TANGENT2 is the second tangent length of a spiral. (item width: 8; display width: 8; item type: C).

Notes

The tool does not calculate the COGO attributes for two-point lines and curves, it only adds empty COGO attribute items to the coverage AAT. If you have an arc coverage that you want to attach calculated COGO attributes to existing two-point lines and curves, then use the Calculate COGO Attributes tool.

The COGO application allows you to work with a minimum set of attributes. For example, to work with:

Two-point lines, you need only the items ANGLE and DISTANCE.

Circular curves, you need only the items ANGLE, DISTANCE, RADIUS, ARCLENGTH, and SIDE.

Spiral curves, you need only the items ANGLE, DISTANCE, RADIUS, ARCLENGTH, SIDE, and RADIUS2.

Delete unwanted attributes in ArcCatalog.

Related Topics


The coverage to which you want to add COGO attributes.


Add a Custom Tool
Add Custom EXE Wizard

A custom tool is one whose functionality is currently not included in the ArcToolbox’s toolset and that you often use in your GIS work. For example, you might need a Describe tool because you want to view details about a geodataset. Or you might add a tool that runs an AML to string two or more tools together, such as projecting a dataset to the State Plane Coordinate System and then re-creating topology with Build. Other examples are a small program that calculates your weekly work hours by project number, a more elaborate program that does the same thing for all people you supervise, and a large program such as ArcInfo’s Arc module, ArcMap, and other program executables. The Add Custom EXE Wizard steps you through adding your tool to the ArcToolbox.

Notes

The Custom tool must be self-contained, i.e., it must provide its own validation and error handling.

The Custom tool must be stable and robust to work smoothly with the ArcToolbox.


Choose a tool to add to the ArcToolbox

An executable must operate in the current operating environment and provide its own error handling and validation routines. For example, you can add ArcCatalog or ArcMap as a custom tool by specifying either application’s .exe, stored in the ARCHOME_USER\bin directory.


No help available (ArcToolbox 9999999)


Add from ASCII

Appends attribute records from an ASCII file to a table. The ASCII file must meet the following requirements:

Commas separate item values.

Character strings must be enclosed with single quotes if they contain embedded blanks.

Dates must be enclosed with single quotes and correspond to this format: '05/06/1998'.

Item values must match the item definitions in the Input table.

Values for all items must be provided in the order they appear in the table.

The ASCII file can be created with a text editor like Notepad, a spreadsheet program such as Excel, a statistical program such as Systat, or with the ArcInfo TABLES command UNLOAD.

Notes

The tool verifies that the ASCII file is in the same format as the Input table. But the item width and the number of decimal places are not verified for numeric and floating point items. Values that exceed the item width or the number of decimal places are truncated.

In the ASCII file, two commas with no space between them skip an item and assign the value to Null.

Items that have not received a value at the end-of-record are assigned a value of Null.

Sample comma-delimited ASCII file

Related Topics


Choose the table you want to add records to.


The ASCII file containing the records you want to add to the Input table.


Sample comma-delimited ASCII file

test1,4,6.8,'not ok','05/06/98'
test2,5,4.5,ok,'05/06/98'
test3,6,0.2,ok,'05/06/98'
test4,7,6.03,'not ok','05/06/98'
test5,1,5.70,ok,'05/06/1998'
test6,2,10.60,ok,'05/06/1998'


ADDXY
ADD XY Coordinates

Adds the items X-COORD and Y-COORD for labels or points to the Input coverage PAT or for nodes to the Input coverage NAT and calculates their values.

The tool determines the Input coverage’s Feature classes and lists those available to add x, y coordinates to. The tool is most commonly used to get access to a coverage’s geometry to perform queries and analysis, or to extract points or nodes based on their x, y location.

Notes

If the items X-COORD and Y-COORD already exist, then they will be overwritten.

If the Input coverage is single precision, the items will be defined with Item width 4, Display width 12, Item type F, and Decimal places 3. If the Input coverage is double precision the items are defined with Item width 8, Display width 18, Item type F, and Decimal places 5. Once defined, this definition will not change even if the precision is changed.

If the point or node locations are moved after using the Add XY Coordinates tool, the X-COORD and Y-COORD values will not represent the new locations. To update their values to the new location, rerun the tool.

If your Input coverage is in geographic coordinate system, the X-COORD and Y-COORD represents the longitude and latitude, respectively.


The coverage whose feature attribute tables you want to add x,y coordinates.


The feature class to which you will add x,y coordinates.

Point – adds or updates the items X-COORD and Y-COORD in the PAT.

Node – adds or updates the items X-COORD and Y-COORD in the NAT.


Adjust

Adjusts or rubber sheets the features of a coverage or grid in either direction along the links from a link coverage or link file. Links are used to ‘rubber sheet’ the coverage or grid feature coordinates. Links represent the from- and to- locations used in the adjustment; after Adjust they still represent the same locations.

During adjustment, the coverage or grid surface is stretched using the links as displacement vectors. All from- locations on the links adjust to the to- locations. With Adjust links in reverse checked, the directions of links are flipped. Then the adjustment is performed in the opposite direction: from the to- locations to the from- locations.

All coordinates of all coverage feature types are adjusted, including arcs, label points, annotation, and tics (if Adjust tics is checked). If the Link dataset is the same as the Input dataset, or if the Input dataset has links, links remain as links.

Notes

The Link dataset must be in the same coordinate system (i.e., projection and datum) as the Input dataset. You must have at least 4 links.

When performing rubber sheeting, it is important to have links spread systematically over the entire coverage or grid including along the outer edges. The further away a coordinate is from a link, the less effect that link has on the coordinate’s adjustment. It is important that the adjustment be systematic and that equal weight be given to the adjustment of all areas in the coverage or grid.

If there are feature coordinates that fall outside the adjustment area (or convex hull of all coverage links), they are not adjusted. The convex hull is created by connecting the outer boundary of the from-points of links.

Adjust has a limit of 50,000 links in the Link dataset.

One of the major uses for Adjust is to perform datum conversions. Coordinate values for each from- and to- point are referenced in degrees of latitude and longitude. Thus, the datum adjustment must be performed with an Input dataset having geographic coordinates referenced in degrees of latitude and longitude. For a complete description of the datum adjustment process, refer to ArcDoc: ARC/INFO Concepts->Map Projections->Datums and datum conversion.

Route-systems and region subclasses of the input coverage are maintained. The projection file (PRJ) of an input coverage or grid is also maintained.

Example link file

Related Topics


Example link file

Each line in the ASCII file represents a link. Imagine a link to be a two point line segment represented by the start coordinate followed by the end coordinate. In the link file below, the first line represents a link that begins at (0,0) and ends at (1,1). Remember that you must have at least 4 links to run Adjust.

0 0 1 1
10 0 10 2
9 9 10 10
0 10 0 11


The coverage or grid to be adjusted.


Choose how the coordinate adjustment is to be performed.

From link coverage – a coverage containing links (control points). This can be the same coverage as Input dataset.

From link file – an ASCII file containing links (control points).


The link coverage or link file that provides the control points for the coordinate adjustment.


Choose which direction to make the adjustment.

Unchecked – adjustment occurs in the normal direction along each link, adjusting the from-point to the to-point on each link.

Checked - links are reversed for the adjust. Adjustment then takes place by adjusting from the to-point to the from-point on each link.


Choose whether to adjust tics.

Unchecked – tics will not be adjusted.

Checked - tics will be adjusted.


The resampling algorithm that specifies how the output cell value is computed from input cell values after a cell is transformed (adjusted). This is used only with input grids, not coverages.

Nearest neighbor – calculates the value of each output cell by assigning it the value of the closest cell center in the input grid. This method does not change any of the values of cells from the input grid. Use this method with for nominal or ordinal data, where each value represents a class, member, or classification, and for categorical or integer data (i.e., a landuse, or a soil or forest type).

Bilinear interpolation – identifies the four nearest input cell centers to the location of the center of an output cell on the input grid. The new value for the output cell is a weighted average determined by the value of the four nearest input cell centers and their relative position or weighted distance from the location of the center of the output cell in the input grid. Since the values for the output cells are calculated according to the relative position and the value of the input cells, the bilinear interpolation is preferred for data where the location from a known point or phenomenon determines the value assigned to the cell (i.e., continuous surfaces). Elevation, slope, intensity of noise from an airport, and salinity of the groundwater near an estuary are all phenomenon represented as continuous surfaces and are most appropriately resampled using bilinear interpolation.

Cubic convolution – uses the 16 nearest input cell centers and their values to determine the output cell value. A smooth curve is fitted through the points to find the value at the output cell center. It is not a weighted average of the input cells, with the result that the output cell value may in some cases lie outside the range of values of the input cells. Cubic convolution tends to smooth the data more than bilinear interpolation, because of the smooth curves used as well as the larger number of points involved.

Note: Bilinear interpolation or cubic convolution should not be used on categorical data since the categories will not be maintained in the output grid. However, all three techniques can be applied to continuous data, with the nearest neighbor producing the more blocky output and the cubic convolution the smoothest.


The transformation method to be used for calculating cell values when adjusting a coverage or grid. Adjust builds a tin from the Link dataset to find the coordinate transformation from input points to the adjusted points. Bivariate and Linear refer to how the coordinate transformation is calculated from tin triangles.

Bivariate – bivariate transformation. In general, Bivariate gives better results.

Linear – linear transformation. In general, Linear is faster.


The coverage or grid you will create.


ADRG to Grid

Converts ADRG data into a grid or grid stack.

The ALL option for Input band(s) creates a grid stack composed of one grid for each ADRG band. Stack names are limited to a maximum of 9 characters.

You can convert a single band by selecting its number from the Input band(s) list.

Notes

ADRG data are multiband images supplied on CD-ROM from the National Imagery and Mapping Agency (formerly Defense Mapping Agency).

Images in non-polar regions use the geographic reference system with units in decimal seconds. Polar regions use an Azimuthal Equidistant projection with units in meters. Both regions use the WGS84 datum.

Supported file extension

About ADRG data


The ADRG file you want to convert to a grid or grid stack.


The grid or grid stack you will create.

NOTE: Stack names can only be 9 characters long.


Select the image band you want to convert to a grid.

ALL – creates a grid for each available image band and combines them to a grid stack.

1 – creates a grid from band 1 (red) image data.

2 – creates a grid from band 2 (green) image data.

3 – creates a grid from band 3 (blue) image data.


 Choose how much of the image to convert.

Full extent – converts the entire image.

Clip to box – converts only the image part inside the box defined below.


The area covered by the image.


The area covered by the grid(s) you will create.


About ADRG data

Arc Digitized Raster Graphics (ADRG) data is created by the United States National Imagery and Mapping Agency (NIMA; formerly the United States Defense Mapping Agency(DMA)) and distributed on CD-ROM. ADRG is geographically referenced using the equal arc-second raster chart/map (ARC) system in which the globe is divided into 18 latitudinal bands or zones. The data consists of raster images and other graphics generated by scanning source documents.

On 01 December 1997 NIMA gave its “Notice of Inactivation” for ADRG data. The format is no longer used, except in existing systems.

ADRG data can be displayed directly in ArcInfo, or it can first be converted to grid format and then viewed in the Grid module.

ADRG file description

 	ADRG directory structure

ADRG to Grid output

ADRG sample file


ADRG file descriptions:

An ADRG directory typically stores many image datasets. The following list of images that can all be used with ArcInfo provides an overview: The following is a discussion of this directory structure.

Transmittal header file (.THF) - contains data describing the contents of the CD-ROM. This file is needed to convert or display the test patch image file.

Test patch image file (.CPH) - image derived from a standard graphic arts color control patch. Can be used as the Input ADRG file.

General Information file (.GEN) - general information to support the overview and ZDR images. This file is needed to convert or display the overview image file or the geo data file.

Quality file (.QAL) - contains the horizontal and vertical accuracies of the images. This file is not used by ArcInfo.

Overview image file (.OVR) - reduced resolution image of a distribution rectangle (DR). Can be used as the Input ADRG file or displayed with the IMAGE command.

Geo data file (.IMG) - full resolution image of a zone within the distribution rectangle (ZDR). Can be used as the <in_image> or displayed with the IMAGE command.

Source file (.SOU) - contains information on the source graphic for the ZDR image. This file is needed to convert or display a legend image file.

Legend image file (.Lgg, where gg are numbers) - zero or more images of selected margin information. Can be used as the Input ADRG file.

References

MIL-A-89007: Arc Digitized Raster Graphics (ADRG). United States Defense Mapping Agency, 1990.


ADRG directory structure

References

MIL-A-89007: Arc Digitized Raster Graphics (ADRG). United States Defense Mapping Agency, 1990.


ADRG to Grid output

This example shows the conversion of part of one band of the ADRG data tpeg0101.ovr.

Description of GridTPEG created with the ADRG to Grid tool:

Cell Size =	25.895	Data Type:	Integer

Number of Rows =	772	Number of Values =	248

Number of Columns = 	386	Attribute Data (bytes) =	8

BOUNDARY	STATISTICS

Xmin =	90000.000	Minimum Value =	 	000

Xmax =	99995.524	Maximum Value =	55.000

Ymin =	80000.000	Mean =	940

Ymax =	99991.049	Standard Deviation =	105.263

COORDINATE SYSTEM DESCRIPTION

Projection 	GEOGRAPHIC

Datum	WGS84

Units	DS

Spheroid	 	WGS84

Parameters:

References

MIL-A-89007: Arc Digitized Raster Graphics (ADRG). United States Defense Mapping Agency, 1990.


ADRG sample file

Description of the ADRG image tpeg0101.ovr

Image Format :	ADRG	Image Depth =	8

Image Type :	MULTIBAND	Image Bands =	3

Image Colormap :	FALSE	Number of Columns = 	1024

Image Compressed :	FALSE	Number of Rows =	1024

Image Rotated :	FALSE	Pixel Size DX = 	28.047

Pixel Size DY = 	25.895

BOUNDARY 	STATISTICS

Xmin =	82556.606	No statistic information available

Ymin =	76248.234

Xmax = 	111276.828

Ymax =	102764.858

NO COORDINATE SYSTEM DEFINED

References

MIL-A-89007: Arc Digitized Raster Graphics (ADRG). United States Defense Mapping Agency, 1990.


 A grid stack is a collection of ordered grids. The stack stores both the location and order of the grids. The grids are assumed to be in the same coordinate system and have some spatially coincident area. A stack is treated as a single entity for multivariate analysis. The GRID functions to perform cluster analysis, classification, and principal component analysis all take a grid stack as input.


Arc Digitized Raster Graphics (ADRG) data is created by the United States National Imagery and Mapping Agency (NIMA; formerly the United States Defense Mapping Agency(DMA)) and distributed on CD-ROM. ADRG is geographically referenced using the equal arc-second raster chart/map (ARC) system in which the globe is divided into 18 latitudinal bands or zones. The data consists of raster images and other graphics generated by scanning source documents.

NOTE: As of 01 December 1997 ADRG data is no longer distributed and used, except in existing systems.


AGF to Shapefile

Converts an Atlas Geo file (AGF) into an ESRI shapefile.

This tool does not support remote processing using a Geoprocessing Server. The tool is always run with a local processing state.

Notes

The general procedure is to determine which layer of the Atlas Geo file to translate and then convert that particular layer to an ESRI shapefile. Unlike Atlas Geo files, ESRI shapefiles contain only one layer of spatial information.

Although you can convert an Atlas Geo file that is in any projection, we recommend that you always put the Atlas Geo file into the Latitude/Longitude projection first. Within Atlas GIS for Windows, go to the Map pull down menu, select Change Projection and then LL. When the Atlas Geo file is in Latitude/Longitude, the shapefile coordinates will be written in decimal degrees. Decimal degrees are preferred for ESRI shapefiles since ArcView can project them to other projections on the fly. As a result, shapefiles are generally stored in decimal degrees.

The projection information of the AGF file is written to an ArcInfo projection file (PRJ) for most projections; the exceptions are GKn, IGNxxx, LLPARIS, OSGB, and OSNI. The PRJ file will have the same name as the shapefile (i.e. XXX.PRJ). If ArcInfo users later convert the shapefile to a coverage, they should copy the PRJ file into the coverage directory as ‘prj.adf’ so the coverage will have the correct projection information.

When creating a shapefile, the resultant DBF file will have the following items:

ID_	The ID of the feature.

NAME1_	The primary name of the feature.

NAME2_	The secondary name of the feature.

For line and region layers.

PARTS_	The number of lines or polygons that make up the feature.

POINTS_	The number of points in the feature.

LENGTH_	The length of the line or perimeter of the polygon.

For region layers.

AREA_	The area of the polygon.

Supported file extension

Related Topics


The AGF file you want to convert to a shapefile.


The shapefile you want to create.


The layers contained within the Input AGF file. Only one layer may be converted to a single shapefile.


An alphabetical list of ArcToolbox tools

Tool name	Description (Arc command)

A

Add a Custom Tool Wizard	adds a custom tool to the ArcToolbox.

Add COGO Items	adds empty COGO attributes to a line coverage (ADDCOGOATT).

Add from ASCII	appends attribute records to a table from an ASCII file (ADD).

ADRG to Grid	converts a US NIMA ARC Digitized Raster Graphics (ADRG) image into a grid or stack of multiple grids (ADRGGRID).

AGF to Shapefile	converts an Atlas Geo file (AGF) to a shapefile.

Append Wizard	combines up to 500 adjacent coverages into one coverage (APPEND, MAPJOIN).

ASCII to Grid	converts an ASCII file to a grid (ASCIIGRID).

B

Buffer	creates a polygon coverage of buffers surrounding features in a point, node, line or polygon coverage (BUFFER).

Buffer Regions	creates buffer regions around grouped input coverage features (REGIONBUFFER).

Buffer Wizard	leads you through the process of buffering specified input coverage features (BUFFER, REGIONBUFFER).

Build	creates or updates feature attribute tables and polygon and/or arc-node topology (BUILD).

Build Geometric Network Wizard	builds network topology for geodatabase feature classes.

C

Calculate COGO Attributes	calculates COGO attribute values for two-point lines and curves (ARCCOGO).

Calculate Legal Area	computes the legal area, legal perimeter, and closure error for parcels, using COGO attributes (LOTAREA).

Centroid Labels	moves a polygon’s label point to its center (CENTROIDLABELS).

Clean	generates a coverage with correct polygon or arc-node topology (CLEAN).

Clean Regions	simplifies a region coverage by merging polygons and duplicate arcs not needed to define regions, using one or more selection expressions (REGIONCLEAN).

Clip	uses the outside polygon boundary of a clip coverage to cookie-cut features and attributes from an input coverage (CLIP).

Contour Wizard	converts a tin or grid to a coverage containing contours or isolines (LATTICECONTOUR, TINCONTOUR).

Copy Items	copies selected items to a new table (PULLITEMS).

Coverage to DFAD	converts an entire workspace containing ArcInfo coverages to a single DFAD transfer file (ARCDFAD).

Coverage to DIME	converts the arcs in a line or polygon coverage to a DIME file in the standard U.S. Census Bureau, 300-character ASCII format (ARCDIME).

Coverage to DLG	creates a DLG-3 Optional format file from ArcInfo coverages (ARCDLG).

Coverage to DXF	converts ArcInfo coverages into an AutoCAD Drawing Interchange File (ARCDXF).

Coverage to Generate File	creates a text file of x,y coordinates for a coverage. (UNGENERATE).

Coverage to Geodatabase	converts ArcInfo coverage features into a geodataset feature class.

Coverage to Geodatabase Wizard	A wizard that converts ArcInfo coverage features into a geodataset feature class.

Coverage to IGDS Wizard	converts a coverage into IGDS format (ARCIGDS).

Coverage to IGES	converts an ArcInfo coverage into an Initial Graphics Exchange Standard (IGES) Version 3.0 uncompressed ASCII file (ARCIGES).

Coverage to Interchange File	converts a coverage, file or other supported data set to an interchange file for transfer to another platform (EXPORT).

Coverage to MOSS	converts a coverage to a MOSS export file (ARCMOSS).

Coverage to SDTS	creates an SDTS Topological Vector Profile (TVP) transfer from ArcInfo coverages (SDTSEXPORT).

Coverage to Shapefile	writes feature attributes or INFO records to a new shape data file (ARCSHAPE).

Coverage to SLF	converts an ArcInfo coverage to a Standard Linear Format (SLF) file (ARCSLF).

Coverage to VPF	converts an INFO table into a VPF table or an ArcInfo coverage into either a VPF coverage or VPF tile (VPFEXPORT).

Create Centerlines	creates centerlines from dual-line features based on specified width tolerances (CENTERLINE).

Create COGO Coverage	creates a new line coverage with COGO attributes or a point coverage (CREATECOGO).

Create Polygon Labels	creates polygon label points (CREATELABELS).

Create Thiessen Polygons	converts input coverage points to a coverage of Thiessen proximal polygons (THIESSEN).

Create Tin Wizard	creates a tin from one or more coverages or generate files (CREATETIN).

Create VPF Tile Topology	converts an INFO table into a VPF table or an ArcInfo coverage into either a VPF coverage or VPF tile (VPFTILE).

Cut & Fill	summarizes the areas and volumes of change during a cut-and-fill operation on an area represented by two grids, one before and one after the cut-and-fill operation (CUTFILL).

D

dBASE to INFO	copies a dBASE data table into an INFO data file (DBASEINFO).

DBMS to INFO	converts a DBMS table or view to an INFO table (DBMSINFO).

Define Projection Wizard	defines the projection for a geodataset or applies the projection definition of one geodataset to another one (PROJECTCOMPARE, PROJECTCOPY, PROJECTDEFINE).

Define Table	creates a table and defines its items (DEFINE).

DEM to Grid	converts a DEM in USGS format to a lattice. A lattice is essentially the same as a grid, providing the same functionality (DEMLATTICE).

DFAD to Coverage	converts a DFAD transfer file to a set of coverages (DFADARC).

DIME to Coverage	converts a DIME file to a line coverage and an ACODE attribute file containing DIME field attributes (DIMEARC).

Dissolve	simplifies a coverage by eliminating nodes along connected lines, or arcs between adjacent polygons, that have the same Dissolve item value (DISSOLVE).

Dissolve Regions	constructs new region subclasses by aggregating polygons or regions with the same value for a specified item (REGIONDISSOLVE).

DLG to Coverage Wizard	converts a Digital Line Graph (DLG) file in either Standard or Optional format into ArcInfo coverages (DLGARC).

DTED to Grid	converts a United States National Imagery and Mapping Agency Digital Terrain Elevation Data (DTED) file into a grid (DTEDGRID).

DXF to Coverage Wizard	converts an AutoCAD Drawing Exchange File (DXF) to a double-precision coverage (DXFARC).

E

Eliminate	removes polygons or lines from a coverage by merging them with adjacent features (ELIMINATE).

Erase	creates a new coverage by overlaying the polygons of the erase coverage with the features of the input coverage (ERASE).

Etak to Coverage	converts an Etak MapBase file to a coverage (ETAKARC).

Export to Interchange File	converts a coverage, file or other supported data set to an interchange file for transfer to another platform (EXPORT).

Export to SDTS	creates an SDTS Topological Vector Profile (TVP) transfer from ArcInfo coverages and grids(SDTSEXPORT).

Extract Wizard	guides you through the process of extracting features from a single or multiple coverages (AREAQUERY, REGIONQUERY, RESELECT).

F

Feature Class to Geodatabase	converts a geodatabase feature class to another geodatabase.

Find Building Conflicts	finds where buildings overlap or are too close to each other, based on a specified distance (FINDCONFLICTS).

Floating Point Data to Grid	converts an IEEE floating point format, 32-bit signed file of binary floating point numbers into a grid (FLOATGRID).

Frequency	searches an input table for unique occurrences of one or more items (FREQUENCY).

G

Generalize Lines	reduces details from lines and polygon boundaries based on a specified tolerance and simplification method (GENERALIZE).

Generate to Coverage Wizard	converts an ASCII file to a coverage or adds features to an existing coverage (GENERATE).

Geodatabase to Coverage	converts a geodatabase feature class to a coverage.

Geodatabase to Shapefile	converts a geodatabase feature class into a shapefile.

Geodatabase to Table	converts a geodatabase table into a DBASE or INFO table.

Grid to ASCII	converts an integer or floating point grid to an ASCII file (GRIDASCII).

Grid to DEM	converts an ArcInfo grid to a Digital Elevation Model in the United States Geological Survey (USGS) format (LATTICEDEM).

Grid to Floating Point Data	converts grid cell values to a signed, 32-bit, binary file in IEEE floating point format suitable for data transfer to other applications (GRIDFLOAT).

Grid to Image	converts a grid to a single-band image, or a grid stack to a multi-band image (GRIDIMAGE).

Grid to Interchange File	converts a grid, coverage, or other supported data set to an interchange file for transfer to another platform (EXPORT).

Grid to Line Coverage	converts a grid representing raster linear features to a line coverage (GRIDLINE).

Grid to Point Coverage	converts a grid representing raster point features to a point coverage (GRIDPOINT).

Grid to Polygon Coverage	converts a grid to a polygon coverage. Polygons are built from groups of contiguous cells having the same cell values (GRIDPOLY).

Grid to SDTS	creates an SDTS Topological Vector Profile (TVP) transfer from ArcInfo coverages (SDTSEXPORT).

Grid to Tin	converts a grid to a tin (LATTICETIN).

H

I

Identity	computes the geometric intersection of two coverages.  All features of the input coverage, as well as those features of the identity coverage that overlap the input coverage, are preserved (IDENTITY).

IGDS to Coverage Wizard	converts an Interactive Graphics Design Software (IGDS) file into a coverage (IGDSARC, IGDSINFO).

Image to Grid	converts an image into a grid or set of grids (IMAGEGRID).

Import from Interchange File	converts an ArcInfo export interchange file to a coverage, grid, or other supported data set (IMPORT).

Import SDTS Wizard	creates ArcInfo coverages or grids from either a SDTS Topological Vector Profile (TVP), Point Profile or Raster Profile transfer (SDTSIMPORT).

INFO to dBASE	converts an INFO table to a dBASE table (INFODBASE).

INFO to DBMS	converts an INFO table to a DBMS table (INFODBMS).

INFO to Interchange File	converts an INFO file, coverage, or other supported data set to an interchange file for transfer to another platform (EXPORT).

Interchange File to Coverage	converts an ArcInfo export interchange file to a coverage or other supported data set (IMPORT).

Interchange File to Grid	converts an ArcInfo export interchange file to a grid or other supported data set (IMPORT).

Interchange File to INFO	converts an ArcInfo export interchange file to an INFO file or other supported data set (IMPORT).

Interchange File to Tin	converts an ArcInfo export interchange file to a tin or other supported data set (IMPORT).

Intersect	computes the geometric intersection of two coverages. Only those features in the area common to both coverages will be preserved in the output coverage (INTERSECT).

J

Join Tables	joins two tables based on a relate item (JOINITEM).

K

L

Line Coverage to Grid	converts a line coverage to a grid (LINEGRID).

Line Coverage to Region	converts arcs to preliminary regions or appends preliminary regions to the specified region subclass (REGIONCLASS).

Line Coverage to Route	creates a route system from lines or appends lines to a route system (ARCROUTE).

M

MIF to Shapefile	converts a Mapinfo Interchange Format (MIF) file into a shapefile.

MOSS to Coverage	converts a file in MOSS export format into an ArcInfo coverage (MOSSARC).

N

Near	computes the distance from every input coverage point to the nearest point, line or node in another coverage, within the maximum search radius (NEAR).

O

OLE DB to Table	converts OLE DB tables to dBASE or INFO tables.

Overlay Wizard	creates a new coverage by computing the geometric intersection of two coverages (IDENTITY, INTERSECT, UNION).

P

Point Coverage to Grid	converts a point coverage to a grid (POINTGRID).

Point Distance	computes the point-to-point distance between each point in a coverage to points in another coverage, within a maximum search radius (POINTDISTANCE).

Point Node	transfers attributes from a point feature class to a node feature class (POINTNODE).

Polygon Coverage to Grid	converts a polygon coverage to a grid (POLYGRID).

Polygon Coverage to Region	converts a polygon coverage to a region subclass. Each polygon in the Input coverage becomes a region of the output subclass (POLYREGION).

Project Wizard	Converts a geodataset between two coordinate systems (PROJECT).

Q

Query Regions	creates new regions based on the attribute values of input region or polygon layers and aggregates regions according to specified attribute items (REGIONQUERY).

R

Region to Polygon Coverage	converts a region subclass to a polygon coverage and creates a table with data on overlapping regions (REGIONPOLY).

Renumber Nodes	updates arc-node topology by renumbering From- and To- nodes (RENODE).

Run Geoprocessing AML	 executes an AML (&RUN).

S

SDTS to Coverage Wizard	creates ArcInfo coverages or grids from either a SDTS Topological Vector Profile (TVP), Point Profile or Raster Profile transfer (SDTSIMPORT).

SDTS to Grid Wizard	creates ArcInfo coverages or grids from either a SDTS Topological Vector Profile (TVP), Point Profile or Raster Profile transfer (SDTSIMPORT).

Select	extracts selected features from an input coverage and stores them in an output coverage (RESELECT).

Shapefile to AGF	creates an AGF file from a shapefile.

Shapefile to Coverage	writes shapefile spatial and attribute information to an ArcInfo coverage (SHAPEARC).

Shapefile to Geodatabase	writes shapefile spatial and attribute information to an geodatabase feature class.

Shapefile to Geodatabase Wizard	a wizard to write shapefile spatial and attribute information to a geodatabase feature class.

Simplify Buildings	simplifies building boundaries (BUILDINGSIMPLIFY).

SLF to Coverage	converts a Standard Linear Format (SLF) file to an ArcInfo coverage (SLFARC).

Split	clips portions of the Input coverage into multiple coverages (SPLIT).

Statistics Wizard	a wizard to perform attribute statistics (FREQUENCY, STATISTICS).

Summary Statistics	generates summary statistics for items in an INFO table and saves them in an output INFO table (STATISTICS).

T

Table to Geodatabase	converts INFO or dBASE tables to a geodatabase table.

TIGER to Coverage Wizard	converts a set of U.S. Bureau of Census TIGER/Line files into one or more ArcInfo coverages (TIGERARC).

Tin to Coverage	converts a tin to a coverage (TINARC).

Tin to Grid	converts a tin to a grid (TINLATTICE).

Tin to Interchange File	converts a coverage, file or other supported data set to an interchange file for transfer to another platform (EXPORT).

Tin to VRML	converts a tin to VRML format (TINVRML).

Transform	scales, skews, rotates, and shifts coverage coordinates using an affine, similarity or projective transformation based on a set of tics (TRANSFORM).

U

Union	creates a new coverage by overlaying the polygons in the union coverage with those in the input coverage (UNION).

Update	creates a new coverage by overlaying two sets of features, using the polygons of the update coverage to cookie-cut the features and attributes from the input coverage (UPDATE).

Update IDs	updates User-IDs in a coverage after they have been modified in a feature attribute table (IDEDIT).

V

Visibility	performs visibility analysis on a grid by determining how many observation points in a coverage can be seen from each region of the grid, or which regions can be seen by each observation point (VISIBILITY).

Volume	calculates the area and volume of a tin (VOLUME).

VPF to Coverage	converts a VPF table into an INFO table or it converts either a VPF coverage or VPF tile into an ArcInfo coverage (VPFIMPORT).

W

X

Y

Z


Append Wizard

Merges features from two or more coverages into a single coverage, both horizontally and vertically. It rebuilds topology only for the feature classes Poly or Poly & Line (Net), but not for any other.

When the Coverages to be appended are adjacent, they should meet accurately at their shared boundaries such that the arc coordinates that define the common boundary are the same for both coverages. Equally important, arcs that meet at borders between adjacent coverages should match. Polygon codes should be the same if a polygon extends into an adjacent coverage. To view an example, click [image].

The option Append all features but not feature attributes lets you merge different feature types (e.g., points from one coverage and arcs from another). Only coordinates are appended; feature attribute tables are neither appended nor are they copied. If you want to merge feature attributes in the Output coverage after using this option, do not create Unique IDs for features in the Select the output coverage panel. After the wizard has executed, you can use the Join Tables tool to merge attributes from the input coverage feature attribute table into the Append Wizard Output coverage.

Recommended post-processing

Coverages created with the Append Wizard generally require further processing before they can be used as input with other tools. These include:

Splitting intersecting arcs (Clean).

Edgematching arcs that cross over adjacent coverage boundaries (ARC MATCHNODE or Link coverages in ArcEdit).

Removing sliver polygons or boundaries between adjacent coverages (e.g., by Eliminate, Select or Dissolve).

Removing dangling arcs (Clean).

Matching nodes (ARC SNAPCOVER, MATCHNODE or ArcEdit).

Dissolving interior boundaries between adjacent coverages (Dissolve).

Building topology (Clean or Build).

Related Topics


Feature classes

The wizard determines the available feature classes from the input coverages. The list includes one or more of the following. Check the box of those you want to append.

Poly – polygon feature coordinates and attributes are joined, including label points. Polygon topology is rebuilt.

Poly & Line (Net) – polygon and arc feature coordinates and attributes are joined. Polygon topology is rebuilt.

Line – arc feature coordinates and attributes are joined.

Node – node feature coordinates and attributes are joined.

Anno.<subclass> – annotation features and attributes of subclass are joined.

Section.<subclass> – section feature coordinates and attributes of the subclass are joined.

Route.<subclass> – route feature coordinates and attributes of the subclass are joined.

Region.<subclass> – region feature coordinates and attributes of the subclass are joined. Polygon feature coordinates and attributes are also joined.


Create unique IDs

This option lets you assign unique User-IDs to tics, features, or both, in the Output coverage using a standard offset value of 1. Before a coverage is appended, unique IDs are calculated as 1 plus the largest User-ID value for the specified feature class that has so far been written to the Output coverage. The offset value is then added to each feature User-ID in the appended coverage; thus, the Output coverage User-ID = input coverage User-ID + offset. NOTE: Unique IDs are not assigned to the first input coverage.

No – User-IDs will not be modified. This is the default option.

Tics only – Unique IDs will be assigned to tics only.

Features only – Unique IDs will be assigned to the selected feature classes only.

Tics and features – Unique IDs will be assigned to tics and features.

If you choose the No option and your appended coverages contain duplicate Tic-IDs, any previously encountered Tic-ID will not be written to the Output coverage. This may be useful when each tic in the study area has been digitized with one unique Tic-ID. If the feature attribute tables of the appended coverages contain duplicate User-IDs, the Output coverage will also contain duplicate User-IDs for arcs or label points.

Example of unique Tic-ID assignment for three coverages

For all coverages appended after the first, the assignment is 1 plus the highest Tic-ID value used so far.

              Tic-IDS          Tic-IDS         Unique ID
           before Append    after Append       Assignment

1st coverage     4              4             No assigment
                 9              9
                11             11
                 5              5
2nd coverage     8             20             11 + 1 = 12
                 2             14
                 5             17
                 3             15
3rd coverage     3             24             20 + 1 = 21
                 4             25
                 5             26
                 6             27


Three important edgematching checks which should be performed to ensure correct appending of adjacent coverages.


ASCII to Grid

Converts an ASCII file to a grid. The ASCII file must consist of header information containing a set of keywords, followed by cell values in row-major order.

Header format and description

Notes

A carriage return is not necessary at the end of each grid row because the number of columns (NCOLS) in the header is used to determine when each new row begins. Therefore, the total number of values must be equal to the number of columns times the number of rows.

You can specify the location of the grid’s origin (lower-left corner) using the coordinates of either its lower-left corner (XLLCORNER/YLLCORNER) or the center of the lower-left grid cell (XLLCENTER/YLLCENTER).

The keyword NODATA_VALUE is optional; it defaults to -9999.

Sample listing of an ASCII file

Supported file extension

Related Topics


The value 'Nodata' or ‘-9999’ is assigned to the 'NODATA_VALUE' item for cells whose value is unknown.


Sample listing of an ASCII file suitable for conversion to a grid

NCOLS 480
NROWS 450
XLLCENTER 378923
YLLCENTER 4072345
CELLSIZE 30
NODATA_VALUE –32768
43 2 45 7 3 56 2 5 23 65 34 6 32 54 57 34 2 2 54 6
35 45 65 34 2 6 78 4 2 6 89 3 2 7 45 23 5 8 4 1 62  ...


The ASCII file you want to convert to a grid.


The grid you will create.


Choose the data type for your output grid:

Integer – creates a grid with integer cell values. If your accuracy requirements permit it, create an integer grid. It uses less disk space, and processing tends to be faster.

Float – creates a grid with floating point cell values. Floating point grids preserve coordinate accuracy at the expense of disk storage space.


Header format and description

<NCOLS xxx>
<NROWS xxx>
<XLLCENTER xxx | XLLCORNER xxx>
<YLLCENTER xxx | YLLCORNER xxx>
<CELLSIZE xxx>
{NODATA_VALUE xxx}
ROW 1
ROW 2
.
.
.
ROW n

where:

NCOLS is the number of columns in the ASCII file.

NROWS is the number of rows in the ASCII file.

XLLCENTER | XLLCORNER is either the x coordinate for the center or lower left corner of the lower left most cell in the grid.

YLLCENTER | YLLCORNER is either the x coordinate for the center or lower left corner of the lower left most cell in the grid.

CELLSIZE is the length of a cell’s edge.

NODATA_VALUE is the value in the ASCII file representing unknown values. It is optional, and defaults to -9999 if not specified.

xxx are numbers, and the cell values are space delimited.


Buffer

Creates a new coverage of buffer polygons around specified Input coverage features. Features can be polygons, lines, points or nodes.

The width of the buffer can be specified in one of three ways:

Fixed distance – specify a constant Distance to apply to all input features;

From item – choose the name of a numeric Distance item from the specified feature attribute table. The item value is the buffer distance for its associated feature;

From distance table – choose the name of a Distance item common to both the Input coverage and a Distance table that contains a numeric item named DIST. Every feature with a common Distance item value will be buffered by the associated DIST value.  See Using lookup tables for more information.

An item named INSIDE in the output polygon attribute table (PAT) identifies the buffer polygons. Polygons representing buffer zones have a value 100; outside polygons have the value 1. Overlapping polygons with a common INSIDE value are merged.

Notes

The Distance table must be sorted on the Distance item in ascending order.

A feature can be excluded from buffering by assigning it a value of 0 in the Distance item or in the DIST item in the Distance table.

To access the Line buffer styles, the Input coverage must be Built as LINE and NODE.

Use caution with Left and Right options of Line buffer style

Polygons can be reduced in size by specifying a negative buffer distance.

Buffer can create troublesome sliver polygons coded as non-buffer areas inside the buffer polygons. Remove them with the Eliminate tool.

How the default fuzzy tolerance is calculated

Examples

Related Topics


Example 1

Buffer of a line coverage using a Distance of 200 and Line buffer style of Flat Full.

Example 2

Buffer of a line coverage with Line buffer style of Flat Full and the following Distance table:

ROAD.LUT
CLASS   DIST
10      100.00
20      200.00
30      300.00


 A sliver polygon is a small areal feature commonly occurring along the borders of polygons following a topological overlay operation where the polygon boundaries do not match exactly. Buffering can also produce sliver polygons.


The coverage with features you want to buffer.


Choose the feature class you want to buffer:

Line – arcs

Poly – polygons

Point – points

Node – nodes


Choose the method you will use to buffer:

Fixed distance – specify one Distance for all buffer zones.

From item – choose the name of a numeric Distance item from the specified feature attribute table. The item value is the buffer distance for its associated feature.

From distance table – choose the name of a Distance item common to both the Input coverage and a Distance table that contains a numeric item named DIST. Every feature with a common Distance item value will be buffered by the associated DIST value. See Using lookup tables for more information.

Note that the table must be sorted on the Distance item in ascending order.


Specify one width for all buffer zones.


Lists items in the table of the specified Feature class.

When From item is selected, it lists only numeric items. Choose one to use as the buffer distance.

When From distance table is selected, it lists all items. Choose the item that is the relate item to the Distance table.


Shows the item values or the item definitions of the specified feature attribute table.


A lookup table that has at least the following items:

Buffer item – as the relate item to the Input coverage, it must be defined exactly like Distance item.

DIST – a numeric item that contains the buffer distance for each buffer item.


Choose a buffer style.  All options are available if the Input coverage is built as LINE and NODE; otherwise only Round Full is available.

Round Full – rounded end, buffer both sides.

Round Left – rounded end, buffer only the left side.

Round Right – rounded end, buffer only the right side.

Flat Full – straight end, buffer both sides.

Flat Left – straight end, buffer only the left side.

Flat Right – straight end, buffer only the right side.


The coverage you will create.


Buffer Regions

Creates region features by buffering Input coverage points, arcs, nodes, polygons or regions. The buffer regions may either be in a new Output coverage, or in a new or existing subclass in the Input coverage. New regions are appended to an existing subclass.

Since regions require supporting polygon topology, polygons will be created when the input Feature class is Point or Line; regions are then constructed from the polygons. If the regions are created in the Input coverage, the line data will become part of a network feature class, and points will become polygon labels.

WARNING: If you wish to maintain your point coverage, specify a new Output coverage.

WARNING: If you wish to maintain your line coverage, specify a new Output coverage. Otherwise, lines will become parts of polygons, and duplicate and coincident line data may be lost.

The width of the buffer can be specified in one of three ways:

Fixed distance – specify a constant Distance to apply to all input features;

From item – choose the name of a numeric Distance item from the specified feature attribute table. The item value is the buffer distance for its associated feature;

From distance table – choose the name of a Distance item common to both the Input coverage and a Distance table that contains a numeric item named DIST. Every feature with a common Distance item value will be buffered by the associated DIST value. See Using lookup tables for more information.

The specified Region items of the input feature attribute table (FAT) become output items in the output region subclass PAT. The specified items are used to group the feature attribute records in the input FAT on equal item values. All features in a group are buffered, and the generated buffer becomes a region. Since all specified item values for a group are the same for each item, these values are also assigned to the output region. If none are specified, each selected input feature will be buffered and converted into a buffer region. The number of output regions equals the number of input FAT record groups.

Notes

When the Output coverage is equal to the Input coverage, data in existing feature attribute tables is maintained, including sections, routes and regions, except for lines and points.

When the Output coverage is not equal to the Input coverage, the Output coverage may not already exist. Only generated regions and supporting arcs, nodes and polygons are written to the Output coverage. The AAT, polygon PAT or NAT are not transferred. PRJ, TIC and TOL files are copied.

A feature will not be buffered if its Buffer distance is zero. If you do not want to buffer a feature in the Input coverage, give it a buffer distance value of 0 in Distance item or DIST in Distance table.

Negative and positive distances can be used for buffer distances with the Poly and Region.<subclass> options. It is possible to shrink some polygons or regions and grow others in the same coverage when the Distance item or DIST in Distance table contains both positive and negative numbers.

The user may specify a buffer Fuzzy tolerance. The specified Buffer distance is checked against a minimum buffer tolerance which increases with the buffer distance. If the specified tolerance is less than the calculated tolerance, the required minimum is used.

To access the Line buffer styles, the Input coverage must be Built as LINE and NODE.

Use caution with Left and Right options of Line buffer style

Unlike the Buffer tool, where generated polygons may be either inside or outside the specified buffer zone, Buffer Regions does not fill holes in the generated buffer with polygons. Thus, there is no need for an INSIDE item, as with Buffer. Each generated region represents a true buffer or group of input features. The buffer regions may have “holes,” and other overlapping regions or polygons may “show through.”

Examples

In each of the examples below, the Buffer Regions results are compared to the standard Buffer tool results. Note that Region items are used to determine which features will create which regions when buffered. Regions may be discontiguous and/or overlapping.

Point coverage

Line coverage

Polygon coverage

Related Topics


Line buffer style

The Left and Right options use the topological left and right of the line, so line topology must be present for the use of any of these options.

Caution must be exercised in interpreting the “left” or “right” of a line. A single line segment defines two half planes, cutting a rectangular buffer into two clearly defined left and right sections. When connecting line segments, points that are on the left side of one segment may be on the right side of another connecting segment.

This ambiguity can be prevented by the concept of “not crossing over the line.” When buffer distances are small compared to arc lengths, the Buffer Regions tool will generate buffers that observe this principle for individual lines. However, lines may be connected into networks where more than two lines may come together, and in such instances, points may be on the left side of one line as well as on the right side of another. When buffer distances increase with respect to relative line lengths, the number of crossovers will increase.


Point coverage

This example shows a point coverage ‘pointcov’ buffered to create a region coverage ‘pointbuff’ with a subclass ‘sub’. The Region item POINTCOV-ID specifies that each point will be converted to a region.


Line coverage

This example shows a line coverage ‘linecov’ buffered to create a region coverage ‘linebuff’ with a subclass ‘sub’. The Line buffer style is Round Full. The Region item LINECOV-ID specifies that each line will be converted to a region.


Polygon coverage

This example shows a polygon coverage ‘polycov’ buffered to create a region coverage ‘polybuff’ with a subclass ‘sub’. The Region item POLYCOV-ID specifies that each polygon will be converted to a region. The Distance table is POLYCOV.LUT and the Distance item is BUFFDIST. Note that negative distances may be specified to buffer the inside of a polygon feature.

Listing of POLYCOV.LUT:

BUFFDIST   DIST
   1         50
   2        -10


The coverage containing features you want to buffer.


The coverage you will create.


The feature classes available for buffering. This list includes one or several of the following:

Line – arcs

Poly – polygons

Point – points

Node – nodes

Region.<subclass> – buffers regions of the specified subclass


Choose the method you will use to buffer.

Fixed distance – specify one Distance for all buffer zones.

From item – choose the name of a numeric Distance item from the specified feature attribute table. The item value is the buffer distance for its associated feature.

From distance table – choose the name of a Distance item common to both the Input coverage and a Distance table that contains a numeric item named DIST. Every feature with a common Distance item value will be buffered by the associated DIST value. See Using lookup tables for more information.


The region subclass you want to create.

NOTE: If it already exists, the new data will be appended to it.


Choose the item from the specified feature attribute table whose values you want to use as the feature’s buffer distance. If a Distance table is used, the Distance item functions as a lookup item in the distance table.

This option lets you define multiple buffer sizes for the buffer zones for the selected feature class.


Shows the item values or the item definitions of the specified feature attribute table.


A lookup table that lists a buffer distance for each distance item. The table must already exist and have the following items:

Distance item – it must be defined exactly like the specified Distance item from the selected feature class.

DIST – the width of the buffer you want to create for each buffer item value. Its data type must be numeric. For polygon and region feature classes, if DIST contains a negative value, a buffer will be generated on the inside of the polygon or region feature.


The width of the buffer zones you want to create.

This option lets you define a single buffer size for all buffer zones for the specified Feature class. Buffer zones are individual regions.


The minimum distance within which coordinates, arcs and intersections are merged into one. The value displayed here is read from your Input coverage and will be applied to the coverage you will create. Its unit of measure is that of the Input coverage.


Choose the type of buffer regions you want to create:

Noncontiguous – creates contiguous as well as noncontiguous regions in the Output coverage.

Contiguous – creates only contiguous regions in the Output coverage.


Lists attribute items for your specified Feature class. Choose the items you want to transfer to the buffer regions in the Output coverage. Attribute value combinations for the selected items will be unique for each generated buffer region.


Choose a buffer style.  All options are available if the Input coverage is built as LINE and NODE; otherwise only Round Full is available.

Round Full – rounded end, buffer both sides.

Round Left – rounded end, buffer only the left side.

Round Right – rounded end, buffer only the right side.

Flat Full – straight end, buffer both sides.

Flat Left – straight end, buffer only the left side.

Flat Right – straight end, buffer only the right side.


Choose which items to view.

Unchecked – displays all items.

Checked – displays only the items selected for transfer to the output buffer regions.


Buffer Wizard

Creates buffer polygons or regions around specified input coverage features. Input features can be polygons, lines, points, or nodes, or regions. The output coverage can be either a polygon coverage or a region coverage.

The Buffer Wizard provides functionality that the other buffer tools (Buffer, Buffer Regions) do not:

Performing multiple polygon buffers at once. The wizard will BUFFER up to five coverages, then UNION all the buffered coverages into a single coverage.

Performing multiple region buffers at once. The wizard will buffer up to five coverages with the REGIONBUFFER command. NOTE: The output coverage must be the same as the input coverage.

Changing the name of the INSIDE item and values. The Buffer tool always creates an item named INSIDE, with values of 100 representing buffer zones, and values of 1 representing non-buffer zones. With the wizard, you can change the item name and values to suit your needs.

Notes

To access the Line buffer styles, the Input coverage must be Built as LINE and NODE.

When the output is a polygon coverage, the wizard is like the Buffer tool as it runs the BUFFER command.

When the output is a region coverage, the wizard is like the Buffer Regions tool as it runs the REGIONBUFFER command.

Related Topics


Build

Creates or updates feature attribute tables and polygon topology. Build is also used to synchronize polygon User-IDs with label point User-IDs.

The tool determines the Feature classes in the Input coverage and lists those available for building:

Build polygons

Build lines

Build points

Build nodes

Build annotation.subclass

Recommended post-processing

Build deletes item indexes. To create an item index, access the item from ArcCatalog.

Notes

Build and Clean are alike in that they both define topology. But Clean uses a fuzzy tolerance and can therefore detect and resolve intersections. Build does not adjust any coordinates.

Build should not be executed on a coverage if it contains coordinate errors. Errors which could cause problems for Build with the Poly option include intersecting arcs (where no node is defined at the intersection), unclosed polygons or unmatched nodes and polygon slivers.

User-defined items in existing feature attribute tables are always maintained.

Edit masks are removed for all feature classes except Anno.<subclass>.

Build does not maintain link features.

Related Topics


Build Polygons:

Polygon topology and a polygon attribute table (PAT) are created or updated. One additional polygon, the universe polygon, is also created.

Polygon topology is created by identifying the set of arcs which define each polygon and the internal numbers of polygons which are to the left and right sides of each arc. From-nodes and to-nodes are used to determine the left/right orientation for each arc.

A polygon’s label point User-ID is assigned to the polygon User-ID. Polygons without a label point have a User-ID value of 0. If a polygon has more than one label point, one is chosen arbitrarily and is assigned to the polygon User-ID.

Label points are needed to retain a polygon’s attributes. Although not required, it is recommended that label points have unique IDs.

Do not use the Poly option on a point coverage; user-defined point attributes can be lost.

Arc-node topology and an arc attribute table (AAT) are created or updated.

If a node attribute tables (NAT) exists, it is updated.

To ensure that coincident nodes with different z-values, as for an overpass/underpass in a transportation network, are not eliminated, use Renumber Nodes and specify the From- and To-node-elevation.

A route-system and its RAT and SEC tables are maintained and updated. The SEC is updated with correct ARCLINK# values.

Build cannot be executed on a region coverage that contains unclosed regions.

Adds topology to preliminary regions by creating a .PAT and .PATsubclass. The region subclass must already exist.


Build Lines:

An arc attribute table (AAT) is created or updated.

Build with the Line option does not rebuild arc-node topology as does Build with Poly and the Clean tool. You can use the Renumber Nodes tool to update the internal node numbers of each arc and the internal numbers of the From-nodes and To-nodes. You can do this before or after Build.

When creating regions from a line coverage, each arc must form a closed loop which defines a region. Use Build with Line before running the Line Coverage to Region tool.


Build Points:

A point attribute table (PAT) is created or updated and the AREA and PERIMETER values are set to 0.

Do not use the Point option on a polygon coverage; user-defined polygon attributes can be lost.


Build Nodes:

A node attribute table (NAT) is created or updated.

Build renumbers nodes whenever the NAT is updated, but unlike the Renumber Nodes tool, it preserves all coincident nodes instead of dissolving them. Nodes are automatically renumbered, starting with 1, to ensure continuous node numbers.

Building a line coverage with the Node option assigns an internal FNODE# and TNODE# to each node.


Build Anno.<subclasses>:

A text attribute table (TAT) is created. The TAT is used to store attributes and set up relates to other feature classes.

Build never updates a TAT. To update or add information to the TAT, use the ADDTEXT command.

All spatial indices are maintained.


The coverage whose feature attribute tables you want to create or update.


Choose the feature class you want to build.

Poly – creates or updates polygon and arc-node topology and the related PAT, AAT, and NAT.

Line – creates or updates the AAT.

Point – creates or updates the PAT for label points.

Node – creates or updates the NAT.

Anno.<subclass> – creates the TAT. NOTE: This table never needs to be rebuilt.


Edit masks are rectangular areas defining the spatial extent of edits made on features in a coverage. The coordinates for these areas are stored in the MSK file. The Build and Clean tools remove this file.


The universe polygon encompasses the area outside the bounding box of a coverage. It is always the first record in a PAT, its AREA equals the negative sum of all the polygons in the coverage, and its User-ID value is always 0 because it has no label point.


No help available (Arc Toolbox 9999999)


Build Geometric Network Wizard

This wizard will help you build a geometric network. Geometric networks allow you to model the behavior of utility networks such as electrical or water networks. A geometric network can be built in either a Personal Geodatabase or an SDE Geodatabase. It is composed of features from one or more feature classes in a feature dataset, and stores the connectivity between those features.

This wizard does not support remote processing using a Geoprocessing Server.


How would you like to build your geometric network?

You can build a geometric network from existing feature classes in this feature dataset, or you can build an empty geometric network.  If there are no feature classes in this feature dataset, the option to build a geometric network from existing feature classes is disabled.

An existing feature class can be used to build a geometric network if it meets the following criteria:

•	The feature class must have a shape field of type Point or Line

•	The feature class must be a simple feature class (e.g., not an annotation or dimension feature class)

•	The feature class must not be part of another existing geometric network

•	The feature class must not be registered as versioned

•	If the feature class has a field called ‘Enabled’:

•	The ‘Enabled’ field must be either of type Short Integer or Long Integer

•	The ‘Enabled’ field must not have a specified Domain, unless it is the EnabledDomain created by a previous geometric network

If there are feature classes in this feature dataset but none of which meet the above conditions, you will get an error message listing these feature classes and the reason why each cannot be made part of the new geometric network.


Choose a name for your network

Enter a name for your new geometric network in the box provided. If the name you propose is invalid, you will need to give the network a different name.  Below is the list of the most common reasons for a name being invalid:

There exists another geometric network in the geodatabase with the proposed name

0	There are invalid characters in the proposed name


Choose your feature classes

In order to build a geometric network from a feature class, the feature class must meet the following criteria:

•	The feature class must have a shape field of type Point or Line

•	The feature class must be a simple feature class (e.g., not an annotation or dimension feature class)

•	The feature class must not be part of another existing geometric network

•	The feature class must not be registered as versioned

•	If the feature class has a field called ‘Enabled’:

•	The ‘Enabled’ field must be either of type Short Integer or Long Integer

•	The ‘Enabled’ field must not have a specified Domain, unless it is the EnabledDomain created by a previous geometric network

The feature classes in this feature dataset that meet the above criteria are listed in the checklist.  Check the feature classes from which you want to build a geometric network.

0	If there are feature classes in this feature dataset that do not meet one or more of the above conditions, the Show Unavailable Feature Classes button will be enabled.  Click this button to view a list of these feature classes and the reason why each cannot be made part of the new geometric network.

1	The feature classes you choose to build a new geometric network with must have an Integer field named ‘Enabled’.  If a feature class does not have this field, then the field is automatically added to the feature class with its value for each feature set to ‘True’.

Choose a name for your network

Enter a name for your new geometric network in the box provided. If the name you propose is invalid, you will need to give the network a different name.  Below is the list of the most common reasons for a name being invalid:

There exists another geometric network in the geodatabase with the proposed name

0	There are invalid characters in the proposed name


Do you want complex edges in your network?

A complex edge allows an edge feature to correspond with more than one network element in the logical network. For example, in a water distribution network, a water main will be represented as a complex edge, whereas a service off that water main remains a simple edge. A complex edge can be thought of as a composite feature capable of supporting many network elements.

0	Choose one of the following options:

 No –	The new geometric network will contain only simple edges.

0	Yes – The edges in the feature classes that are checked will become complex edges in the new geometric network.

The feature classes listed are the linear feature classes that you selected earlier in this wizard.


Do your features need to be snapped?

Snapping allows the wizard to make slight modifications to your data to correct for potential connectivity. If you know that your data already has exact geometry, answer “No” on this panel.

0	Choose one of the following options:

No - The wizard assumes that the feature classes have exact geometry. This means that connectivity between features in the network will only be created if the junctions or line-ends are exactly coincident. An example of data that has exact geometry is one that has been integrated using the Editor toolbar in ArcMap. For more information on data integration, see “Editing topological features” in Editing in ArcMap.

0	Yes - For each junction or line-end in a moveable feature class, the wizard will search for other nearby junctions or line-ends to which to snap. If another junction or line-end is encountered, then the wizard will move these junctions or line-ends to coincide.

The snap tolerance controls the search distance used for establishing connectivity during the network building process.  The snap tolerance is specified in map units.  The wizard provides you with a minimum snap tolerance derived from the spatial reference of the feature dataset.  You can increase the tolerance to a higher value to reflect the actual precision of your feature data.

0	The list at the bottom of the panel contains the feature classes you specified earlier to participate in the new geometric network. Specify the moveable feature classes by checking the feature classes in the list whose features can be moved to correct for connectivity. Only the features in the specified moveable feature classes will be moved.


Does your network have sources or sinks?

Sources and sinks drive flow through a utility network. Sources are junction features that push flow away from themselves through the edges of the network. For example, in a water distribution network, pump stations can be modeled as sources, since they drive the water through the pipes away from the pump stations. Sinks are junction features that pull flow toward themselves from the edges in the network. For example, in a river network, the mouth of the river can be modeled as a sink, since gravity drives all water towards it. Flow moves away from sources or towards sinks. The geometric network uses sources and sinks to determine the direction of flow along its edges.

0	Choose one of the following options:

No - No sources and sinks are created in your new geometric network.

0	Yes - Sources and sinks are created from the selected feature classes in your geometric network.

The feature classes listed are the point feature classes you chose from which to build a geometric network.  Check the feature classes from which you want to create sources and sinks.

0	If a point feature class is not listed, it is due to one or more of the following:

•	The feature class has a field called ‘AncillaryRole’ that is not of type Short Integer or Long Integer

•	The feature class has a field called ‘AncillaryRole’ whose domain is not the AncillaryRoleDomain created by a previous geometric network

Click Show Unavailable Feature Classes to view the point feature classes that have the above conditions.  If the Show Unavailable Feature Classes button is disabled, then there are no point feature classes that have the above conditions.

The feature classes you choose from which to create sources and sinks must have an Integer field named ‘AncillaryRole’.  If a feature class does not have this field, then the field is automatically added to the feature class with its value for each feature set to ‘None’.

If you choose a feature class with an existing AncillaryRole field, but its AncillaryRole field contains values outside the AncillaryRoleDomain (0, 1, and 2), those values outside this domain will be overwritten with the value 0.

NOTE: After building your new geometric network, flow direction on the network will be uninitialized, even though it has sources and sinks.  You will need to set flow direction in an ArcMap edit session.


Do you want to assign weights to your network?

Certain network features can have weights associated with them to further refine the network analysis performed by trace tasks. There are two main types of weights: cost weights and classification weights.

An example of a cost weight in a utility network is the length of a pipe. Cost weights are used by certain trace tasks that return a cost value. For example, the Find Path trace task finds a path that minimizes the cost specified in a weight.

Classification weights are used to restrict tracing on specific features based on a certain attribute value. Examples of classification weights in a utility network include the “Phase” attribute in circuits, the pipe diameter in a water network, and road classification in a street network.

Bitgate weights are a special kind of classification weight. It allows multiple attributes to be specified in a single value. An example of a bitgate weight in a street network is the following PermittedVehicles attribute:

PermittedVehicles specifies which types of vehicles are permitted on a road: first bit (value 1) = Pedestrians, second bit (value 2) = Bicycles, third bit (value 4) = Automobiles, fourth bit (value 8) = Trucks. This attribute has sixteen possible values. For example, a road that has a PermittedVehicles value of 6 (equal to 2+4) would allow bicycles (value 2) and automobiles (value 4) but not pedestrians or trucks.

Bitgate weights also must have a size. The size of the bitgate weight for the above example is 4, since it is tracking four possible vehicles – pedestrians, bicycles, automobiles, and trucks. The maximum bitgate size is 31.

For more information on weights, please see the ArcGIS Network Model technical document.

Weights must be created when the geometric network is created. In order to add a weight, the geometric network must be deleted and rebuilt.

Choose one of the following options:

No - No weights are created in your network.

Yes - Weights are created in your network.

The type of the weight determines which feature attributes can be associated to the weight. Integer weights can be associated with feature attributes of type Short Integer or Long Integer; Single weights can be associated with feature attributes of type Float; Double weights can be associated with feature attributes of type Float or Double; and Bitgate weights can be associated with feature attributes of type Short Integer or Long Integer.

To create a weight, simply specify a weight name and the type of this weight. If the weight is of type Bitgate, then a bitgate size must be specified. If you would like to create more than one weight, click the New button and an additional line is added to the table.


Assign your weights to fields in your feature classes

The weights you have specified on the previous panel are listed in the dropdown list at the top of this panel. Click on this dropdown list to select a weight.

Click in the ‘Associated field’ column next to a feature class to which you wish to associate this weight. Listed in the dropdown list in the ‘Associated field’ column are the possible attribute fields of the feature class with which the weight can be associated. For example, if the weight selected is of type Integer, the dropdown list in the ‘Associated field’ column will contain attribute fields that are of type Short Integer or Long Integer. Click the attribute field you wish to associate to this weight. If you do not want to associate any field from this feature class to this weight, click <None>. Repeat for all feature classes that you want to associate to this weight.

Repeat the above procedure for all the specified weights.


Do you need to specify a configuration keyword?


Summary of your input

This is a listing of the parameters you specified in the wizard for building a geometric network. If any parameters are incorrect, click Back to go back and make changes. Otherwise, click Finish to begin building your new geometric network.


Do you want to preserve existing enabled values?

This panel is presented when one or more of the feature classes specified to be used to create a new geometric network already has an attribute field called ‘Enabled’.

Choose one of the following options:

No - Current values in the existing ‘Enabled’ fields are disregarded and are overwritten by values of ‘True’. The network will be built with all network elements initially enabled.

Yes - Valid values in the existing ‘Enabled’ fields are preserved. Values in the ‘Enabled’ field are valid if they have a value of either 0 (False) or 1 (True). Other values are invalid and will be overwritten with the value 1 (True). After the network is built, each network element will be either enabled or disabled, based on the value in the ‘Enabled’ field.


CAD to Geodatabase

Converts a feature class stored in a CAD file to a new feature class in a Geodatabase and assigns it the ESRI Simple Feature behavior class.

When you import CAD features, you create a new standalone feature class, a new feature dataset and feature class, or a feature class in an existing feature dataset. In the first two cases, you have to define a spatial reference.

If your CAD dataset has a defined projection, the tool will automatically create the new feature class with the same projection, unless you specify otherwise. If you do choose to import the data into a different projection than the source data is in, the features will automatically be projected.

Because all feature classes in a feature dataset share the same spatial reference, you must only specify a new spatial reference when loading the first feature class or when creating the feature dataset in ArcCatalog.

A suggested grid size is given based on the spatial reference, average feature size, and number of features in the input coverage. The suggested grid size is only an approximation. You can determine the optimum grid size for any feature class by examining the data and the needs of the application querying it.

When you convert data from one format to another, a question arises about how data of a specific type maps from one format to the other. Importing data into the geodatabase is no exception. In this case, how both the spatial type and the attribute field type map from one data type to another must be considered. For each geodatabase field type, the field itself is persistently stored in the database differently depending on which RDBMS stores the geodatabase. All feature class types and attribute item types in CAD feature classes are mapped to geometry and field types in the geodatabase.

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings…. You may also choose to not include certain columns from the input table in the new Geodatabase table.

Notes

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the Geodatabase you specify and whether you are using SDE or Access.

For more details on the mapping of feature class type to geodatabase geometry type between CAD datasets and the geodatabase click here

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped until a valid name is produced.

Spatial Reference and Domain extents

Spatial index grid

Related Topics


The name of the CAD dataset to be converted to a Geodatabase feature class.


The CAD feature class you want to convert.


The name of the Geodatabase that will contain the dataset with the new feature class.


The name of a new or existing dataset that will contain the new feature class in the specified Geodatabase.


The name of the feature class to be created.

The feature class name cannot begin with a numeric character.


The settings that will be used during the conversion. Click the Change Settings… button to modify them.

Spatial reference: The output coordinate system determined from the input coverage feature class. The projection will be copied from the coverage, and the spatial domain calculated.

Grid size: The spatial index grid is a two-dimensional grid system that spans a layer, like the locator grid you might find on a common road map. It is used to quickly locate features in a dataset that might match the criteria of a spatial search.

Item names: Shows whether input item names have been modified or deleted. INFO files allow characters in column names that other databases do not. The tool finds any illegal characters or reserved word field names in the input table, and corrects them for the output table.

Query: A SQL where clause that is used to create a selected set. Only the selected set will be converted to a feature class. If no expression is given, all features will be converted.

Keyword: A keyword that references database storage parameters on an SDE server. When loading data into an SDE Geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Geometry: M and Z values must be created at the same time as a feature class or feature dataset is created, as they can not be subsequently added. If the Enable M values on the output is checked the output feature class will have linear measurement (M) values. If you do not want your new feature class and/or feature dataset to contain M values, uncheck this option.


Click to modify the Output settings.


CAD feature class to geodatabase geometry type mapping

CAD feature class	Geodatabase geometry

point	point

polygon	line (polyline)

polyline	polygon


Calculate COGO Attributes

Calculates coordinate geometry (COGO) attribute values for two-point lines and curves. All circular curve entities—identified by a Curve item value of 1—are converted into COGO curves by calculating the curve attributes required by COGO. A Curve item value of 0 identifies an arc as a non-curve, such as a two-point line, spiral, ellipse or poly-line.

Calculate COGO Attributes supports five Reference systems for direction attribute calculation and storage:

Bearing – uses bearings in all four quadrants when calculating and storing the direction attributes. Use this option if your source data is referenced in bearing or you do not know your source data’s reference system. This is the default option.

North Bearing – uses only bearings in the northeast and northwest quadrants when calculating and storing the direction attributes. Use this option if your source data is referenced in north bearing.

Azimuth – uses azimuths measured clockwise from the north when calculating and storing the direction attributes. Use this option if your source data is referenced in azimuth.

South Azimuth – uses south azimuths measured clockwise from the south when calculating and storing the direction attributes. Use this option if your source data is referenced in south azimuth.

Polar – uses polar angles measured counterclockwise starting at the positive x-axis when calculating and storing the direction attributes. Use this option if your source data is referenced in polar.

Required post-processing

Run the Renumber Nodes tool and then the Build tool to preserve topology. Node attributes are not preserved.

Notes

If the Input coverage does not have COGO attributes, the tool appends them to its AAT and calculates and stores their values. If the Input coverage has COGO attributes, then those attributes will be destroyed and recalculated.

The Rotation angle and Scale factor allow you to rotate a grid’s calculated COGO attributes and scale them to the ground (grid-to-ground conversion) before they are stored as values in the COGO items. The Rotation angle affects the ANGLE item. The Scale factor affects the items DISTANCE, RADIUS, TANGENT, and ARCLENGTH.

A circular curve with less than three points is converted to a two-point line and flagged with an asterisk (‘*’) in the SIDE item of the AAT.

Converting a line coverage—created with the Coverage to IGES tool or the DXF to Coverage Wizard and the IGDS to Coverage Wizard—to a COGO coverage splits graphic entities such as spirals, ellipses, and poly-lines into many two-point lines with calculated directions and distances. Use the Join Tables tool to append the Curve item from the <output coverage>.ACODE file of any of these tools to the COGO coverage AAT.

How to identify a circular curve requires the ArcEdit module.

The tool does not maintain route or region subclasses. To preserve region or route subclasses, use the ARC command COGOINVERSE.

Related Topics


The coverage whose COGO attribute data you want to calculate.


The coverage you will create with the calculated COGO attribute data.


The item in the Input coverage AAT that indicates whether an arc is a curve or not.

A Curve item value of 1 identifies an arc as a circular curve, a value of 0 identifies an arc as a two-point line, or a spiral, an ellipse, poly-line or anything else.


Choose the Reference system you want to use when calculating and storing the direction attributes:

Bearing – uses bearings in all four quadrants. Use this option if your source data is referenced in bearing or you do not know your source data’s reference system. This is the default.

North Bearing – uses only bearings in the northeast and northwest quadrants. Use this option if your source data is referenced in north bearing.

Azimuth – uses azimuths measured clockwise from the north. Use this option if your source data is referenced in azimuth.

South Azimuth – uses south azimuths measured clockwise starting south when calculating and storing the direction attributes. Use this option if your source data is referenced in south azimuth.

Polar – uses polar angles measured counterclockwise starting at the positive x-axis. Use this option if your source data is referenced in polar.


Choose the units of direction measurement you want to use in the distance attribute calculation and storage:

Degrees Minutes Seconds – Degrees, minutes, seconds. This is the default.

Decimal degrees – Decimal degrees (units of 10).

Grads – Grads.

Grads, Centigrads, Centicentigrads – Grads, centigrads (units of 1/100) , and centicentigrads (units of 1/10 000).


The number of Decimal places used when calculating and storing the DISTANCE attribute value. The range of valid decimal places is from 0 to 10.


The Rotation angle is used to adjust cardinal direction differences between a local coordinate system and a ground coordinate system such as State Plane. Calculated COGO attributes are rotated from their local coordinate system location to the ground coordinate system location. The Rotation angle value is stored in the ANGLE item. The default value 0 means that no grid-to-ground rotation is performed. The value can be positive or negative.


The Scale factor scales calculated COGO attributes from a local coordinate system to a ground coordinate system such as State Plane. The scaling affects the DISTANCE, RADIUS, TANGENT, and ARCLENGTH items. The default value 1 means that no Scale factor is applied.


How to identify a circular curve for the Calculate COGO attributes tool
How to identify a circular curve

NOTE: You must have the ArcEdit module to complete this task.

Steps to identify a circular curve and update its Curve item value in the AAT:

1 Start ArcEdit

2 Identify all circular curves and update their CURVEITEM (possible alternate spellings: CRVITEM, C-ITEM, CVITEM) value to 1.

3 Input the COGO coverage into the Calculate COGO attributes tool.


Calculate Legal Area

Computes the legal area, legal perimeter, and closure error for parcels, using COGO attributes, and writes them to the polygon attribute table (PAT). Upon selecting the Input coverage, the tool verifies that the arc attribute table (AAT) contains the required COGO attributes.

Depending on your Calculate selection, one or all of these items are appended to the polygon attribute table (PAT):

ITEM NAME      WIDTH  OUTPUT  TYPE  N.DEC
LOT-AREA           8     18     F       5
LOT-PERIMETER      8     18     F       5
LOT-CLOSURE        4      5     B       -

The tool supports three coordinate Adjustment methods for a parcel’s area, perimeter, and closure:

Compass – adjusts the lot closure using the Compass rule.
Use this option to adjust directions and distances equally.

Transit – adjusts the lot closure using the Transit rule.
Use this option to adjust distances more than directions.

Crandall – adjusts the lot closure using the Crandall rule.
Use this option to adjust only distances.

Notes

The Input coverage must be a clean polygon coverage with both an AAT file and a PAT. The coverage cannot contain any arc intersections or coincident (duplicate) arcs. The polygons for which you want values calculated cannot contain any polygon islands or dangling arcs.

How items are calculated.

If LOT-AREA cannot be calculated for any given polygon, its value will be recorded as 0.

LOT-CLOSURE can be used to validate each lot area calculation; that is, whether a lot is properly defined and closed. The value of LOT-AREA represents the reciprocal of the relative error. This means that the higher the value, the better the closure. Values can range from 1 to 99999 with the highest value representing a ‘perfect’ closure. For example, a value of 57000 would represent a 1-unit closure error every 57000 units for the traverse of a particular polygon. If the lot area could not be calculated for any given polygon, the error will be recorded as 0.

The tool can be run on the same coverage more than once. If any changes have been made to the Input coverage since it was last built, it must be rebuilt. Each time the command is issued, the existing item values will be replaced with recalculated values.

If you get the following message, it means that the named polygon contains an island polygon or a bow tie. You should check your data to make sure everything is correct.

"Compound polygon encountered, polygon 4"

Related Topics


The polygon coverage whose legal area, legal perimeter, or lot closure error you want to calculate. The coverage must have an AAT with COGO attributes.


Choose what you want to calculate.

All – all values are calculated.

Area – calculates the legal area into the LOT-AREA item.

Perimeter – calculates the legal perimeter into the LOT-PERIMETER item.

Closure – calculates the lot closure error into the LOT-CLOSURE item. This value is recorded as the reciprocal of the relative error.


Choose the type of traverse Adjustment to apply to each parcel:

Compass – adjusts the lot closure using the Compass rule. Use this option to adjust directions and distances equally.

Transit – adjusts the lot closure using the Transit rule. Use this option to adjust distances more than directions.

Crandall – adjusts the lot closure using the Crandall rule. Use this option to adjust only distances.


Required COGO attributes

The AAT must contain these COGO attributes in order to calculate the legal area, legal perimeter, and closure error:

ITEM NAME   WIDTH   OUTPUT   TYPE
ANGLE          10      10      C
DISTANCE        8       8      C
RADIUS          8       8      C
DELTA          10      10      C
TANGENT         8       8      C
ARCLENGTH       8       8      C
SIDE            1       1      C

ANGLE - the direction of two-point lines or the chord direction of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves.

DISTANCE - the length of two-point lines or the chord length of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves.

RADIUS - the circular curve radius or the first radius of a spiral. This item is needed when working with circular curves and spiral curves.

DELTA is the delta angle of a circular curve or spiral. This item is needed when working with circular curves.

TANGENT - the tangent length of a circular curve or the first tangent length of a spiral.

ARCLENGTH - the arc length of a circular curve or spiral. This item is needed when working with circular curves and spiral curves.

SIDE - the right or left side where the radius point for curves or radius points for spirals are located with respect to the circular curve or spiral. This item is needed when working with circular curves and spiral curves.


The Compass rule, also known as Bowditch rule, is the most commonly used adjustment method. It does not distinguish between distances and direction, rather assumes that closure errors result equally from errors in observed directions and errors in measured distances. As a result, each direction and distance of every arc is adjusted to close. The adjustment for each direction and distance reflects the total closure error.


The Transit rule assumes that directions are measured with a higher degree of precision than distances. As a result, both direction and distances are adjusted, however direction bearings are given greater weight and are therefore adjusted less than distances.

Compared to the Compass rule, the Transit rule adjusts distances more and directions less.


The Crandall rule assumes that closure errors are caused by errors in measured distances. As a result, measured distances are adjusted for each arc and observed directions are preserved. The adjustment for each distance reflects the total closure  error.

Compared to the Compass rule, the Crandall rule adjusts distances more and directions not at all.


How items are calculated

The tool assembles a traverse for each polygon in the coverage, then calculates the area, perimeter and closure. This information is then stored in the coverage’s PAT file. The LOT-PERIMETER for each polygon is calculated as the sum of the DISTANCE attribute values for the arcs of the polygon, unless an arc is a curve, in which case, the ARCLENGTH attribute value is used instead of DISTANCE. The LOT-AREA is calculated for the traverse after it is adjusted to force closure. Areas enclosed by curves are added/subtracted so that the area calculated from the traverse is appropriate. The LOT-CLOSURE of the traverse is stored as the reciprocal of the relative error of the traverse.


The ArcToolbox Analysis Tools
The Analysis Tools

The analysis tools are a collection of geoprocessing toolsets. They work primarily on coverages, spatial features, and related attribute data.

Extract Toolset

These tools extract spatial features from a coverage or a set of coverages, based on attribute queries, and store them in a new coverage.

Overlay Toolset

These tools overlay two coverages to combine, erase, or update spatial features in a new coverage.

Proximity Toolset

These tools determine the proximity of spatial features within a coverage or between two coverages.

Statistics Toolset

These tools perform standard statistical analyses on attribute data.

Surface Toolset

These tools create and analyze 3D surfaces.


Extracting features with ArcToolbox
Extract Toolset

These tools extract spatial features from a coverage or a set of coverages, based on attribute queries, and store them in a new coverage.

Wizard

Extract Wizard

Guides users through feature selection and extraction operations. The wizard helps new users choose from several query and extraction options to create the desired results.

Tools

Clip

Uses the outside polygon boundary of a Clip coverage to cookie-cut features and attributes from an Input coverage.

Query Regions

Creates new regions based on the attribute values of input region or polygon layers and aggregates regions according to specified attribute items.

Select

Extracts selected features from an Input coverage and stores them in the Output coverage.

Split

Clips portions of the Input coverage into multiple coverages.


Overlaying features from two coverages with ArcToolbox
Overlay Toolset

These tools overlay two coverages to combine, erase, or update spatial features in a new coverage.

Wizard

Overlay Wizard

Performs any of the three standard overlay operations: Identity, Intersect, and Union.

Tools

Eliminate

Eliminates polygons or lines from a coverage by merging them with adjacent features, selected for deletion based on attribute query or by applying the criteria contained in a selection file.

Erase

Creates a new coverage by overlaying the polygons of the Erase coverage with the features of the Input coverage. Only those portions of the input coverage features falling outside the erase polygon outside boundaries are copied to the Output coverage.

Identity

Creates a new coverage by combining with the point, line or polygon features of one coverage with the polygons of the overlaid coverage. All features in the first coverage and only the overlapping features in the overlaid coverage are copied. Attributes from both coverages are copied to the output.

Intersect

Creates a new coverage by combining the point, line or polygon features of one coverage with the polygons of the overlaid coverage. Only the features of the first coverage that fall within the intersect polygons in the overlayed coverage are copied . Attributes from both coverages are copied to the output.

Union

Creates a new coverage by overlaying the polygons in the Union coverage with those in the Input coverage.

Update

Creates a new coverage by cookie-cutting the features and attributes from one coverage that fall within the outer boundary of the overlaid coverage. Attributes are updated and topology is rebuilt.


Determining proximity of features with ArcToolbox
Proximity Toolset

These tools determine the proximity of spatial features within a coverage or between two coverages.

Wizard

Buffer Wizard

Creates rings or bands, of fixed or varying width, around spatial features. The wizard helps new users choose from many buffer options to create the desired results. Output buffer zones are merged into polygons or maintained as separate regions.

Tools

Buffer

Creates a polygon coverage of buffers that surround point, node, line or polygon features. Overlapping buffer zones are merged.

Buffer Regions

Creates a region coverage of buffers that surround specified input coverage features. Overlapping buffer zones are maintained as separate regions.

Create Thiessen Polygons

Converts points to a coverage of Thiessen proximal polygons.

Near

Computes the distance from every Input coverage point to the nearest Near coverage point, line vertex, or node within the maximum Search radius.

Point Distance

Computes the point-to-point distance between each point in one coverage and all points in another coverage within the maximum Search radius.

Point Node

Transfers all point attributes from an input coverage to the closest nodes within a specified radius in the same or another coverage.


Analyzing attribute data with ArcToolbox
Statistics Toolset

These tools perform standard statistical analyses on attribute data.

Wizard

Statistics Wizard

Combines the functionality of the Frequency and Summary Statistics tools to perform frequency and summary, mean, minimum, maximum and standard deviation analyses on attribute data and saves the results in a new table.

Tools

Frequency

Creates a table of unique attribute values and how often each one occurs in the analyzed table.

Summary Statistics

Generates summary statistics for items in a table and saves them to a new table.


Creating and analyzing 3D surfaces with ArcToolbox
Surface Toolset

These tools create and analyze 3D surfaces.

Wizard

Contour Wizard

Converts a tin or grid to a coverage containing contours or isolines.

Tools

Cut & Fill

Summarizes the areas and volumes of change during a cut-and-fill operation.

Visibility

Analyzes visual exposure and performs viewshed analysis.

Volume

Calculates the area and volume of a tin.


ArcToolbox Conversion Tools
The Conversion Tools

The conversion tools work with common geodata formats, such as coverage, shapefile, grid, DEM, DLG, SDTS, TIGER, tin, attribute data, and ESRI’s new data formats.

Export Toolsets

A collection of toolsets that further organize tools that convert ESRI native data formats to common and frequently used geodata formats.

Export from CAD Toolset

These tools convert common Computer-aided Drafting (CAD) file formats to ESRI data formats.

Export from Coverage Toolset

These tools convert coverages to a variety of commonly used geodata formats, among them DLG, DXF, Geodatabase, IGDS, SDTS, TIGER, shapefile, and VPF.

Export from Geodatabase Toolset

These tools convert ESRI’s new data formats to other ESRI data formats.

Export from Raster Toolset

These tools convert grid data to other raster, vector, and ASCII formats.

Export from Shapefile Toolset

These tools convert shapefiles to common geodata formats, including ESRI’s new data formats.

Export from Table Toolset

These tools convert INFO tables to common database table formats, including ESRI’s new data formats.

Export from Tin Toolset

These tools convert tin data to other ESRI data formats as well as browser-viewable format.

Import Toolsets

A collection of toolsets that further organize tools that convert common and frequently used geodata formats to ESRI native data formats.

Import to Coverage Toolset

These tools convert a variety of frequently used geodata formats to coverages, among them DLG, DXF, Etak, IGDS, SDTS, TIGER, and shapefile.

Import to Geodatabase Toolset

These tools convert coverages, shapefiles and tables to ESRI’s new geodata formats.

Import to Raster Toolset

These tools convert vector, raster, and ASCII data to grid format.

Import to Shapefile Toolset

These tools convert common geodata formats, including the new ESRI data formats to shapefiles.

Import to Table Toolset

These tools convert attribute data in table formats (dBASE, DBMS, geodatabase and OLE), to INFO format.

Import to Tin Toolset

These tools convert coverage, grid, and interchange file data to tin format.


ArcToolbox Export From CAD Toolset
Export from CAD Toolset

These tools convert common Computer-aided Drafting (CAD) file formats to ESRI data formats.

Tools

CAD to Geodatabase

Converts common Computer-aided Drafting (CAD) file formats, among them DXF and DGN to a feature class in a Geodatabase.


ArcToolbox Export From Coverage Toolset
Export from Coverage Toolset

These tools convert coverages to a variety of commonly used geodata formats, among them DLG, DXF, Geodatabase, IGDS, SDTS, TIGER, shapefile, and VPF, to ESRI’s new geodata formats.

Wizards

Coverage to Geodatabase Wizard

Converts a coverage to the new ESRI feature dataset format.

Coverage to IGDS Wizard

Converts a coverage to an Interactive Graphics Design Software file.

Tools

Coverage to DFAD

Converts a set of coverages to a DFAD transfers file.

Coverage to DIME

Converts a coverage to a Dual Independent Map Encoding (DIME) file.

Coverage to DLG

Converts a coverage to a Digital Line Graph (DLG-3, optional format) file.

Coverage to DXF

Converts a coverage to a DXF file.

Coverage to Generate File

Converts a coverage to an ASCII file.

Coverage to Geodatabase

Converts a coverage to a feature dataset.

Coverage to IGES

Converts a coverage to an Initial Graphics Exchange Standard (IGES) file.

Coverage to MOSS

Converts a coverage to a MOSS export file.

Coverage to Shapefile

Converts feature attributes or INFO records to a shapefile.

Coverage to SLF

Converts a coverage to a Standard Linear Format (SLF) file.

Coverage to VPF

Converts a coverage to a coverage in Vector Product Format (VPF).

Export to Interchange File

Converts a coverage to an interchange file for transfer to another platform.

Export to SDTS

Converts a coverage to a Spatial Data Transfer Standard (SDTS), Topological Vector Profile or Point Profile transfer file.

Line Coverage to Grid

Converts coverage line features to a grid.

Point Coverage to Grid

Converts coverage point features to a grid.

Polygon Coverage to Grid

Converts coverage polygon features to a grid.


ArcToolbox Export From Geodatabase Toolset
Export from Geodatabase Toolset

These tools convert the ESRI Geodatabase formats to familiar ESRI formats.

Tools

Feature Class to Geodatabase

Converts a stand-alone feature class or a feature dataset feature class to a feature class in a Geodatabase feature dataset.

Geodatabase to Shapefile

Converts a feature class to a shapefile.

Geodatabase to Table

Converts a Geodatabase table to an INFO or a dBASE table.


ArcToolbox Export From Grid Toolset
Export from Raster Toolset

These tools convert grid data to other raster, vector, and ASCII formats.

Wizard

Raster to Geodatabase Wizard

Converts a raster dataset to a Geodatabase as a raster or raster table.

Tools

Export to Interchange File

Converts a grid to an interchange file for transfer to another platform.

Export to SDTS

Converts a grid to a Spatial Data Transfer Standard Raster Profile transfer file.

Grid to ASCII

Converts a grid to an ASCII file.

Grid to DEM

Converts a grid to a Digital Elevation Model.

Grid to Floating Point Data

Converts an integer grid to floating point numbers.

Grid to Image

Converts one grid or a set of grids to an image.

Grid to Line Coverage

Converts a grid with line features to a line coverage.

Grid to Point Coverage

Converts a grid with point features to a point coverage.

Grid to Polygon Coverage

Converts a grid with area features to a polygon coverage.

Grid to Tin

Converts a grid to a tin.

Raster to Geodatabase

Converts a raster dataset to a Geodatabase as a raster or raster table.

Raster to MrSID

Converts a raster dataset into a MrSID encoded image.


ArcToolbox Export From INFO Toolset
Export from Table Toolset

These tools convert INFO tables to common database table formats.

Wizard

Route Event Table to Feature Class Wizard

Converts a Route Event Table to a Geodatabase feature class.

Tools

Export to Interchange File

Converts an INFO table to an interchange file for transfer to another platform.

INFO to dBASE

Converts an INFO table to a dBASE table.

INFO to DBMS

Converts an INFO table to a DBMS table.

Table to Geodatabase

Converts an INFO or a dBASE table to a Geodatabase table.

Table to Point Coverage

Converts an INFO table, dBASE table or text file containing X and Y coordinates to a point Coverage.


ArcToolbox Export From Shapefile Toolset
Export from Shapefile Toolset

These tools convert shapefiles to common geodata formats, including the new ESRI .

Wizard

Shapefile to Geodatabase Wizard

Converts a shapefile to a stand-alone feature class, a feature class in a feature dataset or appends the feature class to a feature dataset.

Tools

Shapefile to AGF file

Converts a shapefile to an Atlas GeoFile (AGF) for use with Atlas GIS.

Shapefile to Coverage

Converts a shapefile to a coverage.

Shapefile to DXF

Converts a shapefile to an AutoCAD ASCII Drawing Interchange (DXF) file.

Shapefile to Geodatabase

Converts a shapefile  to a stand-alone feature class, a feature class in a feature dataset or appends the feature class to a feature dataset.


ArcToolbox Export From Tin Toolset
Export from Tin Toolset

These tools convert tin data to various formats.

Tools

Export to Interchange File

Converts a tin to an interchange file for transfer to another platform.

Tin to Coverage

Converts a tin to a coverage.

Tin to Grid

Converts a tin to a grid.

Tin to VRML

Converts a tin to VRML (Virtual Reality Modeling Language) format.


ArcToolbox Import To Coverage Toolset
Import to Coverage Toolset

These tools convert a variety of frequently used geodata formats to coverages, among them DLG, DXF, Etak, IGDS, SDTS, TIGER, shapefile, and ESRI's new geodata formats.

Wizards

DLG to Coverage Wizard

Converts a Digital Line Graph (DLG) file to one or several coverages.

DXF to Coverage Wizard

Converts a Drawing Exchange File (DXF) to a coverage.

Generate to Coverage Wizard

Converts an ASCII file to a coverage or adds features to an existing coverage.

IGDS to Coverage Wizard

Converts an Interactive Graphics Design Software file to a coverage.

Import SDTS Wizard

Converts a SDTS transfer file to one or several coverages or grids.

TIGER to Coverage Wizard

Converts a TIGER/Line™ file into one or several coverages.

Tools

DFAD to Coverage

Converts a DFAD transfer file to a set of coverages.

DIME to Coverage

Converts a DIME file to a coverage.

ETAK to Coverage

Converts an Etak MapBase file to a coverage.

Grid to Line Coverage

Converts a grid representing raster linear features to a line coverage.

Grid to Point Coverage

Converts a grid representing raster point features to a point coverage.

Grid to PolygonCoverage

Converts a grid to a polygon coverage.

Import from Interchange File

Converts an interchange file to a coverage, or ArcInfo dataset.

MOSS to Coverage

Converts a MOSS export file to a coverage.

SDTS Point to Coverage

Converts SDTS Point data to an ArcInfo point coverages.

Shapefile to Coverage

Converts a shapefile to a coverage.

SLF to Coverage

Converts a Standard Linear Format file to a coverage.

Table to Point Coverage

Converts an INFO table, dBASE table or text file containing X and Y coordinates to a point Coverage.

Tin to Coverage

Converts a tin to a coverage.

VPF to Coverage

Converts a VPF coverage or tile to a coverage or a VPF table to an INFO table.


ArcToolbox Import To Geodatabase Toolset
Import to Geodatabase Toolset

These wizards and tools convert familiar ESRI data formats to the ESRI Geodatabase formats.

Wizards

Coverage to Geodatabase Wizard

Converts a coverage to a feature dataset.

Raster to Geodatabase Wizard

Converts a raster dataset to a Geodatabase as a raster or raster table.

Route Event Table to Feature Class Wizard

Converts a Route Event Table to a Geodatabase feature class.

Shapefile to Geodatabase Wizard

Converts a shapefile to a stand-alone feature class, a feature class in a feature dataset or appends the feature class to a feature dataset.

Tools

CAD to Geodatabase

Converts common Computer-aided Drafting (CAD) file formats, among them DXF and DGN to a feature class in a Geodatabase.

Coverage to Geodatabase

Converts a coverage to a feature dataset.

Feature Class to Geodatabase

Converts a stand-alone feature class or a feature dataset feature class to a feature class in a Geodatabase feature dataset.

Shapefile to Geodatabase

Converts a shapefile  to a stand-alone feature class, a feature class in a feature dataset or appends the feature class to a feature dataset.

Table to Geodatabase

Converts a dBASE or an INFO table to a Geodatabase table.

VPF to Geodatabase

Converts a VPF feature class to a stand-alone geodatabase feature class, a geodatabase feature class in a feature dataset or appends the new geodatabase feature class to a feature dataset.


ArcToolbox Import To Grid Toolset
Import to Raster Toolset

These tools convert vector, raster, and ASCII data to grid format.

Wizards

Import SDTS Wizard

Converts a SDTS transfer file to one or several grids.

Tools

ADRG to Grid

Converts an ARC Digitized Raster Graphics image to a grid or grid stack.

ASCII to Grid

Converts an ASCII file to a grid.

DEM to Grid

Converts a Digital Elevation Model to a grid.

DTED to Grid

Converts a Digital Terrain Elevation Data file to a grid.

Floating Point Data to Grid

Converts floating point numbers to an integer grid.

Image to Grid

Converts an image to a grid or grid stack.

Import from Interchange File

Converts an interchange file to a grid.

Line Coverage to Grid

Converts coverage line features to a grid.

Point Coverage to Grid

Converts coverage point features to a grid.

Polygon Coverage to Grid

Converts coverage polygon features to a grid.

SDTS Raster to Grid

Converts SDTS GRID data to an ArcInfo grid.

Tin to Grid

Converts a tin to a grid.


ArcToolbox Import To INFO Toolset
Import to Table Toolset

These tools convert attribute data in common table formats to INFO format.

Tools

dBASE to INFO

Converts a dBASE table to an INFO table.

DBMS to INFO

Converts a DBMS table or view to an INFO table.

Geodatabase to Table

Converts a Geodatabase table to a dBASE or an INFO table.

Import from Interchange File

Converts an interchange file to an INFO table.

OLE DB to Table

Converts OLE DB tables to INFO and dBASE tables.


ArcToolbox Import To Shapefile Toolset
Import to Shapefile Toolset

These tools convert shapefiles to common geodata formats, including the new ESRI formats.

Wizards

Route Event Table to Feature Class Wizard

Converts a Route Event Table to a feature class.

Tools

AGF to Shapefile

Converts an Atlas GeoFile (AGF) to a shapefile.

Coverage to Shapefile

Converts a coverage to a shapefile.

Geodatabase to Shapefile

Converts a Geodatabase feature class to a shapefile.

MIF to Shapefile

Converts a MapInfo Interchange Format (MIF) file into a shapefile.


ArcToolbox Import To Tin Toolset
Import to Tin Toolset

These tools convert coverage, grid, and interchange file data to tin format.

Wizard

Create Tin Wizard

Creates a tin from one or more coverages or generate files.

Tools

Grid to Tin

Converts a grid to a tin.

Import from Interchange

Converts an interchange file to a tin.


ArcToolbox Data Management Tools
The Data Management Tools

The data management tools are a collection of toolsets that are used to define features and attributes and prepare coverages for spatial and attribute analysis.

Toolsets

Aggregate Toolset

These tools join adjacent coverages and their features.

COGO (Coordinate Geometry) Toolset

These tools create COGO coverages and related attributes, calculate COGO attribute values, and determine the legal area of a parcel.

Composite Features Toolset

These tools create composite features from line and polygon data.

Generalization Toolset

These tools simplify the geometry of line, polygon and region data.

Geodatabase Toolset

These tools create datasets in the new ESRI feature dataset format.

Projections Toolset

These tools define and change projections and register geodatasets to real world location.

Tables Toolset

These tools define a table and its items, perform common item editing, and join tables.

Topology Toolset

These tools clean up data by removing, splitting, and merging features and creating and updating feature topology.


Merging coverages with ArcToolbox
Aggregate Toolset

These tools join adjacent datasets and merge neighboring features.

Wizard

Append Wizard

Guides users through appending and joining adjacent coverages.


ArcToolbox Coordinate Geometry Toolset {COGO]
COGO (Coordinate Geometry) Toolset

These tools create COGO coverages and related attributes, calculate COGO attribute values, and determine the legal area of a parcel.

Tools

Add COGO Items

Adds empty COGO attributes to a line coverage.

Calculate COGO Attributes

Calculates COGO attribute values for two-point lines and curves.

Calculate Legal Area

Calculates the legal area, legal perimeter, and closure error for parcels, using COGO attributes.

Create COGO Coverage

Creates a new line coverage with COGO attributes, or a COGO point coverage.


ArcToolbox Composite Features Toolset
Composite Features Toolset

These tools create composite features from line and polygon data.

Tools

Line Coverage To Region

Creates preliminary regions from lines or appends preliminary regions to the specified, existing region subclass.

Line Coverage To Route

Creates a route system from lines or appends lines to the specified, existing route system.

Polygon Coverage To Region

Creates a region subclass from a polygon coverage.

Region To Polygon Coverage

Creates polygons from a region subclass and includes a table with data of overlaps.


ArcToolbox Generalization Toolset
Generalization Toolset

These tools simplify the geometry of line and polygon data.

Tools

Create Centerlines

Produces centerlines (single lines) from dual-line features, such as road casings, based on specified width tolerances.

Dissolve

Merges adjacent polygons, lines or regions which have the same value for a specified item.

Dissolve Regions

Creates a region subclass by merging polygons or regions that have the same value for a specified item.

Find Building Conflicts

Searches a coverage for overlapping and closely together buildings, based on a specified distance, and records the occurrences.

Simplify Buildings

Simplifies the footprint of buildings and creates a preliminary region for each simplified building.

Simplify Lines

Reduces details from lines based on a specified tolerance and simplification method.


ArcToolbox Geodatabase Toolset
Geodatabase Toolset

These tools create datasets in the ESRI feature dataset format.

Wizard

Build Geometric Network Wizard

Builds a linear network, such as streets or utilities, from an ESRI Geodatabase dataset’s lines and intersections. It supports complex edges and weights for network feature attributes.


ArcToolbox Linear Referencing Toolset
Linear Referencing Toolset

These tools create and maintain linear references.

Tools

Line Coverage To Route

Creates a route system from lines or appends lines to the specified, existing route system.

Route Event Table to Feature Class Wizard

Converts a Route Event Table to a Geodatabase feature class.


ArcToolbox Projections Toolset
Projections Toolset

These tools define a geodataset's coordinate system information if it is missing, modify a geodataset's existing coordinate system information, and convert a geodataset from one coordinate system into a different coordinate system.

Wizards

Define Projection Wizard (coverages, grids, TINs)

Assists in recording or modifying the parameters of standard and custom projections of a coverage, grid or TIN and stores the information in the .prj file. Use this wizard if your geodataset does not have a defined projection and .prj file.

Desktop Define Projection Wizard (shapefiles & geodatabase)

Wizard to assist in defining the coordinate system of shapefiles, feature classes and feature datasets.

Desktop Project Wizard (shapefiles & geodatabase)

Wizard for projecting shapefiles, feature classes and feature datasets to a different coordinate system.

Project Wizard (coverages, grids)

Projects a coverage or grid using the information stored in the .prj file. It also assists in changing a coverage or grid’s projection and projection parameters as well as in transforming its datum and spheroid.

Tool

Adjust

Adjusts or rubber sheets a coverage or grid’s features in either direction along the links in a link coverage or link file.

Transform

Scales, skews, rotates, and shifts coverage coordinates using an affine, similarity or projective transformation.


ArcToolbox Tables And Items Toolset
Tables Toolset

These tools define an INFO table, edit items, and join INFO tables.

Tools

Add from ASCII

Appends attribute records from an ASCII file to a table.

Add XY Coordinates

Adds the items X-COORD and Y-COORD for labels or points to the Input coverage PAT or for nodes to the Input coverage NAT and calculates their values.

Copy Items

Copies selected items to a new table.

Join Tables

Joins two tables based on a relate item.

Update IDs

Assigns a polygon’s User ID to its label point.


ArcToolbox Topology Toolset
Topology Toolset

These tools clean up data by snapping, removing, splitting, and merging features and creating and updating feature topology.

Tools

Build

Creates or updates feature attribute tables and defines topology. It also synchronizes polygon User-IDs with their label points’ User-ID.

Centroid Labels

Moves a polygon’s label point to its center, or inside its visible border.

Clean

Creates topology for lines or polygons—this may include coordinate editing—and creates or updates their attribute tables. It splits intersecting lines, removes dangles, undershoots and slivers.

Clean Regions

Simplifies a region coverage by merging polygons and deleting duplicate arcs not needed to define regions, using one or more selection expressions.

Create Polygon Labels

Creates polygon label points and assigns each an User-ID.

Create VPF Tile Topology

Creates cross-tile topology for a single coverage tile or all tiled coverages in a Vector Product Format (VPF ) database library.

Renumber Nodes

Updates arc-node topology by renumbering the from-nodes and to-nodes of each arc, and updates the FNODE# and TNODE# items in the arc attribute table. Also dissolves coincident and duplicate nodes into single nodes.


My Tools in ArcToolbox
My Tools

The toolset serves as a location to organize and access frequently used tools and to add custom tools. Any tool in the ArcToolbox tree can be added to My Tools by selecting the tool and then choosing “Send to” from the context menu. All custom tools are automatically added to My Tools or any of its user-defined subcategories.

Wizard

Add Custom EXE Wizard

Adds a user-created tool (.exe) to ArcToolbox’s My Tools toolset.

Tool

Run Geoprocessing AML

Executes an AML created with ArcToolbox or the Arc module.


Centroid Labels

Moves label points for coverage polygons to the centroids of the polygons, or to the inside of polygon borders.

Two Label position options are available:

Allow labels outside the polygons – moves label points to the centroids of the polygons.

Force labels inside the polygons – moves label points to the centroids of the polygons, but keeps labels inside polygon borders when the centroid falls outside the polygon border.

The centroid of a polygon may not fall within the polygon borders. For example, centroids for narrow, curved street polygons and irregularly shaped (usually 'L' or 'C' shaped) lot polygons will fall outside their borders. Use Force labels inside the polygons to prevent the centroids from being placed outside their polygon’s border.

Notes

Polygon centroids are often the best location for text placement in parcel coverages. The centroids of tiers of regularly shaped lots will often line up, providing aligned places for lot number or parcel ID text.

If a polygon has more than one label point, only the first one will be moved.

Label points are not created by the tool; it moves existing labels.

You might want to run Centroid Labels after running the Create Polygon Labels tool, as its scan-line methodology for label placement can produce irregular results for regularly shaped polygons.

Related Topics


The polygon coverage with label points you want to move.


Choose where you want to place the label points.

Allow labels outside the polygons – places the label point at the center of a polygon. The center of a narrow or irregular-shaped polygon, such as a street, may be placed outside its visible border.

Force labels inside the polygons – places the label point inside the visible border of a narrow or irregular-shaped polygon, such as a street. NOTE: The label point will most likely not be at the polygon’s center.


Clean

Builds polygon and arc-node topology by performing a geometric analysis on the Input coverage arcs and label points to identify coverage nodes and polygons. While processing, Clean…

Finds intersections between arcs, splits the arcs and codes the intersections as nodes (i.e., arc endpoints).

Merges coordinates within the Fuzzy tolerance of each other. Because the fuzzy tolerance actually moves arc vertices, understanding its relationship to coverage resolution is important.

Creates the list of arcs that define each polygon’s boundary, numbers the nodes, and establishes the From-node and To-node for each arc as well as the internal polygon numbers to the left and right of each arc.

Deletes dangling arcs that are shorter than the specified Dangle length.

Builds a polygon attribute table (PAT) or an arc attribute table (AAT) depending on the option used. It calculates the area and perimeter for each polygon and stores this information along with the polygon internal number and User-ID in the PAT. If the Input coverage already has a PAT, the polygon’s original internal number is used to join any additional items in the PAT to the output coverage PAT.

Clean provides two options to create topology:

Create polygon topology

Create line topology

Notes

When the Output coverage is the same as the Input coverage, the Input coverage is replaced. To maintain the Input coverage, name the Output coverage differently.

The internal number of each Input coverage feature is used to relate attribute information from the input feature attribute table to the Output coverage to ensure that the attributes are properly joined into the output feature attribute tables. Feature User-IDs do not have to be unique to ensure that each input feature keeps its attributes in the Output coverage.

Clean maintains the following in the Output coverage (if it exists in the Input coverage):

Node attribute table (NAT). It is updated and attribute values for new nodes are set to zero.

Annotation

Projection file

Clean does not maintain the following in the Output coverage (if it exists in the Input coverage):

Link features

Item indexes. To create an item index, access the item from ArcCatalog.

Clean and Build are alike in that they both define topology. But Clean uses a fuzzy tolerance and can therefore detect and resolve intersections. Build does not adjust any coordinates.

The tool cannot be executed on a region coverage that contains unclosed regions; processing stops upon detecting the first unclosed region.

Do not use Clean on a COGO coverage. Any arcs that are split by Clean will not have their COGO attributes updated. For example, an arc with a DISTANCE item value of 100 that is split will give the two new arcs DISTANCE values of 100. Use the Build tool instead and resolve any overlapping arcs in ARCEDIT using COGO.

Input coverage should have a defined projection.

Clean requires free disk space of up to 13 times the size of your Input coverage for temporary files. They are created in your current workspace. Use the ARCTMPDIR environment variable if you want to change this directory setting.

Related Topics


The coverage you want to clean.


The coverage you will create.

NOTE: To maintain the Input coverage, name the Output coverage differently.


Dangle length is the minimum length allowed for dangling arcs. Clean deletes dangling arcs that are shorter than the dangle length. The value displayed here is read from the Input coverage; it is 0 if no value is available from the Input coverage. Its unit of measure is that of the Input coverage. Change this value to suit your needs.

A dangle length of 0 is recommended for Line features. For Poly, we recommend a dangle length of 0.05” (0.127 cm) or the equivalent in coverage units. Negative values are not accepted.


Fuzzy tolerance is the minimum distance within which coordinates, arcs, and intersections are merged into one and the other is deleted. The value must be greater than 0.

The value displayed here is read from your Input coverage and will be applied to the coverage you create. Its unit of measure is that of the Input coverage. Change this value to suit your needs.


Choose the Feature class you want to clean.

Poly creates polygon topology and a PAT. If there is an AAT, it is rebuilt.

Line creates arc-node topology and an AAT.


How to set a temporary directory (ARCTMPDIR) for Clean

1	Open the Control Panel (Start menu: Settings).

2	Open the System folder.

3	On the System Properties form click the Environment tab.

4	Type in the Variable field: ARCTMPDIR

5	Type in the Value field: < … the directory path … >

6	Click Set.

7	Click OK to finish.


Create polygon topology:

Polygon topology and a polygon attribute table (PAT) are created. If there is an AAT, it is automatically updated. One additional polygon, the background or universe polygon, is also created.

Label points are required if you want non-zero polygon User-IDs and if you want to maintain polygon attributes. If a polygon has more than one label point, one is arbitrarily chosen to assign the User-ID.

Route systems are maintained, and the SEC and RAT are updated with adjustments for splitting and arc renumbering. But routes and sections are deleted if they are attached to arcs that are merged because of the fuzzy tolerance setting.

Sections are split and their arcs and measures on the arcs are updated.

Region topology is maintained. If the Input coverage has preliminary region topology, PAT and PAT<subclass> are created .


Create line topology:

Arc-node topology and an AAT are created or updated.

An existing PAT is not updated.

Route systems are maintained, and the SEC and RAT are updated with adjustments for splitting and arc renumbering. But routes and sections are deleted if they are attached to arcs that are merged because of the fuzzy tolerance setting.

Sections are split and their arcs and measures on the arcs are updated.

Regions and region subclasses are deleted.


Dangle length is the minimum length allowed for dangling arcs. A dangling arc is one that has the same polygon internal number on both its left and right sides, and ends in a dangling node.

Clean compares the length of dangling arcs against the dangle length and deletes those that are shorter than the dangle length.

We recommend a dangle length of

0.05” (0.127 cm) or the equivalent in coverage units for Feature class Poly

0 for Feature class Line

Negative values are not accepted.


Fuzzy tolerance represents the minimum distance within which coordinates, arcs, and intersections are merged into one. Two or more nodes or vertices within the fuzzy tolerance of each other become one coordinate point; the other vertices are deleted. It ensures that spatial features such as streets connect and areas such as parcels close so that relationships between spatial features are accurate.

The fuzzy tolerance determines the resolution of the Output coverage, because it moves and deletes coordinates such that no two coordinates in the Output coverage will be within this distance of each other.

A fuzzy tolerance that is too small can cause two kinds of problems:

Clean may not be able to resolve congruent arc segments, i.e., parallel arc segments that are within the fuzzy tolerance of one another.

Existing slivers or undershoots may not be cleaned successfully.

A fuzzy tolerance that is too large can cause two kinds of problems:

Polygons are collapsed that must not be collapsed.

Arcs are merged that must not be merged.

  How the default fuzzy tolerance is calculated.

  How to determine a fuzzy tolerance based on automation scale and digitizer extent.

  How to determine a fuzzy tolerance based on geodataset extent.


Input coverage should have a defined projection

Do not run Clean on a geographic coverage. Geographic coverages have units in decimal degrees, decimal seconds, radians, etc. These units are designed to measure angles. They do not measure distances. They represent a spherical coordinate system and should not be confused with a 2D rectilinear coordinate system upon which tools like Clean, Buffer, Union as well as all other overlay processes are designed to work. You can use the Project Wizard to first project your geographic cover to a suitable projection to convert your angles of latitude/longitude using angular units to a 2D rectilinear Cartesian coordinate system using rectilinear units like Feet, Meters, Kilometers, etc.


 No help available (Arc Toolbox 9999999)


Clean Regions

Reduces the number of polygons and arcs to the minimum number required to define the regions, by merging polygons and deleting selected arcs. Adjacent polygons are merged if their item values, including the User-ID, are identical; they are components of the same region; and any arc along the shared border is selected for removal. Arcs become candidates for removal if they are in the selected set as determined by a query or selection file.

If your Input coverage has an arc attribute table (AAT), you may either Build a query or Use selection file.

If your Input coverage has no AAT, you may either Use selection file or choose All arcs. With All arcs, the tool automatically selects all arcs and deletes those not needed to create regions.

  How to build a query

  How to edit a query

Notes

If the selected arcs remove the border between two polygons, any other border arcs between these two merged polygons will be removed as well, even though they do not meet the selection criteria.

To ensure that polygons that are to be merged have the same item values, you may have to set the User-ID in the polygon attribute table (PAT) to a common value before using the tool.

Arcs may be joined when they meet at pseudo nodes created by the merger of two polygons. Arcs meeting in a pseudo node will not be joined when (1) there is an NAT and item values for the pseudo node are not blank or zero, and (2) item values for the candidate arcs do not agree for any item in the AAT.

Related Topics


The region coverage with polygons you want to merge.


The coverage you will create. Name the Output coverage differently if you want to maintain the Input coverage.


Choose how you want to select arcs for removal.

Build a query – uses the Query Builder to create one or more logical expressions to select the arcs you want. Requires the existence of an AAT.

Use selection file - uses a pre-existing file that identifies the features you want to select. Can be used with or without an existing AAT.

All arcs - selects all arcs in a coverage with no AAT.


Opens the Query Builder to build or edit one or more query expressions.


Lists the selection expressions you have built for removing arcs.


 A selection file identifies the arcs you want to delete based on one or more attribute/value pairs. This file is created in ArcPlot and must already exist. A selection file is useful if you want to apply multiple queries to the same selected feature class.


How to create a selection expression for the Region clean tool
How to build a query

All features in the Input coverage are divided into two sets: a selected set and an unselected set. The selected set comprises the features to be merged, extracted or deleted. At the start of the Clean Regions, Query Regions, Eliminate and Select tools, and the Create Tin Wizardand Extract Wizard, all features are selected. You must use a query to identify the features to be in the final selected set.

1	Click [image] to open the Query Builder.

2	Choose a Selection method:

 reduces the selected set of records with a selection expression to those that meet its criteria. If no selection expression follows, the selected set will be empty. To see examples, click [image].

 adds unselected records that meet the selection expression criteria to the currently selected set. If no selection expression follows, the selected set will contain all features. To see examples, click [image].

 reverses the current selection to the unselected set.
NOTE: Switch is always used by itself. Using Switch twice in a row returns you to the initially selected set.

3	Choose an item from the Items list; for example, LENGTH.
(Notice that the Values list on the right is populated.)

4	Choose an Operator from those available, for example,  [image].

5	Choose a value in the Values list, for example, 5000.
(Notice that the Current expression textbox is updated with every selection you add.)

6	To extend or constrain your expression, choose a Connector such as  [image]  or  [image]  and repeat steps 3 through 5, and possibly 6 as needed.

7	Click  [image]  to add your expression to the list.

8	Repeat Steps 3 through 7 to build additional expressions in your query.

 moves the selected expression up. The expressions are processed in the order they are listed.

 moves the selected expression down. The expressions are processed in the order they are listed.

 saves your Query.

 opens a browser to retrieve a saved Query.

 deletes the selected Query or Selection expression from the list.


Subset query examples

Subset creates a subset of the currently selected set by reducing it to those features that meet its criteria.

Subset ROAD-NAME IN {'MAIN','ELM','15TH'} AND ROAD-TYPE IN {10,15,20->25}
interprets as “Of the selected set ‘Roads’, select the subset containing all roads whose ROAD-NAME is MAIN, ELM, or 15TH AND the subset containing all roads with a ROAD-TYPE value equal to 10 or 15 or between 20 and 25, inclusively.”

Subset FLOW >= 10 AND WIDTH <= 34.5
interprets as “Of the selected set ‘pipes’, select the subset containing all pipes with a flow rate greater than or equal to 10 and a pipe width less than or equal to 34.5 inches.”

Subset TAX <= 89 AND TAX > 12 OR ZONE = 'RW2'
interprets as “Of the selected set ‘buildings’, select the subset containing all buildings with a tax code larger than 12 and less than or equal to 89 or that are in zone RW2.”

Subset ZIPCODE like '9237*'
interprets as “Of the selected set ‘zip codes’, select the subset containing all zip codes that start with 9237.”

Subset F-NAME contains 'JOHN'
interprets as “Of the selected set ‘property owners’, select the subset containing all property owners whose first name contains the name John.”


Add query examples

Add adds unselected features to the currently selected set.

Add VALUE > YIELD
evaluates to “Add all records whose Value is larger than Yield to the currently selected set.”

Add DEPTH IN {90,120,400,600->900}
evaluates to “Add all records whose Depth value is contained in the group: 90, 120, 400, and 600 through 900, to the currently selected set.”

Add NAME like 'MC*'
evaluates to “Add all names that start with the letters MC to the currently selected set.”


How to edit a selection expression for the Region clean tool
How to edit a query

1	Click [image] to open the Query Builder.

2	Choose the query you want to edit.

3	Use the cursor to clear all or part of the expression.

4	Choose the appropriate pieces from the Items, Operators, and Values lists.

5	Click  [image]  to replace the expression in the list.

6	Repeat steps as needed.

7	Click OK to return the edited query to the tool or wizard.


Clip

Uses the outside polygon boundary of a Clip coverage to cookie-cut features and attributes from an Input coverage.

Clip discovers the feature classes in the Input coverage and offers the available clipping methods:

Poly – polygons and region subclasses are clipped and a PAT saved. Label points for remaining polygons are moved only if their original location falls outside the clipping boundary. Route-systems are ignored.

Line – arcs are clipped and an AAT saved. Route-systems are maintained.

Point – points are clipped and a PAT saved.

Poly & Line (Net) – polygons and arcs are clipped, and their PAT and AAT are saved. Route-systems and regions are maintained and clipped.

Line & Point (Link) – arcs and points are clipped, and their AAT and PAT are saved. Route-systems are maintained.

Geometry – points, arcs, and annotation in a coverage with or without topology (no attribute files) are clipped. Route-systems are maintained but regions, PAT and AAT are not saved.

Notes

Annotation is saved if its lower-left starting point falls within the clipping polygon.

New nodes created on the clipping boundary have their attributes set to zero.

Route-systems are duplicated for arcs split into multiple pieces, and eliminated for removed arcs. The RAT<subclass>–ID item is the unique route identifier, and is used to remove duplicates. If you need to maintain all the user-defined attributes, make sure that all the route –IDs are unique before running CLIP, otherwise some user-defined attributes may be lost.

When all the regions are removed, the region subclasses are maintained as empty subclasses.

Data model content inherited by the output

How the default fuzzy tolerance is calculated

Processing planar graphs

Related Topics


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Feature classes

Feature attribute table items

User-IDs

Tics

Annotation

Node attribute table

Projection file


The coverage with features you want to clip.


The outer polygon of this coverage defines the clipping region.


The coverage you will create.


Choose the feature class you want to clip.

Poly – polygons and region subclasses

Line – arcs

Point – points

Poly & Line (Net) – polygons and arcs

Line & Point (Link) – arcs and points

Geometry – points, arcs, and annotation in a coverage with or without topology are clipped. Attributes are ignored.


The ArcToolbox’s main tool categories. Clicking the [image] expands the nodes into a treeview.


A search tool to locate a tool within the ArcToolbox’s tree. The panel displays all found instances.


Displays a brief description of the selected tool category, toolset, or tool.


Executes the tool.


Cancels execution and closes the tool.


Opens a help window showing an overview of how this tool works.


Enables the batch environment where multiple instances of the task can be performed from a single session.


Lists the parameters you selected for multiple executions of this tool.


The unit of measure for the fuzzy tolerance.


Opens a browser.


Executes the browser, closes it, and returns the selected dataset to the tool.


Cancels browser execution and closes it.


Lists the available disk drives.


Lists the available directories and datasets.


An available dataset.


Choose the dataset type(s) you want to use.


Up one level – moves you one directory up

List – displays data sources in a list

Details – displays detailed information about data sources


How the default fuzzy tolerance is determined
How the default fuzzy tolerance is calculated

Fuzzy tolerance is the minimum distance between coordinates in the output coverage. The tool calculates the minimum Fuzzy tolerance from the input coverages. Its unit of measure is that of the input coverages. The default is determined in this order:

1	Tolerance values are read from the existing coverage TOL file.

2	If no TOL file exists and the width of the BND is between 1 and 100, the tolerance is 0.002.

3	Otherwise, the tolerance is 1/10,000 of the width or height of the BND, whichever is greater.

How to determine a fuzzy tolerance


How to determine a fuzzy tolerance for single precision geodatasets
How to determine a fuzzy tolerance

Based on automation scale and digitizer precision

Based on geodataset extent


Based on automation scale and digitizer precision

The most accurate method for setting the fuzzy tolerance is based on its automation scale and the digitizer precision. This table lists standard automation scales and the corresponding fuzzy tolerance for an industry standard digitizer precision of 0.002”.

NOTE: The fuzzy tolerance always uses the unit of measure of the geodataset.

Automation scale of source data	Coverage coordinate units	Fuzzy tolerance (on the ground) at 0.002” digitizer precision
1:200 000	feet meters	33.333 10.160
1:100 000	feet meters	16.620   5.080
1:63 360	feet meters	10.560   3.210
1:25 000	feet meters	4.167  (4.000)   1.270  (1.219)
1:10 000	feet meters	1.668   0.508
1:5 000	feet meters	0.833   0.254
1:1 000	feet meters	0.167   0.051
1:500	feet meters	0.083   0.025

If you don't see the automation scale of your geodataset in the table, calculate the fuzzy tolerance with this equation:

Tolerance in feet  = ((automation scale * digitizer precision) /12)

Tolerance in meters = ((automation scale * digitizer precision) /12) * 0.3048


Based on the geodataset extent

If you don't know the automation scale of the coverage, an alternate method for setting the fuzzy tolerance is based on the coverage extent and uses the coordinate values stored in its BND. This table shows threshold values for various coverage extents:

Extent	Type of data content	Fuzzy tolerance (resolution)	Divide extent by
10	buildings/streets	0.001 m	10 000
100	census block	0.01m	10 000
1 000	census block/ tract	0.1 m	10 000
>1 000	city tract/town	0.1 – 0.9 m	10 000
10 000	city	1 m	10 000
>10 000	city/county	1 m	extent
100 000	county	1 m	100 000
1 000 000	state/small country	5 m	200 000
>1 000 000	continent to globe	10 m	1 000 000

If you don't see the extent of your geodataset in the table, here's how to calculate the fuzzy tolerance:

1	Determine the extent, that is, the larger of (xmax –xmin) and (ymax – ymin);

2	Determine a sensible resolution for the type of data content, e.g., census block, city, county, state, country, continent, global;

3	Determine the denominator to get the desired resolution. Use the resolution as fuzzy tolerance value.

The Fuzzy tolerance for double precision geodatasets is often smaller than that for single precision coverages, since they are frequently collected from precise sources such as surveying, engineering, and global positioning systems (GPS).


Planar graph processing
Processing planar graphs

When the Input coverage contains linear data belonging to different planar graphs, they will be maintained in the Output coverage.

For example, coincident or colinear arcs such as arcs representing utility cables at different levels or a road following a stream, the coincident and colinear line segments will be preserved. However additional vertices may be inserted.

In the case of intersecting arcs such as a road passing over a stream, nodes will not be inserted at the apparent intersection.


Single precision refers to the coordinate precision of a geodataset. It stores coordinate values with up to 7 digits. See also double precision.


Double precision refers to the coordinate precision of a geodataset. It stores coordinate values with up to 14 digits, captured with a precise measuring device such as a GPS. See also single precision.


Units of measure used by ArcToolbox

Units	Abbreviation

Millimeters	mm
Centimeters	cm
Meters	m
Kilometers	km
Inches	in.
Feet	ft.
Yards	yd.
Miles	mi.
Nautical miles	nm
Decimal degrees	DD
Radians
Undefined units


Add COGO Items adds empty coordinate geometry (COGO) attributes to a line coverage.


Add from ASCII appends attribute records from an ASCII file to a table.


Add Item adds an item to a table and assigns each the value zero or blank.


ADRG to Grid creates a grid or grid stack from a US NIMA ARC Digitized Raster Graphics (ADRG) image.


AGF to Shapefile creates a shapefile from an Atlas Geo file (AGF).


Append Wizard combines up to 500 adjacent coverages into one coverage.


ASCII to Grid creates a grid from an ASCII file.


Buffer creates a polygon coverage of buffers that surround features of a point, node, line or polygon coverage. Overlapping buffer areas are merged.


Buffer Regions creates buffer regions around grouped input coverage features. Overlapping buffer areas are maintained separately.


Buffer Wizard creates a polygon or region coverage of buffers that surround features of a point, node, line, polygon or region coverage.


Build creates or updates feature attribute tables and polygon or arc-node topology.


Build Geometric Network Wizard builds network topology for geodatabase feature classes.


Calculate COGO Attributes calculates COGO attribute values for two-point lines and curves.


Calculate Legal Area computes the legal area, legal perimeter, and closure error for parcels, using COGO attributes.


Centroid Labels moves a polygon’s label point to its center.


Clean creates a coverage with correct polygon or arc-node topology.


Clean Regions simplifies a region coverage by merging polygons and duplicate arcs not needed to define regions, using one or more selection expressions.


Clip uses the outside polygon boundary of a Clip coverage to cookie-cut features and attributes from an Input coverage.


Contour Wizard creates a coverage containing contours or isolines from a tin or grid.


Copy Items copies selected items to a new table.


Coverage to DFAD creates a DFAD transfer file from an ArcInfo workspace.


Coverage to DIME creates a DIME file in the standard U.S. Census Bureau format from the arcs in a line or polygon coverage.


Coverage to DLG creates a DLG-3 Optional format file from a coverage.


Coverage to DXF creates an AutoCAD Drawing Interchange File (DXF) from one or more coverages.


Coverage to Generate File creates a text file of x, y coordinates for a coverage.


Coverage to Geodatabase converts a coverage into a feature dataset.


Coverage to Geodatabase Wizard converts coverages into feature datasets.


Coverage to IGDS Wizard creates an Interactive Graphics Design Software (IGDS ) file from a coverage.


Coverage to IGES creates an Initial Graphics Exchange Standard (IGES) Version 3.0 uncompressed ASCII file from a coverage.


Coverage to Interchange File converts a coverage or other supported dataset to an interchange file for transfer to another platform running ArcInfo.


Coverage to MOSS creates a MOSS export file from a coverage.


Coverage to SDTS creates  a set of SDTS Topological Vector Profile (TVP) or Point Profile transfer file from coverages.


Coverage to Shapefile creates a shapefile from a coverage.


Coverage to SLF creates a Standard Linear Format (SLF) file from coverages.


Coverage to VPF creates a VPF table from an INFO table or a VPF coverage or VPF tile from a coverage.


Create Centerlines creates centerlines (single-lines) for dual-line features, such as road casings, based on specified width tolerances.


Create COGO Coverage creates a line coverage with COGO attributes or a point coverage.


Create Polygon Labels creates polygon label points.


Create Thiessen Polygons creates a coverage of Thiessen proximal polygons from coverage points.


Create Tin Wizard creates a tin from one or more coverages and/or 3D generate files.


Create VPF Tile Topology creates topology for an individual tile in a Vector Product Format (VPF) library or for the entire tiled library.


Cut & Fill summarizes the areas and volumes of change during a cut-and-fill operation on an area represented by two grids, one before and one after the cut & fill operation.


dBASE to INFO copies a dBASE data table into an INFO table.


DBMS to INFO creates an INFO table from a DBMS table or view.


Define Projection Wizard defines the projection for a geodataset or applies the projection definition of one geodataset to another one.


Define Table creates a table and defines its items.


DEM to Grid creates a DEM in USGS format to a grid.


DFAD to Coverage creates a set of coverages from a DFAD transfer file.


DIME to Coverage creates a line coverage and an ACODE attribute file containing DIME field attributes from a DIME file.


Dissolve simplifies a coverage by eliminating nodes along connected lines, or arcs between adjacent polygons, that have the same Dissolve item value.


Dissolve Regions creates a region subclass by aggregating polygons or regions with the same value for a specified Dissolve item.


DLG to Coverage Wizard creates one or more coverages from a Digital Line Graph (DLG) file in either Standard or Optional format.


DTED to Grid creates a grid from a United States National Imagery and Mapping Agency Digital Terrain Elevation Data (DTED) file.


DXF to Coverage Wizard creates a double-precision coverage from an AutoCAD Drawing Exchange File (DXF).


Eliminate eliminates polygons or lines from a coverage by merging them with adjacent features.


Erase creates a new coverage by overlaying the polygons of the Erase coverage with the features of the Input coverage.


ETAK to Coverage creates a coverage from an Etak MapBase file.


Export to Interchange File converts a coverage, grid, tin or INFO table to an interchange file for transfer to another platform running ArcInfo.


Extract Wizard creates a coverage by extracting features from a single or multiple Input coverages.


Find Building Conflicts searches a coverage for overlapping and closely together buildings, based on a specified distance, and records the occurrences.


Floating Point Data to Grid creates a grid from an IEEE floating point format, 32 bit signed file of binary floating point numbers.


Frequency searches an Input table for unique occurrences of one or more Frequency items.


Generalize Lines reduces details from lines based on a specified tolerance and simplification method.


Generate to Coverage Wizard creates a coverage from an ASCII file or adds features to a coverage.


Geodatabase to Coverage converts a feature dataset into a coverage.


Geodatabase to Shapefile converts a feature class into a shapefile.


Grid to ASCII creates an ASCII file from an integer or floating point grid.


Grid to DEM creates a Digital Elevation Model in the United States Geological Survey (USGS) format from a grid.


Grid to Floating Point Data creates a signed, 32-bit, binary file in IEEE floating point format suitable for data transfer to other applications from a grid.


Grid to Image creates a single-band or multi-band image from a a grid or a grid stack, respectively.


Grid to Interchange File converts a coverage, file, grid, or other supported dataset to an interchange file for transfer to another platform running ArcInfo.


Grid to Line Coverage creates a grid representing raster linear features to a line coverage.


Grid to Point Coverage creates a grid representing raster point features to a point coverage.


Grid to Polygon Coverage creates a polygon coverage from a grid from groups of contiguous cells having the same cell values.


Grid to Tin creates a tin from a grid.


Identity computes the geometric intersection of two coverages.  All features of the input coverage, as well as those features of the identity coverage that overlap the input coverage, are preserved


IGDS to Coverage Wizard creates a coverage from an Interactive Graphics Design Software (IGDS) file.


Image to Grid creates a grid or set of grids from an image.


Import from Interchange File converts an ArcInfo export interchange file.


INFO to dBASE creates a dBASE table from an INFO table.


INFO to DBMS creates a DBMS table from an INFO table.


INFO to Interchange File converts a coverage, INFO table, or other supported dataset to an interchange file for transfer to another platform running ArcInfo.


Interchange File to Coverage creates a coverage from an ArcInfo interchange file.


Interchange File to Grid creates a grid from an ArcInfo interchange file.


Interchange File to INFO creates an INFO table from an ArcInfo interchange file.


Interchange File to Tin creates a Tin from an ArcInfo interchange file.


Intersect computes the geometric intersection of two coverages. Only those features in the area common to both coverages will be preserved in the output coverage.


Join Tables joins two tables based on a relate item.


Line Coverage to Grid creates a grid from a line coverage.


Line Coverage to Region creates preliminary regions from arcs or appends preliminary regions to the specified region subclass.


Line Coverage to Route creates a route system from lines or appends lines to route system.


MIF to Shapefile creates shapefile from a MapInfo Interchange Format (MIF).


MOSS to Coverage creates a coverage from a file in MOSS export format.


Near computes the distance from every Input coverage point to the nearest Near coverage point, line or node within the maximum Search radius.


OLE DB to Table converts OLE DB tables to INFO and dBASE tables.


Overlay Wizard creates a coverage by computing the geometric intersection of two input coverages.


Point Coverage to Grid creates a grid from a point coverage.


Point Distance computes the point-to-point distance between each point in the From coverage and all points in the To coverage within a maximum Search radius.


Point Node transfers attributes from a point feature class to a node feature class.


Polygon Coverage to Grid creates a grid from a polygon coverage.


Polygon Coverage to Region creates one region in a region subclass for each polygon in the input polygon coverage.


Project Wizard converts a geodataset between two coordinate systems or copies the projection information from one geodataset to another.


Query Builder constructs one or more queries, composed of one or more selection expressions, to operate on the selected feature class.


Query Regions creates new regions based on the attribute values of input region or polygon layers and aggregates regions according to specified attribute items.


Rectify creates an image by scaling, skewing, rotating, and translating the Input image.


Region to Polygon Coverage creates polygons from a region subclass and includes a table with data on overlapping polygons.


Relate manager allows you to manage relates in the ArcToolbox. Available in the Tools menu.


Renumber Nodes updates arc-node topology by renumbering From- and To-nodes.


Run Geoprocessing AML executes an AML.


SDTS to Coverage Wizard creates one or more coverages from an SDTS Topological Vector Profile (TVP) or Point Profile transfer file.


SDTS to Grid Wizard creates an ArcInfo grid from an SDTS Raster Profile transfer file.


SDTS Raster to Grid creates an ArcInfo grid from a SDTS Raster Profile data set.


SDTS Point to Coverage creates an ArcInfo point coverage from SDTS Point data.


Select creates a coverage by extracting selected features from an Input coverage.


Shapefile to AGF creates an Atlas Geo file (AGF) from a shapefile.


Shapefile to Coverage creates a coverage from a shapefile.


Shapefile to Geodatabase converts a shapefile into a geodatabase feature class.


Shapefile to Geodatabase Wizard converts a shapefile into a geodatabase feature class.


Simplify Buildings simplifies the footprint of buildings and creates a preliminary region for each output building.


SLF to Coverage creates a coverage from a Standard Linear Format file.


Split clips an input coverage into multiple coverages.


Statistics Wizard performs standard attribute statistics.


Summary Statistics creates summary statistics for table items and saves them in an Output table.


Table to Geodatabase converts INFO and dBASE tables into geodatabase tables.


TIGER to Coverage Wizard creates one or more coverages from a set of U.S. Bureau of Census TIGER/Line files.


Tin to Coverage creates a coverage from a tin.


Tin to Grid creates a grid from a tin.


Tin to Interchange File converts a coverage, tin, or other supported dataset to an interchange file for transfer to another platform running ArcInfo.


Tin to VRML creates a VRML formatted file from a tin.


Transform scales, skews, rotates, and shifts coverage coordinates using an affine, similarity or projective transformation based on a set of tics.


Union creates a coverage by overlaying the polygons in the Union coverage with those in the Input coverage. Arcs are split at their intersection.


Update creates a coverage by overlaying two sets of features, using the polygons of the Update coverage to cookie-cut the features and their attributes from the Input coverage.


Update IDs assigns a polygon’s User-ID to its label point.


Visibility performs visibility analysis on a grid by determining how many observation points in a coverage can be seen from each region of the grid, or which regions can be seen by each observation point.


Volume calculates the area and volume of a tin.


VPF to Coverage creates a VPF table into an INFO table or it creates either a VPF coverage or VPF tile into an ArcInfo coverage.


Coverage units, also referred to as map units, are the units of measure in which the coverage data is stored. Standard values are meters, feet, Decimal Degrees (DD). Other valid units of measure.


Enter the operation or tool name you want to search for.


Enter the ArcInfo command whose equivalent ArcToolbox tool you want to search for.


Enter the keyword or phrase describing the tool’s functionality you want to search for.


Finds occurrences of the text you entered in the Containing text, Command name, or Keyword box.


Clears the entry in the Containing text, Command name, or Keyword box so you can enter a new tool name, ArcInfo command, or keyword to search for.


Closes this dialog.


Lists the tool categories, toolsets, and tools currently visible in the ArcToolbox tree. Uncheck a main category to disable its display in the ArcToolbox tree. Click [image] to expand the tree and uncheck individual toolsets or tools you want to disable.


Uncheck to disable the tool description on the bottom of the ArcToolbox; or check to show the tool description.


Uncheck to disable the tool category help nodes in the ArcToolbox tree; or check to show the tool category help nodes.


Check to show ArcToolbox tool dialogs on top of all other application windows you have open, or uncheck to disable ArcToolbox tool dialogs being on top.


Check to activate remote processing on a Geoprocessing Server.


Check to activate scheduling of your remote processing on a Geoprocessing Server.


Lists the Geoprocessing Servers available for remote processing. Select the one you want to connect to.


Opens a dialog to add a Geoprocessing Server to the available server list.


Removes the currently selected Geoprocessing Server from the available server list.


Apply and save all the changes you have made.


Edit the connection properties of the currently selected server.


Test the Geoprocessing Server connection. The button is disabled if the test is successful. An error message will be displayed if the test is unsuccessful and the button will remain enabled. Edit the connection properties of the server or your services file to correct an error.


Applies and saves all the changes you have made and closes the dialog.


Immediately applies the changes you have made and keeps the dialog open.


Enter a connection name such as myConnection1.


Enter the Geoprocessing Server you want to connect to.


Enter the Geoprocessing Server instance you want to connect to.


Enter the administrator password needed to access the Geoprocessing Server.


Enter your system login name to access the Geoprocessing Server.


Enter your password.


Applies and saves your entries and closes the dialog.


Lists all ArcToolbox jobs you have sent to one or more Geoprocessing Servers. Select one job to view details about its status and results, or to terminate its processing.


Opens a dialog to view status details about a selected job.


Opens a dialog to view result details about a selected job.


Removes the selected job from the list.


Lets you modify the selected job.


Permanently deletes the selected job from the server’s processing queue.


Run Geoprocessing AML

Runs an AML script containing Arc geoprocessing commands. This tool executes one or more AMLs that you created with any one of the ArcToolbox tools or wizards as well as some AMLs created by other means (e.g., using your text editor).

Important note: Your AML must contain menu interfaces or commands available only at the Arc: or Tables: prompts in ArcInfo. If the AML contains ArcEdit or ArcPlot commands, it will fail.

Notes

This tool is intended for experienced ArcInfo users who have created many geoprocessing scripts as AMLs that run Arc commands (such as BUILD, CLEAN, UNION, BUFFER, JOINITEM, CLIP, or data conversion commands.) It allows you to run your AMLs locally or remotely by taking advantage of ArcInfo's geoprocessing power as you know it, and at the same time use the interactive tools and capabilities of the new ArcInfo Desktop applications.

To use Tables commands, you must give a workspace command before entering Tables, otherwise the tool won't know where to start. For example, this AML was created with the Define Table tool:

/* Begin: Define Table
/* Aml script created with ArcToolBox for tool: Define Table
/* Editing this file may make it unreadable to the ArcToolbox
 Precision Single Highest
WORKSPACE C:\ozzie\testdata
TABLES
  DEFINE newtable1
  Item1
  8
  8
  I
  [unquote '']
  quit
/* End: Define Table


The AML script you want to run.


Standard Data Types

Binary (B) – whole numbers stored as binary integers (width of 2 or 4 bytes only). The maximum value for width of 2 is 32,767 and the minimum value is -32,768. The maximum value for width of 4 is 2,147,483,647 and the minimum is -2,147,483,648.

Character (C) – alphanumeric characters (maximum length 320).

Date (D) – dates in the form of MM/DD/YY or MM/DD/YYYY (item width is fixed at 8 and stored internally as YYYYMMDD).

Floating point (F) – decimal numbers stored in internal floating point representation (width of 4 or 8 bytes only). A 4-byte width is single precision real (approximately 7-9 digits of precision). An 8-byte width is double precision real (approximately 15-17 digits of precision). The maximum value for a 4-byte width is 3.402823466e+38, and the minimum positive value is 1.175494351e-38. The maximum value for an 8-byte width is 1.7976931348623158e+308, and the minimum positive value is 2.225073858507201e-308.

Integer (I) – integer stored as 1 byte per digit (width from 1 to 16). Maximum value possible is 9,999,999,999,999,998 and the minimum value is -999,999,999,999,999. If the value is negative, one byte of storage is used for the minus sign.

Numeric (N) – decimal numbers stored as 1 byte per digit, including a decimal point and a minus sign. The maximum width is 16.


Edit masks are rectangular areas defining the spatial extent of edits made on features in a coverage. The coordinates for these areas are stored in the MSK file. The Build and Clean tools remove this file.


The Universe polygon encompasses the area outside a coverage’s bounding box. It is always the first record in a PAT, its AREA value is always negative, and its User-ID value always 0.


No help available (ArcToolbox 9999999)


Connect to Database

Manages connections to external database management systems (DBMS).

To connect to an available database, select a database from the Available databases list, enter the Connect information, then click Connect.

Connection information for the databases.

  Oracle

  Informix

  Sybase

  Ingres

  Microsoft Access

  Microsoft SQLSERVER

Find out more about databases in ArcDoc, Working with Tables -> Using DBI.

Related Topics


Oracle

{<username>/<password>}

or

{<username>/<password>@<alias>}


Informix

{database}

or

{//<servicename>/<database>}

or

{<database>@<servicename>}


Sybase

{<user>/<password>}

or

{<username>/<password>/<servicename>}

or

{<username>/<password>/<server>/<database>}

or

{-Uusername -Ppassword -Ddatabase -Sserver -Cclient character set}


Ingres

{<database>}

or

{<vnode>::<database>}


Microsoft Access

{<datasource>}

or

{DSN=datasource}


Microsoft SQLSERVER

{<datasource>/<user>/<password>}

or

{"DSN=datasource;UID=user;PWD=password"}


Available databases lists the databases found in the $ARCHOME\database directory or in the local workspace.


Disconnect terminates the selected database connection.


Database definition displays the contents of the database definition file for the selected database.


Connect information is additional connection information not included in the database definition file. See the Connection information in the help file for parameters for specific databases.


Connect establishes a connection to the selected database using the parameters defined in the database definition file and the connection information.


Status displays the connection status of the selected database.


Close dismisses the Connect to Database tool.


Relate Manager

Manages the relate environment.

Fields in related tables can be used anywhere that an item name can be specified in ArcInfo.

Related Topics


Name - the relate name. It can be any alphanumeric string up to 8 characters long.


Database - the database that stores the related table.


Connect to Database - opens the Connect to Database tool which is used to establish a database connection.


Table - the table in the specified Database that you are relating to.


The available tables in the specified Database.


Column - the ‘Destination item’ in the relate. This is the field in the related Table that the Item is related to.


Item - the 'Source item' in the relate. This is the name of the item in the INFO table from which the relate is performed. This item must be formatted to be compatible with the Column.


Type - the type of relate performed. The Linear, Ordered, Link and Table options apply to relates between two INFO tables. The First option is a special case when relating an INFO table to an external DBMS table.

Linear - both tables can be sorted in any order. This option takes very long to execute on large data files. As a general rule, always create an index on the relate column of the related table before attempting a linear relate. This will significantly speed up the process and can be even faster than an ordered relate.

Ordered - the related table must be sorted by relate Column. This option uses a binary search instead of a sequential search (as performed by Linear) and results in much faster execution.

Link - both tables can be sorted in any order. The value for the Item indicates the record number of the related table. The record number of the related table is used as the relate column instead of the specified Column. This relate type executes the fastest because it can directly access records in the related table by record number.

Table - works the same as Ordered except in the way that mismatched values of the Item are matched to Column values. If an exact match is not found in the related table, the next highest relate value is returned. This way, the related table actually stores ranges of values. The related table must be sorted by the Column.

Sorting a feature attribute table on an item other than the <cover># is not recommended. If a feature attribute table is sorted on any item other than <cover>#, it must be sorted back on <cover># before any other ArcInfo operations are performed on it.

First - this applies to relates between an INFO table and an external DBMS table. If many records exist in the DBMS table with the same value for Column, only the first record of each value is matched (related) to the INFO item.


Access rights to the related table. The value determines whether the related table can be modified or only displayed.

Read and write access to the related table.

Read only access. The related table cannot be modified.

Auto access rights to the related table are the same as the source INFO table.


Open - opens a browser to select an INFO table that contains a set of pre-defined relates. When opening a relate to a RDBMS table, you must first connect to the RDBMS before the relate can be opened.


Save - opens a browser to specify an INFO table that will store the relates listed.


Delete - removes the specified relate from the list.


Add - adds the relate to the relate list.


Lock Manager

Locks are placed on coverages and coverage feature classes when ArcToolbox, ArcCatalog or ArcMap accesses them. Locks are necessary to maintain data integrity since a coverage can be simultaneously read by many applications but only one application may write to a dataset at a time. Multiple users or applications updating a coverage at the same time may result in corrupted data.

If a dataset you want to use in a tool or wizard is locked, you will have to wait until the lock has been released by the application that applied the lock. Use the Retry button to attempt to lock the dataset(s) after you correct the situation that may be causing the locking problem. Typically locking problems are caused when a tool requires a write lock for a coverage but another application has a read lock on the same dataset. A tool is unable to place a write lock on a coverage when someone else is has applied a read lock. Locks are applied to a coverage in the following situations:

A coverage feature class is being previewed in ArcCatalog using the Preview tab. ArcToolbox will be able to use it, once the dataset is not being previewed.

An ArcToolbox tool is processing the coverage, which is specified as input. Once the tool is finished the lock is released.

A coverage feature class has been added as a layer in an ArcMap map.

A query is being performed on a feature class in ArcMap. Once the query is complete, the lock is released.

The properties of a coverage or coverage feature class are being displayed in ArcCatalog and any changes made are being applied. Once the changes are complete, the lock is released.

Another person using the ArcInfo Lockmanager command has locked a coverage.

Refer to the white paper Multiple User Access for Coverages and Shapefiles to learn more about the ESRI lock manager and how it is used in ArcInfo.


Create an item index

1	In the ArcCatalog tree or list view (Contents tab), right-click the feature class with the item you want to index.

2	Click Properties.

3	Click the Items tab.

4	Select the item you want to index.

5	Click Add Index; this changes the value in the Indexed column to true.

6	Click Apply, then OK.

7	Repeat steps 4 through 6 to index another item.


Edit an item

1	In the ArcCatalog tree or list view (Contents tab), right-click the feature class with the item you want to edit.

2	Click Properties.

3	Click the Fields tab.

4	Select the item you want to edit.

5	Click Edit…; this opens the Edit Item window.

6	The white fields are available for editing. Change the values you need to.

7	Click OK.

8	Repeat steps 4 through 7 to edit another item.


Add an item

1	In the ArcCatalog tree or list view (Contents tab), right-click the feature class you want to add an item to.

2	Click Properties.

3	Click the Fields tab.

4	Click Add…; this opens the Add Item window.

5	The white fields are available for editing. Enter the values you need to.

6	Click OK.

7	Repeat steps 4 through 6 to add another item.


Delete an item

1	In the ArcCatalog tree or list view (Contents tab), right-click the feature class with the item you want to delete.

2	Click Properties.

3	Click the Fields tab.

4	Select the item you want to delete.

5	Click Delete.

6	Click Apply, then OK.

7	Repeat steps 4 through 6 to delete another item.


Using lookup tables

A lookup table is a special kind of INFO table used to categorize item values. Each category has an item value for another item such as a buffer distance.

Each lookup table must contain at least two items:

item - an item from the coverage’s feature attribute table whose values are used as a key to values in the lookup table. The item can be defined as character or numeric. The lookup table must be sorted on this item in ascending order. This item is called Distance item in the buffer tools, and Value item in the conversion tools. This item must be named and defined in exactly the same way in both the feature attribute table and lookup table.

lookup item - the item containing the value associated with each category of the item in the feature attribute table. The Buffer and Buffer Regions tools and the Buffer Wizard require that the lookup item is numeric and is named DIST. The conversion tools Line Coverage to Grid, Point Coverage to Grid and Polygon Coverage to Grid require that the lookup item is numeric and is named CODE.

When a tool reads a value for a specified item in a feature attribute table, it will look for a match in the lookup table. If it does not find a matching value, it will use the record with the next greater value for the item. Features with lookup item values exceeding the last record in the lookup table are assigned to the last record.

Notes

Lookup tables can be created with the Define Table tool.

Example with a character Distance item

Example with a numeric Distance item

Related Topics


Example with a character Distance item

A line coverage has an item named STREETCODE. The lookup table STREET.LUT also has an item named STREETCODE, and each record assigns a buffer distance to the STREETCODE value:

   STREETCODE     DIST
     AVE           25
     BLVD          40
     HWY          100
     ST            10

The item called STREETCODE must be defined the same as the STREETCODE item in the coverage AAT. The Buffer tool will read the value for the STREETCODE item in the feature attribute table. If the value is BLVD, it finds BLVD in the lookup table, then uses a buffer distance of 40 for that feature.


Example with a numeric Distance item

Fault zones are ranked from 1 to 10 according to their potential earthquake hazard. Buffer zones of varying widths are to be generated around fault lines based upon their hazard ranking:

   Hazard Ranking    Desired Buffer Width (Meters)
     1                            0
   2,3,4                      2,500
   5,6,7                      5,000
   8,9                       12,000
    10                       20,000

The following figures show how a lookup table can be designed and used to create buffer zones of varying widths around each fault.

Note that when the Buffer tool does not find a matching value for the FAULTS.AAT HAZARD value, it will use the record with the next greater value. Therefore, the feature with HAZARD value of 3 is assigned a buffer distance of 2,500, and the features with HAZARD values of 5 and 6 are assigned a buffer distance of 5,000.


Geodatabase Lock Manager
Gedodatabase Lock Manager

Locks are placed on geodatabase feature classes when ArcToolbox, ArcCatalog or ArcMap accesses them. Locks are necessary to maintain data integrity since a feature class can be simultaneously read by many applications but only one application may write to a dataset at a time. Multiple users or applications updating a feature class at the same time may result in corrupted data.

If a dataset you want to use in a tool or wizard is locked, you will have to wait until the lock has been released by the user that applied the lock. Typically locking problems are caused when a tool requires a write lock for a feature class but another application has a read lock on the same dataset. A tool is unable to place a write lock on a feature class when someone else is has applied a read lock. Locks are applied to a coverage in the following situations:

A feature class is being previewed in ArcCatalog using the Preview tab. ArcToolbox will be able to use it, once the dataset is not being previewed.


Contour Wizard

Converts a grid or tin to a double precision line coverage.

The Contour Wizard produces engineering-quality contours, representing an exact interpretation of the Input surface model. Overall contour accuracy depends on how well the data used to create the grid or tin Input surface represents the actual surface.

The Contour Wizard runs the Arc LATTICECONTOUR command if the Input surface is a grid. It runs Arc TINCONTOUR if the Input surface is a tin.

Notes

Occasionally, engineering-quality contours may cross, appear to intersect or form an unclosed branching line. Crossing contours can occur in saddle regions that lie exactly on a contour interval. In other cases, the contours may pass so close to one another that they may appear to intersect. Branching contours can occur in cases of intersecting ridges that fall exactly on a contour interval. These are all valid engineering-quality interpretations of the surface that cartographers typically modify for aesthetic purposes.

The Contour Wizard applies special rules to the generation of contours through flat regions. Contours are never generated across flat regions. When a contour falls exactly at the same elevation as a flat region, the contour is drawn on the sides having higher neighboring regions. The trade-off of this solution is that the uppermost contour on a surface is not drawn if the contour falls exactly on a plateau formed by flat region.

The following illustrates where contours are drawn when a contour falls on the edges of flat regions:

When a contour falls exactly at the same elevation as a flat region, the contour is drawn on the sides with higher neighboring regions.

Notes for input grids

The output contours are limited to the minimum bounding rectangle containing all input grid mesh points; contours do not extend beyond the grid. Therefore, adjacent contour coverages should be edgematched, with the ArcEdit EDGEMATCH command, before using the Append Wizard to build a continuous contour coverage.

Contours are not generated through Input surface regions of NODATA.

Negative surface values may be interpolated to produce contours with negative values. In this case, the specified interval does not need to be a negative value.

The size of the mesh-point spacing affects contour appearance. Coarse grids often result in angular or blocky appearing contours.

With some datasets, the Contour Wizard can produce blocky looking contours. This occurs when the mesh point values are integers and they fall exactly on a contour, as a result of exact contouring of the data. There are three ways to overcome this condition if you would like smoother contours: smoothing the surface, adjusting the Base contour or both.

The smoothing approach involves slightly adjusting the mesh point z values so that a contour will no longer pass exactly through a mesh point. This can be done with the Arc FILTER command and a custom filter file such as the following:

.005  .005  .005.005  .960  .005.005  .005  .005

The accuracy of the contours will not be significantly affected, because the z-value adjustment is very small and heavily weighted in favor of the center mesh point.

Adjusting the Base contour involves offsetting the Base contour such that the contours no longer pass exactly through the mesh points. The offset can be very small; values as small as 0.0001 have been found effective.

Related Topics


Weed tolerance

Weed tolerance is the distance in ground units used to weed vertices along individual contour arcs. This value is compared to the trend line along each arc. Those contour vertices within the Weed tolerance distance of the trend line are dropped from the Output coverage. Contour nodes are always retained. The default Weed tolerance is 1/1000 of the minimum x or y extent of the input tin or grid extent.

The Contour Wizard uses the Douglas-Peucker algorithm to weed vertices along each contour. Trend lines are created beginning at a contour’s from-node to other vertices on the contour. The Weed tolerance is used to identify vertices to be weeded within the tolerance of each trend line.

If the specified Weed tolerance is too large, adjacent contours may intersect. If this invalid situation occurs, you should rerun the Contour Wizard with a smaller Weed tolerance.


Subdivision degrees

Subdivision degrees are available when the Input surface is a tin.

A subdivision degree of 1 (that is, no triangle subdivision) may produce angular appearing contours, especially when the triangles are large. More accurate and aesthetically pleasing contours can be generated by subdividing the tin triangles into sub-triangles. Increasing the triangular subdivision causes the triangulation to more closely conform to the smooth surface, resulting in smoother and more detailed contours than those derived without subdivision. It is also possible that more contours will be discovered using triangular subdivision.

The z values of the sub-triangle nodes are derived by break line bivariate quintic interpolation of the tin Input surface.

The Contour Wizard may ignore extremely narrow input tin triangles that would cause numerical precision errors if subdivided. Narrow triangles are typically present along a convex hull that has not been user defined by using a Clip polygon with the Create Tin Wizard. This can create minute discontinuities in a contour that are invisible to the eye, but cause a contour arc to be split into more than one arc. If this is unacceptable for your application, you may want to rebuild the tin with larger weeding and proximal tolerances or specify a lower subdivision degree.


Conversion Control Fle
Conversion control file

A structured file that lets you specify how to convert available feature classes and tables.


Table to Geodatabase

Converts INFO, dBASE, OLE DB or VPF tables to a geodatabase table and assigns them the ESRI Simple Row behavior class.

The tool checks the item names in the input table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings. You may also choose to not include certain columns from the input table in the new geodatabase table.

Duplicate table and feature class names are not permitted in a geodatabase. The tool will check for duplicate names once a geodatabase is selected. This process may take some time, depending on the size of the geodatabase you specify and whether you are using SDE or Access.

Only stand-alone INFO and dBASE tables are supported. Coverage feature class tables and shapefile dBASE tables will not convert.

Notes

Coverage and INFO table items are mapped based on a combination of their type and their width. For example, an item of type I can map to a short integer, long integer, or double, depending on its width. For detailed information on item to field type mapping between INFO and geodatabase, click here

Each different dBASE field type maps to a single geodatabase type independent of field size. The exception is the Number type field, which will map to a long integer if its number of decimals is zero and to a double if its number of decimals is greater than zero. For more detailed information on dBASE field type to geodatabase field type mapping click here

The name for an output table cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Related Topics


The name of the INFO, dBASE, OLE DB or VPF table you want to convert. Only stand-alone INFO and dBASE tables are supported. Coverage feature class tables and shapefile dBASE tables will not convert.


The name of the geodatabase that will contain the new table.


The name of the table to be created in the specified geodatabase.

The table name cannot begin with a numeric character.


The settings which will be used during the conversion. Click Change Settings to view or modify them.

Configuration keyword: References the database storage parameters on an SDE server. When loading data into an SDE geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Item names: Shows whether input item names have been modified or deleted. INFO and dBASE files allow characters in column names that other databases do not. The tool finds any illegal characters or reserved word field names in the input table, and corrects them for the output table.

Query: A SQL where clause that is used to create a selected set. Only the selected set will be converted to a table. If no expression is given, all rows will be converted.


Click to change Output settings.


Copy Items

Copies selected items to a new table. The tool automatically populates the Items list with items in the Input table. Click the View items button to see item definitions and values. Check Selected items only to see only the items you want to copy in the order in which they will appear in the Output table.

Notes

The tool copies up to 100 items as long as the total length of the item string does not exceed 256 characters.

A redefined item can be copied, but the items that it is redefined from are not copied unless you specify them. The redefined item becomes a regular item in the new table.

Alternate names of copied items are not maintained.

Related Topics


The table with items you want to copy.


The table you will create with the copied items.


Lists all items, including redefined items, in the Input table. Check the items you want to copy.


Moves a selected item up in the list. The items are stored in the Output table in the order shown here.


Moves a selected item down in the list. The items are stored in the Output table in the order shown here.


Choose which items to view.

Unchecked – displays all items.

Checked – displays only the items selected for copying.


Opens a window to view the Input table item definitions and values.


Coverage to Geodatabase Wizard

Converts a coverage to a Geodatabase dataset.

A new feature class is created for each coverage feature type in the dataset you choose in a selected Geodatabase. A dataset is your workspace in a Geodatabase, where you may have a number of feature classes sharing a common projection and fitting within a specified domain (coordinate extent).

Geodatabase Feature Classes

A Geodatabase Feature Class is a vector dataset that corresponds to a single type/collection of features such as Parcel, Lake or Transformer. A Feature Class consists of many features.

A Feature Class may be a member of a Feature Dataset or it may be stand-alone. A stand-alone Feature Class contains features that have no topological associations with features in other Feature Classes.

There is one type of geometry associated with the features in a Feature Class. The features in a simple Feature Class can have a geometry of type point, multipoint, polyline, or polygon.

Related Topics


Output feature dataset

To create a dataset in a new Geodatabase, first create the Geodatabase using ArcCatalog, or type the complete path and name of the new geodatabase in the Output Geodatabase feild.

When adding a coverage to an existing dataset, the projection information for both must match. If they differ, use the Project Wizard to project the coverage to the projection used in a dataset.

You must specify a database connection using the browser if you wish to add to a new or existing SDE dataset. You can create a new connection if one does not exist.

If you are adding a coverage to a new or existing OLE Database, you can use the browser to specify which connection and dataset to use, or you can give a path to the dataset in the input field. The path must include the database and the name of the dataset; for example, D:\test\usa\west, where ‘usa’ is the Geodatabase and ‘west’ is the dataset.

A domain is the coordinate extent of a dataset. No feature classes in the domain can have features that extend past these extents. If you are loading more than one coverage into a new dataset, load the one with the largest coordinate extent first so that the domain of the dataset is large enough to contain all of the coverage features you want.

In the geodatabase, annotation is not a geometry type, but a feature type. While coverage features are imported into feature classes that store ESRI simple features with geometry types of point, line, or polygon, annotation is stored in feature classes that store annotation feature types. If you import a coverage annotation feature class into the geodatabase using one of the data loading tools or wizards, these annotations are stored as simple line features, and their text and symbology are not converted. A different process exists for converting coverage annotation to the geodatabase. This process is described in Chapter 7, ‘Managing annotation’ of the Building a Geodatabase guidebook.

To view a summary of the mapping of coverage feature class type to geodatabase geometry type, click here

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.


Current spatial reference

When creating a stand alone feature class or creating a new feature dataset, the coordinate system and the domain extents will match that of the input data. Click Change… to alter the output coordinate system, and domain extent.

If the input and output coordinate systems are different, the features will automatically be projected. When adding a feature class to an existing feature dataset the coordinate system for the output feature class will automatically be set to match the coordinate system of the feature dataset.

Individual features with coordinates outside the X, Y and Z domain of the feature dataset will not be added to the output feature class. The M domain is excluded from this rule, feature with M values outside the M domain will still be added to the output feature class.

The coordinate range or domain extent of the output feature class is determined by the minimum coordinate, the maximum coordinate, and Precision values. Precision defines the scale of the dataset. The scale is the number of system units per one unit of measure. Therefore, this value specifies the degree of resolution. For example, in a projection system with meters as the unit of measurement, a precision value of 100 would be used to maintain centimeter-level resolution. Decreasing the Precision value increases the domain extent. Click Change… to alter the Precision value and the size of the domain extent.

Note: The default grid size value is in the units of the input projected coordinate system or geographic coordinate system. Changing the output coordinate system will require a new grid size, as it must be in the units of the output coordinate system. For example, if the input feature class has a geographic coordinate system and its units are decimal degrees, the default grid size may be 10. If the output coordinate system is set to be Lambert Conformal Conic with units in meters, the default grid size should be set to a value suitable for that new unit, such as 10000. If the default grid size is not updated, an error stating that the grid size is too small may occur or you may experience poor performance when working with the feature class as a result of an inappropriate grid size. If an error does occur, a new spatial index must be created for the feature class in ArcCatalog, before the feature class can be used.


New feature class names

The wizard assigns unique names to each Output feature class. You can change these names by first clicking on the name, then editing.

The wizard also assigns default values to the spatial index grid and the output item names for each feature class. If you want to view or edit the default values, change the Set options? value for a feature class by clicking on the 'No' and select 'Yes' from the drop down list. You will then be led to the Spatial index grid panel, then to the Item to field mapping panel.

Notes

The spatial index grid is used to boost spatial search performance and the item to field mapping of the attributes.

The wizard checks the item names in the input table for any characters or words that are illegal in the output table, and automatically changes them. The Item to field mapping grid is a summary of this conversion.


Spatial index

The spatial index is used to quickly locate features in a dataset that might match the criteria of a spatial search.  Careful creation of a spatial index will increase the efficiency of your spatial searches.  A poorly defined spatial index will increase the time needed to complete a spatial search.

Different indexing schemes are available depending on what relational database holds the geodatabase.

 Personal geodatabase, Oracle binary, SQL Server, DB2

 Oracle Spatial

 Informix


Item to field mapping

The wizard checks the item names in the input table for any characters or words that are illegal in the output table, and automatically changes them. The Item to field mapping grid is a summary of this conversion.

Original Fields shows the item names from the coverage feature attribute table, as well as required fields for the output, FID and Shape.

Original Error shows what problems occurred during the conversion.

Corrected Fields shows the item names that will be used in the output Geodatabase table, either the original name or the corrected name. You can edit this field if you want to change the default correction.

Delete field? always defaults to 'No'. If you want to delete a field from the dataset, change the setting by clicking on the grid value and selecting 'Yes' from the available drop down choices.

For example, the item FNODE# in an arc attribute table (AAT) cannot convert to an SDE dataset because the pound sign is not a valid character in an SDE field name. The Original Error will be 'Invalid character’, and the Corrected Fields value will be 'FNODE_'.

Coverage and INFO table items are mapped based on a combination of their type and width. For detailed information on item to field type mapping between coverages and the geodatabase, click here


Personal geodatabase, Oracle binary, SQLServer, DB2

If your geodatabase is a personal geodatabase, or is stored as Oracle binary, in a SQLServer, or DB2 database, the spatial index grid is a two-dimensional grid system that spans a layer. One to three 2-D grids (also referred to as grid levels), each with a distinct cell size, are created for a feature class. The first, or lowest, grid level has the smallest cell size.  Set the cell sizes of the other grids to 0 if you only want one, otherwise set each level at least three times larger than the previous level. Personal geodatabase feature classes have one grid level only.

By default, each of the data importing tools suggest a grid size for a two-dimensional grid system. This suggested grid size is based on the spatial reference, average feature size, and number of features in the input coverage. The suggested grid size is only an approximation. You can determine the optimum grid size for any feature class by examining the data and the needs of the application querying it.


Oracle spatial

If your geodatabase data is stored as Oracle Spatial, you have a choice of various index schemes. You can have no spatial index, an R-tree index, a Fixed Quadtree index or a Hybrid Quadtree index. Fixed indexing uses a linear quadtree index based on a tile size. Hybrid indexing uses both the fixed tile sizing and a variable sized tiling.

Whether a fixed or hybrid index is used, a tiling level is used to define the location of a geometry. Choosing the best tiling level for fixed indexing or the best number of tiles per geometry for hybrid indexing can impact performance. For more information on these indexing schemes, see Chapter 3, 'Oracle Spatial Geometry Type', and Chapter 4, 'Normalized Geometry Schema', in the ArcSDE Configuration and Tuning Guide for Oracle  PDF file, and Appendix A in the Oracle Spatial Users Guide and Reference.

The parameters required for these indexing schemes are as follows:

DBTune:
Grid level 1: 0
Grid level 2: 0
Grid level 3: 0

No index:
Grid level 1: -1
Grid level 2: ignored
Grid level 3: ignored

R-tree index:
Grid level 1: -2
Grid level 2: ignored
Grid level 3: ignored

Fixed quadtree index:
Grid level 1: -3
Grid level 2: <fixed tile size>
Grid level 3: ignored

Hybrid quadtree index:
Grid level 1: -4
Grid level 2: <fixed tile size>
Grid level 3: <number of tiles per geometry>


Informix

If your geodatabase is stored in an Informix database, the spatial index in an R-tree index. In this case, you do not have to provide any parameters for the grid levels. You can simply accept the defaults and click Next on the wizard.


Coverage to DFAD

Converts an entire workspace containing ArcInfo coverages to a single DFAD transfer file.

All coverages to be converted must:

Reside in the same workspace.

Have the same data structures as generated by DFAD to Coverage.

Be named with a common prefix in the format: DS<nnn>.

Have a DSnnn.DES file containing descriptive information about the data.

Supported file extension

Related Topics


The .DES file format

DATAFILE NAME: DSnnn.DES
COL ITEM NAME        WIDTH OUTPUT  TYPE  N.DEC
 1  IDENTIFIER          20    20     C
21  VALUE               30    30     C


The workspace with coverages you want to convert to DFAD format.


The DFAD file you will create.


Digital Feature Analysis Data (DFAD) is the National Imagery and Mapping Agency’s format for transfering weapons systems simulators. DFAD levels 1, 2, 1-C and 3-C are supported.


Coverage to DIME

Converts the arcs in a coverage containing line features to a Dual Independent Map Encoding (DIME) file in the standard U.S. Census Bureau, 300-character ASCII format.

The Input coverage must be in Geographic coordinates (latitude-longitude in decimal degrees) or State Plane coordinates (in feet).

For linear features, only the x, y coordinates of the from-node and to-node are written to the DIME file. Intermediate vertices defining a line's true shape are not transferred. Care should be taken to assure that this representation is reasonable for your intended application.

Notes

Standard DIME items in the coverage arc attribute table (AAT) are written to the DIME file. All items are optional and may be in any order. Some numeric items are transferred as characters.

About DIME files

Supported file extension

Related Topics


DIME files are digital versions of the Census Bureau’s Metropolitan Map Series, usually covering central city and adjacent populated areas of a Metropolitan Statistical Area. They include information for:

X,Y coordinates for street from- and to-nodes.

Street address ranges, and alternate ranges, with odd numbers on the left side; even on the right.

Non-street features such as railroads, streams and political boundaries.

Geographic codes such as census tracts and blocks.

Census tract numbers and block numbers to the left and right of each arc.

DIME files have since been replaced by TIGER files.


The coverage with arcs you want to convert to a DIME file. The coverage must have a defined projection of State Plane or Geographic.


The method for transferring the arc coordinates to the DIME file. The input coverage must have geographic coordinates or be projected to the State Plane reference system. The input Coordinate field is automatically determined and displayed using the coverage’s defined projection parameters.

Geographic – The tool will write coordinates to the latitude-longitude field (in decimal degrees).

State Plane – The tool will write coordinates to the State Plane coordinate field (in feet).


The DIME file you will create.


About DIME files

The GBF/DIME file is a digital version of the Census Bureau’s Metropolitan Map Series with address ranges, geographic codes (such as census tracts and blocks), and x,y coordinate values at nodes.

Each record in the GBF/DIME file identifies a street segment (as a two-point line) on the map by its nodes (e.g., From-node 20, To-node 21). Address ranges are given for the left and right sides of the arc (e.g., odd numbers 101  199 on the left side and even numbers 100  198 on the right side). Census tract numbers, block numbers, and other polygonal data are also recorded for the left and right polygons of each arc.

A DIME file usually covers the central city and contiguous populated areas of a Metropolitan Statistical Area. It includes records for streets and selected non-street features (such as railroads, streams and political boundaries). It also includes alternate address records, indicated by an NS.CODE field equal to 9. The Dime to Coverage tool is used to convert this information into an ArcInfo coverage.

The GBF/DIME data model requires that arcs have only two coordinate pairs (i.e., that an arc has only nodes and no other vertices). Coverage to DIME conforms to this standard, and writes only the first and last coordinate pairs of each coverage arc. Care should be taken to assure that this representation of a coverage will prove reasonable.


Coverage to DIME searches for the AAT items listed in the table below, and uses them as the source for attribute data to be added to the output GBF/DIME file. All items are optional and may be in any order. (These are the same items produced by the DIME to Coverage tool for the ACODE file.)

ITEM NAME         WIDTH OPUT TYP N.DEC
PRE.DIR               2    2  C    -
STREET.NAME          20   20  C    -
STREET.TYPE           4    4  C    -
SUF.DIR               2    2  C    -
NS.CODE               1    1  C    -
L-ED                  6    6  C    -
R-ED                  6    6  C    -
FILLER1               4    4  C    -
F-MAP.BASIC           3    3  I    -
F-MAP.SUF             2    2  C    -
T-MAP.BASIC           3    3  I    -
T-MAP.SUF             2    2  C    -
CODING.LIMIT          1    1  C    -
L-F-ADD               6    6  I    -
L-T-ADD               6    6  I    -
R-F-ADD               6    6  I    -
R-T-ADD               6    6  I    -
FILE.CODE             4    4  I    -
CENSUS.ID             6    6  I    -
CHECK.DIGIT           1    1  I    -
L-TRACT.BASIC         4    4  I    -
L-TRACT.SUF           2    2  I    -
R-TRACT.BASIC         4    4  I    -
R-TRACT.SUF           2    2  I    -
L-ZIP                 5    5  I    -
R-ZIP                 5    5  I    -
SMSA                  4    4  I    -
FILLER2               5    5  C    -
F-NODE                4    4  I    -
T-NODE                4    4  I    -
L-PLACE               4    4  I    -
R-PLACE               4    4  I    -
L-STATE               2    2  I    -
L-COUNTY              3    3  I    -
L-MCD                 3    3  I    -
FILLER3               5    5  C    -
L-BLOCK               3    3  I    -
FILLER4               3    3  C    -
R-STATE               2    2  I    -
R-COUNTY              3    3  I    -
R-MCD                 3    3  I    -
FILLER5               5    5  C    -
R-BLOCK               3    3  I    -
FILLER6               3    3  C    -
F-SP.ZONE             2    2  C    -
T-SP.ZONE             2    2  C    -
FILLER7              24   24  C    -
F-LATITUDE            6    6  I    -
F-LONGITUDE           7    7  I    -
T-LATITUDE            6    6  I    -
T-LONGITUDE           7    7  I    -
F-SPY                 7    7  I    -
F-SPX                 7    7  I    -
T-SPY                 7    7  I    -
T-SPX                 7    7  I    -
FILLER8              42   42  C    -

**  REDEFINED ITEMS  **
L-TRACT               6    6  C    -
R-TRACT               6    6  C    -
F-MAP                 5    5  C    -
T-MAP                 5    5  C    -

For a discussion of GBF/DIME limitations and special considerations, refer to additional information that may be obtained directly from the Census Bureau.


Coverage to DLG

Creates a Digital Line Graph (DLG) Optional format file from ArcInfo coverages.

Conversion example

Recommended pre-processing

To sequentially number all nodes in the Input coverage, use the Renumber Nodes tool. This will ensure that all arc, node and polygon feature internal numbers are sequential.

Notes

There are two distribution formats for a DLG file, Standard and Optional. The tool writes a DLG in the Optional format only.

To create a DLG file which contains only point features, you should specify an Input coverage which contains one rectangular polygon defining the area covered by the points. Use the name of the point coverage for the Point coverage option.

Only one DLG category or layer can be saved in a DLG file created by Coverage to DLG. A DLG category is equivalent to a layer in a map.

Output DLG files

Coverage attributes used in the conversion

How coverage coordinates are used

Header files

Header file keywords and descriptions

Supported file extension

Related Topics


The coverage you want to convert to DLG format.


Controls whether or not a coordinate transformation is performed. When transformed, all coordinates are translated using the same affine transformation equation. This ensures that the accuracy of coordinates is preserved in the new DLG file.


The coverage with points that you want to include in the DLG file.


The file with coverage projection information that you want to include in the DLG file’s header.


The file with additional coverage information that you want to include in the DLG file’s header. If it does not already exist, you can create it by clicking the adjacent browser button and then clicking ‘Yes’ to start the Header and Control File Builder.


A constant value that will be added to all coverage x-coordinates to preserve their accuracy. This applies especially to a single precision coverage in UTM with y-coordinates in the 3 to 6 million range.


A constant value that will be added to all coverage y-coordinates to preserve their accuracy. This applies especially to a single precision coverage in UTM with y-coordinates in the 3 to 6 million range.


The DLG file you will create. Its format type is always Optional.


Output DLG files

The internal feature numbers (Cover#) are written as the output DLG feature numbers.

Coverage topology is saved in the DLG file using conventions which are similar to the way topology is stored in a coverage (e.g., polygons are defined in clockwise loops, islands as counterclockwise loops, each feature has a unique identification number, negative numbers for lines indicate reverse directions, and so on).

For each Input coverage polygon: the polygon’s internal number, its label point location (x,y), the list of arcs which define it, and any major/minor attribute pairs are all saved in an Area (A) record in the output DLG.

For each Input coverage arc: the internal number of the arc, its from-node and to-node numbers, its coordinates, its left and right polygon numbers, the set of x,y coordinates which define the line, and any major/minor attribute pairs are all saved in a Line (L) record in the output DLG.

For each Input coverage node: the internal number of the node, its (x,y) location, a list of arcs beginning or terminating at the node and any major/minor attribute pairs are all saved in a Node (N) record in the output DLG.

For each Point coverage point feature: its x,y location and any major/minor attribute pairs are saved in a zero-length Line (L) record. These are referred to as degenerate lines in a DLG. The feature numbers for points will be sequential and will be offset from the last Line (L) record written to the file. A Node (N) record without the attribute information will also be created for each degenerate Line record (in accordance with the DLG format specification).


Coverage attributes used in the conversion

Coverage To DLG looks for major/minor attribute pairs for lines, polygons and node features in Input coverage and for points features in Point coverage.

MAJOR1    MINOR1
MAJOR2    MINOR2
:                   :
MAJORn    MINORn

Coverage To DLG first looks for these items in the feature attribute tables created by the DLG to Coverage tool.  If these files do not exist, then the appropriate CODE tables will be searched.

Input	Attribute 	CODE	Major/Minor Attribute Pairs

Table	Table

Input	AAT 	ACODE 	ARC attributes written to Line (L) records in

coverage	DLG file

Input	PAT	PCODE	POLY attributes written to Area (A) records

coverage 	in DLG file

Input	NAT	(none)	NODE attributes written to Node (N) records

coverage 	in DLG file

Point coverage	PAT	XCODE	POINT attributes written to Line (L) records

in DLG file


How coverage coordinates are used

When Transform Coordinates is checked, the x,y coordinates for both the header file’s control points and the coverage features are automatically scaled to fit the DLG coordinate record format, using the same affine transformation equation. This transformation ensures that the accuracy of coordinates is preserved. When Transform Coordinates is unchecked, no coordinates are translated

DLG attributes are always integer pairs containing one to six digits. Items must be paired and defined as numeric items. Real numbers are truncated when written to the DLG. Since 0 is assumed to be a valid attribute value, -99999 can be used to signify Nodata. If -99999 is encountered for a Major-code or Minor-code item, then the attribute values are blank in the output DLG, not -99999.

Coverage coordinates are not projected by Coverage to DLG. The projection parameters, used only to describe the projection system of the coverage coordinates, are saved in the output DLG header records.

The Projection file should be in the same format as required by the Project Wizard and Define Projection Wizard. Projection information will be taken first from the Projection file, then from the Input coverage’s projection definition file.

You can use the Define Projection Wizard to define projection parameters for the Input coverage. If the coverage projection has not been defined and the Projection file option is not used, then no projection information will be written to the output DLG file.

Quite often, a constant value is subtracted from coverage coordinates, especially y-coordinate values in the 3 to 6 million range (UTM). This is done to preserve accuracy for single-precision coverages. This value is referred to as an x-shift or y-shift and should be added back onto the coordinates when they are written out to the DLG file. You can specify x and y-shift values several different ways. The following is the order of precedence that Coverage to DLG uses when determining which values to use.

1. X shift and Y shift options on the tool.

2. Xshift and Yshift parameters in the Projection file.

3. Xshift and Yshift parameters in the Input coverage (PRJ) file4. Default value is zero, if not found in any of the above.

The x and y-shift values are automatically applied to both the header file control points and the feature coordinates written to the DLG file.


Header files

Header information files are created with your system’s text editor or the Header and Control File Builder. The file may contain any or all of the keywords listed in Header file keywords and descriptions.

The default value is used for each keyword when that keyword is not included in the header file. The order of the keywords in the file is not important.

An illustration of a header file is shown in the example section.

Tics in the Input coverage are not written to the DLG file. In order to preserve tic locations, use the In Header file option and specify the x,y locations for tics as CONTROLPOINTs in the header file.

If CONTROLPOINTs are not specified in the header file, Coverage to DLG will use the BND information of the coverage to write values to the header of the DLG file.


Header file keywords and descriptions

TEXT {string} - written to the third DLG record; up to 41 alphanumeric characters. The default is blank.

MAPNAME {string} - written to the second DLG record; up to 40 alphanumeric characters. The default is blank.

CATEGORY {string} - name of data category or layer; up to 20 alphanumeric characters. The default is coverage name.

SOURCEDATE {date}{revision_date} {revision_code} - source date, revision date and revision code, if any. Dates entered as YYYY. Code is: P - photo revision, I  - photo  inspection, D - digital revision. The default is today’s date and no revision code.

RESOLUTION {factor} - data resolution, the default is 1.0 (real value).

SCALE {denominator} - map scale, the default is 0 (integer value).

CONTROLPOINT {SW|NW|NE|SE}{lat}{long}{x}{y} - list of four control points with latitude and longitude and corresponding x,y locations of each control point. The latitude and longitude coordinates are in Decimal Degrees; x,y coordinates are in coverage units. Any X shift, Y shift or transformation values used will also be applied to the control point x,y coordinates before they are written to the DLG file by Coverage to DLG. The defaults are 0.0 in each field.

SECTIONINDICATOR {indicator_sequence} - code S, F, or T for the size of the section followed by the sequence number.

LARGESTCONTOUR {interval_unit} - largest primary contour interval followed by the interval unit (1 = feet, 2 = meters). Present only if two or more primary intervals exist.

LARGESTBATHYMETRIC {interval_unit} - largest primary bathymetric contour interval followed by the interval unit (1 = feet, 2 = meters, 3 = fathoms). Present only if two or more primary intervals exist.

SMALLESTCONTOUR {interval_unit} - smallest or only primary contour interval followed by the interval unit (1 = feet, 2 = meters).

SMALLESTBATHYMETRIC {interval_unit} - smallest or only primary bathymetric contour interval followed by the interval unit (1 = feet, 2 = meters, 3 = fathoms).

HORIZONTALDATUM {datum} - Horizontal Datum of DLG.

0 or blank = NAD 27 (default)
1 = NAD 83
2 = Puerto Rico
3 = Old Hawaiian
4 = Local (Astro)
5 = Guam

VERTICALDATUM {datum} - Vertical Datum of DLG. Zero or blank = NGVD 29 (default), 1 = NAVD 88, 2 = Local Mean Sea Level.

DLGCENTER {long}{lat} - the longitude and latitude of the zone center point in DMS.


Conversion example

In this example, a coverage named D1COV is converted to a DLG. The coverage projection information defined for this coverage will be used to add projection parameters to the DLG header records. Coverage coordinates are not projected by the tool. The projection parameters only describe the projection system of the coverage coordinates.

The DLG format (Appendix 2-D of the USGS Standards for DLG) requires that for coordinate systems that normally have zone numbers, the header section of the DLG must contain both the zone number and the latitude-longitude values for the zone point or the center of the data.

The zone may be specified as a ZONE number in the INPUT section of the projection definition file or as latitude-longitude values for the center of the data in the PARAMETERS section but the projection file does not support both. To write a DLG that contains both, specify zone number in your projection file and zone point using DLGCENTER keyword in your header file .

The following is the information in the coverage projection file:

Coordinate System Description

Projection	UTM
Zone	13
Units	METERS
Datum	NAD27
Spheroid	CLARKE1866
Xshift	0.0000000000
Yshift 	0.0000000000
Parameters

The following header information file named HEADER.FIL will be used to create the appropriate information in the output DLG.

HEADER.FIL

MAPNAME DURANGO, CO

CATEGORY HYDROGRAPHY

SOURCEDATE 1995

RESOLUTION 2.54

SCALE 100000

SECTIONINDICATOR F02

LARGESTCONTOUR 5002

VERTICALDATUM 1

CONTROLPOINT SW   37.250000 -107.750000 256087.53  4125947.50

CONTROLPOINT NW   37.500000 -107.750000 256898.08  4153690.33

CONTROLPOINT NE   37.500000 -107.500000 279000.18  4153071.89

CONTROLPOINT SE   37.250000 -107.500000 278265.94  4125332.02

DLGCENTER -107 37 30  37 22 30

The following lists part of EXAMPLE.DLG, the output DLG file from the tool using the above projection and header files. No transformation was specified.

ESRI    DLG DATA - CHARACTER FORMAT - 05-08-92 VERSIONDURANGO, CO                              1995         100000   F02                                     5002,         3     1    13     2 0.25400000000D+01     4     0     4     1  0  0  -0.107037030000000D+09   0.370220300000000D+08   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00 0.10000000000D+01 0.00000000000D+00 0.00000000000D+00 0.00000000000D+00SW       37.250000 -107.750000         256087.53  4125947.50NW       37.500000 -107.750000         256898.08  4153690.33NE       37.500000 -107.500000         279000.18  4153071.89SE       37.250000 -107.500000         278265.94  4125332.02HYDROGRAPHY            0   135   135 010     0     0 010   157   157   1


Coverage to DXF

Converts ArcInfo coverages into an AutoCAD Drawing Interchange File (DXF).

Notes

At least one input coverage must be specified.

All annotations for all subclasses in Input anno coverage will be written to the output DXF file. Annotation strings are output as Text entities. Each level of annotation is written as a unique DXF layer. The layer name is the annotation level number followed by the annotation coverage name (e.g., 3ROADS for annotation level 3 from the coverage named ROADS).

The names specified for Input line coverage, Input point coverage and Input anno coverage will be used as layer names in the DXF file when no layer name is specified in the DXF-LAYER INFO item. AutoCAD accepts single-word names as layer names with no extensions and no internal periods

Arcs are output as Polyline, Circle, or Arc entities, depending on the value of the INFO item DXF-CURVE found in <Input line coverage>.ACODE. If this item does not exist, all arcs will be output as Polylines.

The resulting DXF file will be 10 to 20 percent larger than the coverage from which it was generated.

The Block name, taken from item DXF-ATTRIB for Insert entities, will be used to generate dummy Block definitions in the DXF file. AutoCAD requires that Blocks referenced by Insert entities be defined separately. The dummy Blocks section written to the DXF file will not contain drawing elements.

The header records, containing default tables and header information, are located at the beginning of the Output DXF file.

Converting polygon coverages

Defining the minimum and maximum x,y extents and units of precision

Coverage attributes used in the conversion

Summary table for point to DXF conversion

Supported file extension

Related Topics


Coverage attributes used in the conversion

Attribute information for lines and points is taken from standard DXF items in the Input line coverage and Input point coverage. These are the same standard DXF items created by the DXF to Coverage Wizard. These items can also be alternate or redefined item names and are read from the ACODE and/or XCODE files if no standard DXF items exist in the AAT and/or PAT files.

The ACODE and XCODE INFO files are created by the DXF to Coverage Wizard. The ACODE file relates to the AAT and the XCODE relates to the PAT. If the coverage was not created by the DXF to Coverage Wizard, you may create these related tables.

Line attributes

Standard DXF items for the Input line coverage are:

DXF-LAYER             31    31     C      -
DXF-COLOR              3     3     I      -
DXF-THICKNESS          4    12     F      3
DXF-TYPE              10    10     C      -
DXF-ELEVATION          4    12     F      3
DXF-HANDLE            16    16     C      -
DXF-CURVE              1     1     I      -

DXF-LAYER - character item which specifies the layer name to which the entity belongs. The default value will be the input coverage name if no DXF-LAYER item or item value for the feature is found.

DXF-COLOR - numeric item containing the DXF color of each entity. If item value is zero or item does not exist, then no value will be written to the DXF file.

DXF-THICKNESS - numeric item whose value is the thickness of the entity. If item value is zero or item does not exist, then no value will be written to the DXF file.

DXF-TYPE - character item that describes the line type. Acceptable character strings include CONTINUOUS and DASHED. If item value is blank or item does not exist, then no value will be written to the DXF file.

DXF-ELEVATION - numeric item whose value represents the elevation for the entire entity. If item value is blank or item does not exist, then no value will be written to the DXF file.

DXF-HANDLE - character item whose contents will be written to the DXF file but will not necessarily be preserved when AutoCAD retrieves the file. Entity handles are maintained internally in AutoCAD and while the DXF to Coverage Wizard can preserve the hex value of the original DXF element, AutoCAD may overwrite it. It is similar in function as ARC/INFO's COVER#.

DXF-CURVE - indicates whether the line feature is a curve (1) or a line (0).  If it is set to 1, then a Circle or Arc entity will be written. The first, middle and last points of the line feature are used to compute the curve.  Arcs with a DXF-CURVE value of zero, including 2-point arcs will be written as Polyline entities, which is the default.

Point attributes

Standard DXF items for the Input point coverage include:

DXF-LAYER             31    31     C      -
DXF-COLOR              3     3     I      -
DXF-THICKNESS          4    12     F      3
DXF-TYPE              10    10     C      -
DXF-ELEVATION          4    12     F      3
DXF-HANDLE            16    16     C      -
DXF-ANGLE              4    12     F      3
DXF-SIZE               4    12     F      3
DXF-TEXT              xx    xx     C      -
DXF-ATTRIB            xx    xx     C      -
DXF-IID                4     5     B      -

DXF-LAYER - character item which specifies the layer name to which the entity belongs. The default value will be the input coverage name if no DXF-LAYER item or item value for the feature is found.

DXF-COLOR - numeric item containing the DXF color of each entity. If item value is zero or item does not exist, then no value will be written to the DXF file.

DXF-THICKNESS - numeric item whose value is the thickness of the entity. If item value is zero or item does not exist, then no value will be written to the DXF file.

DXF-TYPE - character item that stores style name for Text and Attribute entities. Item must be blank for Points, Shapes and Inserts.  The default text style is STANDARD for Text and Attributes.

DXF-ELEVATION - numeric item whose value represents elevation for the entity. If item value is zero or item does not exist, then no value will be written to the DXF file.

DXF-HANDLE - character item whose contents will be written to the DXF file but will not necessarily be preserved when AutoCAD retrieves the file. Entity handles are maintained internally in AutoCAD and while the DXF to Coverage Wizard can preserve the hex value of the original DXF element, AutoCAD may overwrite it. It is similar in function as ARC/INFO's COVER#.

DXF-ANGLE - numeric item whose value is the angle of rotation for the entity specified in decimal degrees.  Default value is 0.0.

DXF-SIZE - numeric item that stores the value for Text and Attribute height, Shape size, or scale factor for Insert entities. The default size is 0.2 inches.

DXF-TEXT - character item that stores Text strings or Attribute values. Must be blank for Point, Shapes and Insert entities.

DXF-ATTRIB - character item that stores item name of Attribute, name of Shape, or name of Block referenced by Insert.  Must be blank for Point and Text entities.

DXF-IID - stores Insert ID number to uniquely identify each insert and to identify the Attributes that belong to them. Attributes should have the same IID value as the Insert they belong to. Must be zero for Points, Text and Shape entities.


Summary table for point to DXF conversion

Point features are output as Point, Text, Shape, Insert, or Attribute entities depending on the presence or absence of certain DXF item values in <Input point coverage>.XCODE. The following DXF attributes and values must be present in the PAT or XCODE to convert a point to the indicated DXF entity types:

To convert a point to the DXF entity type:

DXF item	Point	Text	Shape	Insert	Attribute item
DXF-text	blank	text string	blank	blank	attribute value
DXF-attribute	blank	blank	shape name	block name	attribute name
DXF-type	blank	text style	blank	blank	text style
DXF-iid	zero	zero	zero	insert ID	insert ID

All other DXF items that are present in the point attribute table should have a value of zero or blank, depending on their data type, with the exception of DXF-LAYER.

If other DXF items are present in the point attribute table, and the values need to be maintained, use the Copy Items tool to extract all of the extra DXF items, along with the <Input point coverage>-ID, into a new INFO table. This new table could be given the XCODE extension if the <Input point coverage>.XCODE file does not already exist.

This new table can then be associated to the point attribute table using the <Input point coverage>-ID in a relate or by using the Join tables tool after the Coverage to DXF tool is used. If the <Input point coverage>.XCODE does exist, create a relate and update the XCODE’s DXF item values before changing the values in the point attribute table.

Extra DXF item values that are maintained in the <Input point coverage>.XCODE do not affect the Coverage to DXF tool's Point Summary Table usage if the DXF item is also maintained in the point attribute table. If the DXF item values need to be maintained in the XCODE file, add the necessary DXF items to the coverage's point attribute table, create a relate and move the appropriate values from the XCODE DXF items.


The line coverage you want to convert to DXF format. You may convert only this coverage, or convert it together with a point and/or annotation coverage.


The point coverage you want to convert to DXF format. You may convert only this coverage, or convert it together with a line and/or annotation coverage.


The annotation coverage you want to convert to DXF format. You may convert only this coverage, or convert it together with a line and/or point coverage.


Select the number of decimal places you want to store the coordinates and other numeric data in the DXF file. The value range is 0 to 16. We recommend 2.


The DXF file you will create.


Choose the file format of the new DXF file.

ASCII – It is the default format for this tool and AutoCAD. ASCII files are readable in a text editor and have fewer problems when transferred over a network, making them easier to work with if problems occur. A disadvantage is the larger file size.

Binary - Binary files are typically 25% smaller than ASCII files and can be written and read much faster. They are not readable in a text editor so you are unable to fix transfer errors if they occur. Binary files conform to the AutoCAD 11 standard.


Converting polygon coverages

To convert the arcs of a polygon coverage, first create an arc attribute table (AAT) using the Build tool with the Feature class set to Line. Then specify the polygon coverage name as the Input line coverage. Label points can be converted by specifying the same polygon coverage as the Input point coverage.


Minimum and maximum x,y extents and units of precision

Three variables that define the minimum and maximum x,y extents of the graphic features and the units of precision for coordinates and distances are also written to the DXF file.

$EXTMIN - x,y drawing extent of the lower-left corner.

$EXTMAX - x,y drawing extent of the upper-right corner.

$LUPREC - units of precision for coordinates and distances.


Export to Interchange File

Converts a coverage, grid, tin or INFO table to an interchange file for transfer to another platform.

Notes

When exporting a coverage, all associated INFO tables are written to the interchange file. For example, if the coverage name specified for Input data is FOREST, an INFO table named FOREST.LABEL would be saved in the interchange file. A table named FOREST1.LABEL, however, would not be saved in the interchange file.

Export files created with the Compression option set to Full, can be significantly smaller than export files created with the Partial or None options.

Exporting a grid can result in an export file much larger than the original grid, even when Full compression is used. This is because each grid cell must be represented in the export file in ASCII format, which is less efficient than the grid's binary format. Also, integer grids are stored in a compressed format, which cannot be maintained in the export file.

The best solution is not to export large grids. All ArcInfo platforms that support grids now read the same file format, so exporting is not necessary. To create a single file for transfer, a utility such as PKZIP (or 'tar' on UNIX systems) can be used to place the workspace containing the grid into a single file. Versions of PKZIP and tar are available on both UNIX and PC systems. Warning: Do not PKZIP or tar just the grid, because you will lose the INFO tables. If you don't want to transfer all the grids in your workspace, create a temporary workspace and copy the grids to be transferred into it.

Coverages to be exported should not contain edit masks. In other words, do not export an uncleaned cover. Run the Build or Clean tools to remove edit masks (msk.adf file in the coverage directory.)

Export has a limit of -999999999 on negative User-IDs.

Checklist of issues when exporting

Different versions of ArcInfo

Related Topics


Checklist of issues when exporting

The following is a checklist of issues one should be concerned about when taking an export file from one platform to another.

Run Export to Interchange File with the None option. This creates non-compressed ASCII files that are easier to handle than fully or partially compressed ASCII files. Fully or partially compressed ASCII files can cause problems when transferring data across different platforms, such as UNIX ArcInfo to PC ArcInfo and vice versa.

Always import the interchange file back to the host platform to make sure the ‘.E00’ file is error free. Export to Interchange File does not check for errors within the input dataset, but the import tool does check the interchange file. If changes need to be made, they must be made to the input dataset, not to the ‘.E00’ file.

If you are transferring data from UNIX or NT ArcInfo to PC ArcInfo, make sure the exported data is in single precision. Use the Arc COPY command with the {SINGLE} option to convert your dataset to single precision prior to running Export to Interchange File. Note that PC ArcInfo Rev 3.4.2D or higher will accept double precision export files and convert them to single precision for use.

Use the Max. lines option to create more than one volume for the export file. A value of 20,000 will create volumes that are able to fit onto a high density floppy disk. Use a finite number so that at least two volumes are created. Transfer both files to the other platform and make sure that they are in the same directory, because the import tool automatically searches for the next volume when more than one volume is created.

If any numeric (N type) items exist, make sure they have one or more decimal places. In ArcCatalog, you can alter the item definition to change items with 0 decimal places.

If there is a character (C type) item, make sure that there is a value in it; do not leave it blank. Place any character, or characters, in any empty records, such as ‘x’ or ‘undefined’.

If there is a binary (B type) item, make sure the internal width is either 2 or 4.

If there are any floating (F type) items, make sure that the internal width is either 4 or 8. Other settings are not recognized by ArcInfo.

For integer (I type) items, the maximum width is 16 and the range is +/- 2, 147,483,647.

Make sure the <cover>-ID (also referred to as the User-ID) values are unique in all feature attribute tables (FAT’s) if transferring a coverage from UNIX or NT ArcInfo to PC ArcInfo. The <cover>-ID item is used for all links to additional user attribute items in PC ArcInfo, while the <cover># item is used in UNIX and NT ArcInfo. Run ‘CALC <cover>-ID = <cover>#’ in INFO, if the <cover>-ID was set to a non-unique set, for the arc and point attribute tables. For the polygon attribute table use ‘CALC <cover>-ID = <cover># - 1’, as the universe polygon must be 0. Then run the Update IDs tool, followed by the Export to Interchange File tool.

When transferring export files between UNIX and PC platforms, make sure the ASCII interchange file is in the proper format. UNIX systems have tools like 'dos2unix' and 'unix2dos' to convert DOS ASCII files to UNIX ASCII files and vice versa. PC ArcInfo Rev 3.4.2, has the ‘unix2dos’ and ‘dos2unix’ commands as well. In general, if FTP is used for file transfer, this conversion is done automatically. However, it never hurts to make sure. If the ‘.E00’ file is in DOS format, it will have ^M characters when viewed on a UNIX platform.


Different versions of ArcInfo

Problems may occur when importing onto platforms running earlier versions of ArcInfo. The export file may contain a dataset that is not available in earlier versions, or the format of an existing dataset may no longer be compatible with earlier versions. Also there are cases where the export file will import correctly but the output cannot be used the same way.

There is no problem transferring to a later version of ArcInfo. All export interchange files are upwardly compatible.

Coverage index files and anything in double precision cannot be imported to pre-5.0 versions of ArcInfo.

Node attribute tables, routes, sections and annotation subclasses will import into versions prior to Rev 6.0 as associated INFO data files for the output coverage, but will not function the same way they do at Rev 6.0 or later.

Region subclasses (PATsubclass files) will import into versions prior to Version 7 as associated INFO data files for the output coverage. Region subclass PAL and RXP files will not be imported. The region feature class was not supported prior to Version 7.

You cannot export a 6.0 tin to another platform running an earlier version. Beginning with TIN 6.0, the x,y coordinates for the tin nodes are stored in double precision. The Rev 6.0 tin data model supports break lines and nonconvex hulls. These enhancements are not supported in earlier releases.

ADD files can be imported but must be rebuilt using the Arc command ADDRESSBUILD.


The geodataset or file you want to export.


The Dataset type is automatically determined from the specified Input data. The valid types for this tool are:

Coverage – exports a coverage and all INFO tables and index files that have the same name.

Grid – exports an integer or floating point grid. NOTE: Interchange files for grids tend to be larger than the grid itself because of ASCII encoding. We recommend that you use a compression program, such as PKZIP (NT) or the TAR command (UNIX), to transfer a grid and its INFO tables.

INFO – exports an INFO table.

Tin – exports a tin.


Choose the type of compression for the Output file.

None – no compression is performed. Uncompressed files transfer more easily between platforms. Line length is up to 80 characters.

Partial – compresses blanks; does not compress numbers.

Full – compresses blanks and numbers.


Lets you limit the size of the interchange files. A value of 20,000 creates a file that will fit on a 3.5 HD floppy disk. A finite number creates at least two interchange files. If you do not specify Max. lines, only one interchange file is created.


The interchange file you will create. It will have the extension .E00.

Additional interchange files, with extensions of .E01, .E02, .E03 to .E99, are created when the maximum number of lines you have specified for each file is reached.


Coverage to Geodatabase

Converts a feature class stored in a coverage to a new feature class in a Geodatabase and assigns it the ESRI Simple Feature behavior class.

When you import coverages, you create a new standalone feature class, a new feature dataset and feature class, or a feature class in an existing feature dataset. In the first two cases, you have to define a spatial reference.

If your coverage has a defined projection, the tool will automatically create the new feature class with the same projection, unless you specify otherwise. If you do choose to import the data into a different projection than the source data is in, the features will automatically be projected.

Because all feature classes in a feature dataset share the same spatial reference, you must only specify a new spatial reference when loading the first feature class or when creating the feature dataset in ArcCatalog.

When expanding the feature dataset to include additional feature classes, remember that all features in all feature classes must have the same coordinate domain extent. This includes the x, y, z values and the precision. Feature classes in the same feature dataset can have different M values.

A suggested grid size is given based on the spatial reference, average feature size, and number of features in the input coverage. The suggested grid size is only an approximation. You can determine the optimum grid size for any feature class by examining the data and the needs of the application querying it.

When you convert data from one format to another, a question arises about how data of a specific type maps from one format to the other. Importing data into the geodatabase is no exception. In this case, how both the spatial type and the attribute field type map from one data type to another must be considered. For each geodatabase field type, the field itself is persistently stored in the database differently depending on which RDBMS stores the geodatabase.

All feature class types and attribute item types in coverages are mapped to geometry and field types in the geodatabase. More than one feature class type in a coverage will map to the same geometry type in the geodatabase. For example, points, tics, and nodes all map to geometry type point.

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings…. You may also choose to not include certain columns from the input table in the new Geodatabase table.

Notes

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the Geodatabase you specify and whether you are using SDE or Access.

In the geodatabase, annotation is not a geometry type, but a feature type. While coverage features are imported into feature classes that store ESRI simple features with geometry types of point, line, or polygon, annotation is stored in feature classes that store annotation feature types. If you import a coverage annotation feature class into the geodatabase using one of the data loading tools or wizards, these annotations are stored as simple line features, and their text and symbology are not converted. A different process exists for converting coverage annotation to the geodatabase. This process is described in Chapter 7, ‘Managing annotation’ of the Building a Geodatabase guidebook.

To view a summary of the mapping of coverage feature class type to geodatabase geometry type, click here

Coverage and INFO table items are mapped based on a combination of their type and width. For example, an item of type I can map to a short integer, long integer, or double, depending on its width. For detailed information on item to field type mapping between coverages and the geodatabase, click here

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Spatial Reference and Domain extents

Spatial index grid

Related Topics


The name of the coverage to be converted to a Geodatabase feature class.


The coverage feature class you want to convert.


The name of the Geodatabase that will contain the dataset with the new feature class.


The name of a new or existing dataset that will contain the new feature class in the specified Geodatabase.


The name of the feature class to be created.

The feature class name cannot begin with a numeric character.


The settings that will be used during the conversion. Click the Change Settings… button to modify them.

Spatial reference: The output coordinate system determined from the input coverage feature class. The projection will be copied from the coverage, and the spatial domain calculated.

Grid size: The spatial index grid is a two-dimensional grid system that spans a layer, like the locator grid you might find on a common road map. It is used to quickly locate features in a dataset that might match the criteria of a spatial search.

Item names: Shows whether input item names have been modified or deleted. INFO  files allow characters in column names that other databases do not. The tool finds any illegal characters or reserved word field names in the input table, and corrects them for the output table.

Query: A SQL where clause that is used to create a selected set. Only the selected set will be converted to a feature class. If no expression is given, all features will be converted.

Keyword: A keyword that references database storage parameters on an SDE server. When loading data into an SDE Geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Geometry: M and Z values must be created at the same time as a feature class or feature dataset is created, as they can not be subsequently added. If the Enable M values on the output is checked the output feature class will have linear measurement (M) values. If you do not want your new feature class and/or feature dataset to contain M values, uncheck this option.


Click to modify the Output settings.


Coverage feature class to geodatabase geometry type mapping

Coverage feature class	Geodatabase geometry

point	point

arc	line (polyline)

polygon	polygon

node	point

tic	point

region	polygon

route	line (polyline) with measures

annotation	annotation*

*Annotation in the geodatabase is not a geometry type, but is implemented as a feature type.


Coverage, INFO item to geodatabase field mapping

Item type	Item width	Geodatabase field type

B	4	long integer

C	1–320	text

D	8	date

F	4	float

F	8	double

I	1–4	short integer

I	5–9	long integer

I	10–16	double

N	1–9	float

N	10–16	double


Spatial Reference

When creating a stand alone feature class or creating a new feature dataset, the coordinate system and the domain extents will match that of the input data. Click Change Settings… then Change… to alter the output coordinate system, and the precision value and size of the domain extent.

If the input and output coordinate systems are different, the features will automatically be projected. When adding a feature class to an existing feature dataset the coordinate system for the output feature class will automatically be set to match the coordinate system of the feature dataset.

Individual features with coordinates outside the X, Y and Z domain of the feature dataset will not be added to the output feature class. The M domain is excluded from this rule, feature with M values outside the M domain will still be added to the output feature class.

The coordinate range or domain extent of the output feature class is determined by the minimum coordinate, the maximum coordinate, and Precision values. Precision defines the scale of the dataset. The scale is the number of system units per one unit of measure. Therefore, this value specifies the degree of resolution. For example, in a projection system with meters as the unit of measurement, a precision value of 100 would be used to maintain centimeter-level resolution. Decreasing the Precision value increases the domain extent.

M and Z values must be created at the same time as a feature class or feature dataset is created as they can not be subsequently added. If the Enable M values on the output is checked the output feature class will have linear measurement (M) values. If you do not want your new feature class and/or feature dataset to contain M values, uncheck this option.

Note: The default grid size value is in the units of the input projected coordinate system or geographic coordinate system. Changing the output coordinate system will require a new grid size, as it must be in the units of the output coordinate system. For example, if the input feature class has a geographic coordinate system and its units are decimal degrees, the default grid size may be 10. If the output coordinate system is set to be Lambert Conformal Conic with units in meters, the default grid size should be set to a value suitable for that new unit, such as 10000. If the default grid size is not updated, an error stating that the grid size is too small may occur or you may experience poor performance when working with the feature class as a result of an inappropriate grid size. If an error does occur, a new spatial index must be created for the feature class in ArcCatalog, before the feature class can be used.


Spatial Index Grid

The spatial index grid (see the Output Settings form, Grid Size tab) is a two-dimensional grid system that spans a layer, like the locator grid you might find on a common road map. It is used to quickly locate features in a dataset that might match the criteria of a spatial search. Careful creation of a spatial index will increase the efficiency of your spatial searches. If you are unfamiliar with creating spatial index grids, use the default value provided, as creating a poorly defined grid will increase the time needed to complete a spatial search.

One to three 2-D grids (also referred to as grid levels), each with a distinct cell size, are created for an SDE layer. The first, or lowest, grid level has the smallest cell size.  Set the cell sizes of the other grids to 0 if you only want one, otherwise set each level at least three times larger than the previous level.


Coverage to IGDS Wizard

Converts a coverage into an Interactive Graphics Design Software (IGDS) file.

Notes

The wizard assumes that your coverage is in working units. It converts the coverage working units into units of resolution using working units information found in the seed file.

If a coverage feature was originally a complex element translated from a design file and it has no associated attribute linkages, the wizard will use the same attribute linkages for that feature as the ones used for its complex element header, if they exist.

To ensure attribute linkages are preserved in the translation from coverage to design file, be sure you have either an alink system file or one or more INFO linkage tables. The Coverage to IGDS Wizard extracts attribute linkages first from the system alink file, of it exists. If you want attribute linkages to be read from your linkage tables, delete your alink system file. See the Related Topics for more information on linkage tables.

The wizard assumes that the ACODE file contains one record for each coverage feature.

Complex strings will always be constructed from line strings. IGDS line strings cannot have more than 100 points. Any arc with more than 100 points will be written as a series of line strings unless the Complex lines option has been checked

Supported file extension

Related Topics


Property map options

The property map is an INFO table containing items as shown in the example below. The property map can be used when the Input coverage is created by some means other than using the IGDS to Coverage Wizard (i.e., when there is no ACODE file). Graphic attributes such as level, color, style, weight, graphic group number and class can be controlled or assigned by using a property map. The INFO table can have any name. One record may be present for each feature that is being converted. That feature name will be in the FEATURE item. Items are defined as 42,42,C.

PROP.MAP

ITEM NAME   WIDTH   OUPUT   TYPE
FEATURE      42      42       C
LEVEL        42      42       C
GGNO         42      42       C
CLASS        42      42       C
PROPS        42      42       C
COLOR        42      42       C
STYLE        42      42       C
WEIGHT       42      42       C
TEXT         42      42       C

If a property map is not specified, if a record does not exist for a feature being converted, or if the value specified is not appropriate, then output elements will be assigned the following default values.

LEVEL   1
GGNO    0
CLASS   0
PROPS   00000100
COLOR   0
STYLE   0
WEIGHT  0
TEXT

The following is an example of how you might use the property map. First we create an INFO table which we will call PROP.MAP. Listing the table, we see

PROP.MAP

    1
FEATURE = ANNO
LEVEL   = 17
GGNO    = 3
CLASS   =
PROPS   =
COLOR   = 3
STYLE   =
WEIGHT  =
TEXT    =

In record one, we have designated that all annotation (ANNO) features be output on level 17 with a graphic group number (GGNO) of 3 and a color value of 3. Since we have not put any value in for CLASS, PROPS, STYLE, or WEIGHT, default values will fill these parameters.

Occasionally, it may be necessary to assign different graphic attributes to the same element type. Any of the property map items may contain an item name from the feature attribute table of the feature being translated (e.g., AAT for arcs, PAT for polygons or points). In such cases, the translator will get the value for that item and use it in the translation. Items in the feature attribute tables, used to store graphic attributes, should be defined using the standard IGDS item definitions.

For example, we have a coverage called ROADS that has multiple road types. We want to translate the ROADS coverage and assign each different road type a different level value. The ROADS.AAT file has an item called ROADS_CODE which has code numbers defining interstates, U.S. highways and state highways. We want the ROAD_CODE value for each road to be the IGDS level in the output design file.

We create a property map file called ROADPROP.MAP. The LEVEL item has a value of ROAD_CODE for the arc feature record. An item called ROAD_CODE, containing the level numbers for each N-ARC, is added to the ROADS.AAT file. It is defined the same as the standard IGDS item IGDS-LEVEL, 2 2 I.

ROADPROP.MAP
   1
FEATURE  = N-ARC
LEVEL    = ROAD_CODE
GGNO     =
CLASS    =
PROPS    =
COLOR    =
STYLE    =
WEIGHT   =
TEXT     =

The Coverage to IGDS Wizard will see that the property option is used, see the value of ROAD_CODE for LEVEL and look in the ROADS.AAT for an item called ROAD_CODE. The output element line strings will have level values that equal the ROAD_CODE values (e.g., if interstates have a ROAD_CODE of 10, then the output line string for interstates will be on level 10).


Converting points to cells

If you want to use a property map file to translate points into cells, the TEXT item for point features in the property map needs to contain the name of the cell. Also, the Features should be either point or tic and the Elements must be cell. The Coverage to IGDS Wizard will look in the TEXT item of the property map for a cell name. If it finds a cell name, it copies and translates the cell with that name from the cell library to the output design file. Scaling is not done.

For example, if you have a cell library called test.cel that contains cells named SUBDIV, you would put the word SUBDIV in the TEXT field of the property map record for POINT features

If a property map is not used or there is no value for TEXT in the property map, depending on the Features, a default value of TIC or POINT is used for searching in the cell library.

When a point is converted to a cell and the ACODE option is used, the cell name will be taken from the IGDS-TEXT item in the Input coverage.ACODE file.

In some cases, cells in the cell library will contain previously defined cells. These previously defined cells are not copied to the new design file. In other words, recursively defined cells are not supported. If the wizard encounters a cell library where this situation exists, it will give you a warning message and proceed with the translation.


Features and elements

When a coverage is converted using an existing ACODE file or when it was not created by the IGDS to Coverage Wizard, you control the input features, giving you a great deal of control over the output elements. However, when a coverage was created from a design file and attributes are defined by the source design file, the selected Features will be converted to their original element types regardless of what Elements are specified. If the Coverage to IGDS Wizard encounters elements in the source design file that it can not convert a feature to, the translator will convert the feature to its default element type. If the original element is a cell, the cell will be copied from the source design file and scaling information will be preserved.

This chart summarizes input features and their valid output elements. The default output element for each input feature is listed first in bold type.

Features	Elements

Annotation	Text, Textnode

2-point arcs	Line, Linestring

Multi-point arcs	Linestring, Curve, Complex String, Complex Curve

Curves	Arc, Linestring, Curve, Complex String, Complex Curve

Points	Line, Text, Textnode, Cell

Polygons	Complex String, Complex Curve, Complex Shape

Tics	Line, Text, Textnode, Cell

Feature and element definitions


Feature and element definitions

Features

Annotation - all annotation from all subclasses in the input coverage will be converted.

2-point arcs - converts arcs with only two vertices.

Multi-point arcs - converts arcs with more than two vertices.

Curves - converts curves defined by COGOEDIT. The input coverage must have COGO attributes in the AAT file to use this input feature.

Points - converts point features.

Polygons - converts arcs that make up polygon features.

Tics - converts tic features.

The wizard defaults to having 2-point arcs and Multi-point arcs, unless the input coverage has COGO attributes in the AAT, in which case it defaults to 2-point arcs, Multi-point arcs and Curves.

Elements

Cell - a complex element defining a group of elements that describes a symbol. Each cell has a six-character name that will be read from the IGDS-TEXT item in the ACODE file or the TEXT item in the property map file.

Line - a two-vertex line or point. Lines with the same beginning and ending vertices represent points.

Linestring - a multi-vertex line. The maximum number of vertices an IGDS line string can have is 101.

Textnode - a complex element defining a group of text elements having common characteristics, such as a paragraph where each line is a text element. Textnode components are converted from independent text elements sharing a common complex element ID in the IGDS-CPXID item in the ACODE file. If Textnode is specified as an Element, text height and width multipliers are taken from the type 9 element in the seed file.

Complex String - a complex element defining a group of connected linear elements (line, line string, curve and arc). Complex String components are converted from independent elements sharing a common element ID in the IGDS-CPXID item of the ACODE file.

Complex Shape - a complex element defining a group of connected shape elements that closely resembles polygon features. Complex shape components are converted from line features that make up polygons.

Arc - an arbitrary section of an arbitrary ellipse.

Text - text string read from the IGDS-TEXT item in the ACODE file or the TEXT item in the property map file.


Input coverage to be converted into an IGDS file.


Name of the cell library used to define cells.


An INFO data file with the items FEATURE, LEVEL, GGNO, CLASS, PROPS, COLOR, STYLE, WEIGHT and TEXT.  The file is used to define graphic attributes for output elements.


Output IGDS file name.


Determines whether line strings with more than 100 points are written as complex lines or not. The Complex option writes all arcs with more than 100 points as complex elements.  Otherwise, all arcs with more than 100 points are written as several line strings and curves.


Specifies whether the output design file is written as a two dimensional or three dimensional file. Each element has a single z-value.


Anno - all annotation from all subclasses in the input cover will be converted.


2-Arc - converts arcs with only two vertices.


N-Arc - converts arcs with more than two vertices.


Curve - converts curves defined by COGOEDIT. The input cover must have COGO attributes to use this feature.


Point - converts point features.


Poly - converts arcs that make up polygon features.


Tic - converts tic features.


Cell – a complex element defining a group of elements that describes a symbol.

Line – a two-vertex line or point.  Lines with the same beginning and ending vertices represent points.

Linestring – a multivertex line.  The maximum number of vertices an IGDS line string can have is 101.

Textnode – a complex element defining a group of text elements having common characteristics, such as a paragraph where each line is a text element.

Complexstring – a complex element defining a group of connected linear elements (line, line string, curve and arc).

Complexshape – a complex element defining a group of connected shape elements that closely resembles polygon features.

Arc – an arbitrary section of an arbitrary ellipse.

Text – text string read from the IGDS-TEXT item in the ACODE file or the TEXT item in the property map file.


The output IGDS file will not have attribute linkages. Properties will be taken from the property map. If the property map is not specified, default values will be used for each output element’s properties.


Graphic attributes such as level, graphic group number, and so on, will come from the .ACODE file. The output IGDS file will have attribute linkages if there is a .USER, DMRS or STDDB linkage table or an .alink system file in your current workspace directory.


Translation instructions will come from the seed file. This should be the same file used to create the input cover (using IGDSARC). Attribute linkages and properties will come from elements in the source design file.


Interactive Graphic Design Software (IGDS) files and MicroStation design files can be translated into ArcInfo coverages with the IGDS to Coverage Wizard. ArcInfo coverages can be translated into design files with the Coverage to IGDS Wizard. IGDS and MicroStation design files both have the same file structure and are both referred to as DGN files. Both are binary files organized into levels containing one or more drawing elements, or entities, and both can be read by the IGDS to Coverage Wizard. Graphic attributes are stored in the design file but database attributes are not. Instead, each element can store pointers to attributes in external database files. These pointers, or linkages, are preserved during the conversion.


Complex lines

Complex strings will always be constructed from line strings. IGDS line strings cannot have more than 100 points. Any arc with more than 100 points will be written as a series of line strings unless the Complex lines checkbox has been checked.

3D files

The 3D file option is used to create a three dimensional design file. This option is valid only when the Input coverage was created from an IGDS file and a three dimensional seed file is used. The z-values used to construct 3D IGDS design file elements are read from the IGDS-ZVALUE in the Input coverage ACODE file.

For example, for ArcInfo coverage ZCOV the item IGDS-ZVALUE has been added to the ACODE file and populated with elevation values.

ITEM NAME       WIDTH   OUTPUT   TYPE   N.DECZ
COV-ID            4       5        B
IGDS-LAYER       16      16        C
IGDS_TYPE         3       3        I
IGDS-LEVEL        2       2        I
IGDS-GGNO         5       5        I
IGDS-CLASS        1       1        I
IGDS-PROPS        8       8        C
IGDS-COLOR        3       3        I
IGDS-STYLE        1       1        I
IGDS-WEIGHT       2       2        I
IGDS-TEXT        12      12        C
IGDS-FONT         5       5        I
IGDS-ZVALUE       8      10        F    3
IGDS-CPXID        4       5        B
IGDS-CPXYPE       3       3        I
IGDS-OFFSET       4       7        B

There is one elevation value for each feature.

ZCOV.ACODE

ZCOV-ID                    = 1
IGDS-LAYER                 = ELEVATION
IGDS-TYPE                  = 4
IGDS-LEVEL                 = 4
IGDS-GGNO                  = 225
IGDS-CLASS                 = 0
IGDS-PROPS                 = 00000110
IGDS-COLOR                 = 4
IGDS-STYLE                 = 0
IGDS-WEIGHT                = 0
IGDS-TEXT                  =
IGDS-FONT                  = 0
IGDS-ZVALUE                = 1548.000
IGDS-CPXID                 = 0
IGDS-CPXTYPE               = 0
IGDS-OFFSET                = 39989

The 3D header information for out_3d.dgn is constructed from header information found in the 3D seed file. If the Input coverage was created from a 3D design file using the IGDS to Coverage Wizard, then use the original design file as the input seed file to ensure correct design file header information. The IGDS-ZVALUE item will exist in the ACODE of a coverage generated by the IGDS to Coverage Wizard if the file is 3D. This item stores the first z-value encountered during the translation of each element.


Seed File

Any design file containing type 5, 8, 9 and 10 elements. These elements are templates for the corresponding type 5, 8, 9 and 10 elements in the output IGDS file. The type 9 element will be used to determine the MU:SU:PU mapping from coverage units. One coverage unit will be mapped into one master unit. This file is used to reconstruct complex environmental information in the IGDS file. If the Source IGDS option is used, then this file is also used to reconstruct original output elements. The seed file should be an existing IGDS file in the same mapping units that you want the coverage converted to. If you do not have access to an IGDS file, there are sample files in the $ARCHOME\template\igds directory.


Coverage to IGES

Converts an ArcInfo coverage into an Initial Graphics Exchange Standard (IGES) Version 3.0 uncompressed ASCII file. The tool converts coverage features to IGES entities as follows:

Arcs	IGES Entity 106 (Copious Data Entities)

Points	IGES Entity 116 (Point Entities)

Annotation	IGES Entity 212 (General Note Entities)

Notes

At least one coverage must be specified.

To convert the arcs of a polygon coverage, first use the Build tool with Feature class Line to create an arc attribute table (AAT) . Then use the polygon coverage name as the Input line coverage. Label points can be converted by specifying the same polygon coverage as the Input point coverage.

Header file format and description

Coverage attributes used in the conversion

Related Topics


IGES files are published by the U. S. Department of Commerce. This format is often used to transfer CAD data between systems.


Header file format and description

The Input header file contains items to be written to the Start and Global sections of the new IGES file. The format and default values for the Input header file are shown below. This file may use any or all of the following lines:

AUTHOR <string> – The name of the person responsible for generating this data. The default is blank.

ORGANIZATION <string> – The group or organization with which the author is associated. The default is blank.

SCALE <real_number> – The ratio of the drawing to real-world units. The default is 1.0.

MAXLINEWIDTH <real_number> – The maximum allowable line width in the drawing. The default is 0.0, which represents one pen width.

RECEIVINGID <string> – The receiving system identification name or identifier to be used to reference this file. The default is the output file name.

SENDINGID <string> – The product identification from the sender used to reference this file. The default is the output file name.

SYSTEMID <string> – The identification code which uniquely identifies the system which generated this file. It should include both the name of the system and the version of software on that system. The default is blank.

UNITS <FEET | METERS | INCHES | CENTIMETERS | MILLIMETERS | MILS | MICRONS | MICROINCHES | MILES | KILOMETERS> – Coverage coordinate units. The default is FEET.

/* {string} – Comments to be entered in the Start section of the IGES file.

END – Last statement in the Input header file. This is required to end the file.


Coverage attributes used in the conversion

Attribute information for lines and points will be taken from standard IGES items found in the Input line coverage and Input point coverage. These are the same standard IGES items created by the Arc IGESARC command. If there are no IGES items in the PAT and AAT files, the ACODE and XCODE files will be searched. Standard IGES item values will be written to the Output IGES file for the following items:

Item name        Type       Description

IGES-FONT-PAT    Numeric    IGES line font pattern
                (B, I,      number for the IGES
                 F or N)    feature’s directory
                            entry (DE) field #4

IGES-LEVEL       Numeric    IGES level number for
                            the IGESfeature’s DE
                            field #5

IGES-LINE-WT     Numeric    IGES line weight number
                            for theIGES feature’s
                            DE field #12

IGES-COLOR       Numeric    IGES color number for
                            the IGESfeature’s DE
                            field #13

IGES-ENTITY-LAB  Character  IGES Entity Label for
                            the IGESfeature’s DE
                            field #18

IGES-ENTITY-SUB  Numeric    IGES Entity Subscript
                            Number of the feature’s
                            DE field #19

IGES-ELEVATION   Numeric    Constant value for the
                            feature(F) written to
                            the first x,y,z
                            coordinate in the
                            parameter section

Annotations from all existing subclasses for the specified Input anno coverage will be written to the IGES file.

The IGES version 3.0 format, published by the U.S. Department of Commerce – National Bureau of Standards, includes three file formats: uncompressed ASCII, compressed ASCII and binary. Coverage to IGES creates the uncompressed ASCII Version 3.0. Program listings for conversion between the three IGES formats are available with the IGES format specification documentation.

The value in IGES-ELEVATION will be written to the IGES file as a constant z value for the feature. The first set of coordinates will be written in x,y,z format. The z coordinate represents a constant plane that all data points lie on. The remaining coordinates for the feature will be written as x,y coordinate pairs.

If no IGES attributes are found in the coverage’s feature attribute tables or associated tables, the output IGES file will be created, but without attributes.


The coverage with arcs you want to convert to IGES format.

NOTE: To convert the arcs of a polygon coverage an AAT file must exist. Use the Build tool with the Line option to create an AAT file.


The coverage with points you want to convert to IGES format.

NOTE: To convert polygon label points, enter the polygon coverage with label points you want to convert to IGES format.


The coverage with annotation you want to convert to IGES format.


The file with information you want to include in the Start and Global sections of the IGES file. If it does not already exist, you can create it by clicking the adjacent browser button and then clicking ‘Yes’ to start the Header and Control File Builder.


The IGES file you will create.

NOTE: This file will be in the IGES Version 3.0 uncompressed ASCII format.


Coverage to MOSS

Converts a coverage to a MOSS export file.

Notes

Coverages to be converted into a MOSS export file must already be projected into UTM or LAT/LONG coordinates.

This tool will represent polygons in the MOSS export file as closed loops possibly containing islands.

MOSS export files represent polygon islands using the polarity (i.e., positive or negative) of the x-coordinate to indicate a jump to an island. ArcInfo coverages crossing the y-axis should be transformed to have either entirely positive or entirely negative x-coordinates.

MOSS files in UTM have (undocumented) data limitations that differ from ArcInfo limitations. Care should be taken when converting polygons to MOSS. Even though this tool can write out any ArcInfo polygon regardless of the number of coordinates, MOSS may not be able to import them to create a MOSS polygon.

Supported file extension

Related Topics


The coverage you want to convert to MOSS format.


Choose the feature class you want to convert.

Poly – polygons

Line – arcs

Point – points


The items listed are from the specified Feature class attribute table. Choose the item whose values you want to use as the subject (a 30-character attribute field in the MOSS file) value.

If you choose None, the MOSS file subject field will be blank.

If you choose a Lookup table, the Attribute item will be used to relate to this table.


The Lookup table must have the following two items:

Lookup item – must be named and defined the same as the Attribute item.

DATA – stores the attribute text that will be used as MOSS subject value for each Lookup item. Can be any supported item type.


The MOSS file you will create.


A MOSS export file is an ASCII formatted file readable by the U.S. Department of Interior’s MOSS public domain GIS. The polygon boundaries and a 30-character attribute field, called the subject value, are written to the file.


The subject is a 30-character attribute field in a MOSS file.


Export to SDTS

Creates an SDTS Topological Vector Profile (TVP), Point or Raster profile transfer from a coverage or grid.

The following conditions must be met when creating a TVP transfer.

The following conditions must be met when creating a Point profile transfer.

The following conditions must be met when creating a Raster profile transfer.

The output SDTS transfer dataset must be placed in a directory that does not already contain a SDTS transfer. The tool will not overwrite existing files, so the tool will fail if required output files already exist. A common method is to create a new directory for each transfer. A new output directory can be created in the output browser.

Notes

The ArcInfo coverage must have polygon topology when converted to a TVP transfer. It may also be built for line and node topology and may contain annotations, regions and routes. All items in the polygon attribute table and all items in the optional arc and node attribute tables, and subclasses will be written to the transfer. They will be written to primary attribute modules with direct links to their corresponding spatial object modules. Annotation will be ignored.

The Input point coverage is used only when creating a TVP transfer.

All attribute tables with the same Input dataset or Input point coverage prefix will be written to the transfer as secondary attribute modules. If either <Input dataset>.REL or <Input point coverage>.REL relate tables exist, they will not only be written out as secondary attributes but will also be used in global modules to provide more information to the receiving system about table relationships.

Log and tolerance files will be written to the SDTS transfer.

Conversion control file commands

Related Topics


The coverage or grid you want to convert to SDTS format.


The 4-character prefix common to all SDTS transfer files you will create. For example, ‘1998’, ‘hy01’, or ‘soca’ are valid prefixes.

NOTE: You must create a transfer directory. The files will not be created in the directory that also stores the coverage you want to transfer.


Opens a browser to specify the prefix and location for the output SDTS transfer.


The point coverage you want to include in the SDTS transfer. This input is optional for a TVP transfer and is not valid for other profile types.


The 4-character prefix for the master data dictionary files that will be created in a directory called “masterdd”. This output is optional. Examples of valid prefixes are ‘expo’, ‘25mz’, and ‘0001’.

NOTE: Do not specify a path.


Specify a file containing information you want to append to files in the SDTS transfer during the conversion process. If it does not already exist, you can create it by clicking the adjacent browser button and then clicking ‘Yes’ to start the Header and Control File Builder.


Conversion control file

The Conversion control (ctrl) file's size should be kept to a minimum whenever possible.

Those commands dealing with Data Dictionary modules (i.e Authority, SrcDefinition, DDDefinition, DDDomain) are not intended to be used as a means to create and define the "entire" data dictionary with the conversion control file. They should only be used as a means to "modify and update" a small number of data dictionary records.

An attribute label's data dictionary information in a DDDF module will  be altered if and only if a DDDefinition statement mentioning the attribute label exists in the conversion control file.

/* comment line
Comment line string

END
End of conversion control file.

The control file commands allow you to convert INFO tables that are not named using the Input dataset prefix. They can also be used to override default global information and information read from standard SDTS INFO tables.

Export commands valid in a Global control block

Other Export commands

Commands specifically for Point profile

Commands specifically for Raster profile

Sample control file


Export commands valid in a Global control block
(Scope: Global)

TABLE <INFO_name> {IGNORE} – Allows conversion of INFO tables other than the default. The default INFO tables are those have the same base name as the Input dataset name or Input point coverage name if specified.

TITLE <string> {MasterDD} – For Title subfield in IDEN or MIDE module, where max string is 1024 characters long.

VERSION <d.nn> {MasterDD} – For Data ID subfield in IDEN or MIDE module. Where d = a positive integer, with no leading zeros, and nn = two-digit positive integer.

MAPDATE <YYYYMMDD> – For Map Date subfield in IDEN module.

CREATIONDATE <YYYYMMDD> {MasterDD} – For Date set creation date subfield in IDEN or MIDE module.

MAPSCALE <scale>  – For Map scale subfield in IDEN module.

CONFORMANCELVL <level> {MasterDD} – For Conformance feature level subfield in IDEN or MIDE module, where <level> is 1, 2, 3 or 4.

SCALEFACTOR {sfax} {sfay} – For X and Y scale factor subfields in IREF module, where {sfax} {sfay} are real values.

SHIFT {xorg} {yorg} – For X and Y origin subfields in IREF module, where {xorg} {yorg} are real values.

HORIZONTALRES {xhrs} {yhrs} – For X and Y component of horizontal resolution subfields in IREF, where {xhrs} {yhrs} are real values.

COMMENT <TEXT | FILE> <module_name> <string> – For Comment subfields in MIDE, IDEN, IREF, XREF, or SPDM module. If <FILE> option is specified, then the entire ASCII file's content will be saved in the targeted module subfield.

ADDRECORD <TEXT | FILE> <DQ_Module_Name> <string> – For Comment subfields in MQCG, MQHL, DQAA, DQCG, DQHL, DQLC, or DQPA module. If <FILE> option is specified, then each line in the ASCII file will create a record in the targeted module. A line is defined as Carriage-Return/Line Feed (CR/LF). Blank lines are skiped.


Other export commands

AUTHORITY <Attr_/Entity_Authority> <Authority_Description> – Scope: Global & FeatureClass & Table. Set attribute (or entity) authority, and full description. If the authority is another FIPS standard, then specify FIPS as authority and give full reference as description. The AUTHORITY statement in the Global control block will also affect the contents of README file for TVP transfer and MasterDD transfer.
Default: Authority ::= "unknown".
Authority_Desc ::= ""

Example: AUTHORITY ESRI 'Environmental System Research Institute, Inc.'

DDDEFINITION ENT <Entity_Label> {Entity_Label_Definition} {Source_Definition}
DDDEFINITION ATT <Attr_Label> {Attr_Label_Definition} {Source_Definition} – Scope: FeatureClass & Table. Allow definition of Entity label or Attribute label (i.e. subfield) to be translated into the Data Dictionary/Definition module as a record.

*** IMPORTANT NOTE: ***
An attribute label's data dictionary information in DDDF module will be altered if and only if the DDDefinition statement exists in the conversion control file and it mentions the attribute label

Example:
DDDEFINITION ATT BANK "Describe river bank" "TIGERI Dictionary"
DDDEFINITION ENT 0500206 "This code identifies Danger curve"

DDDOMAIN <Attr_Label> <Domain_Type> <Domain_Val_Format> <Measure_Unit> <Range_or_Value> <Domain_Val> <Domain_Val_definition> – Scope: FeatureClass & Table. This command allows the setting of attribute label's value domain (i.e., range).

Examples:
DDDOMAIN BANK ENUMERATED A "" VALUE "" "Not Applied"
DDDOMAIN BANK ENUMERATED A "" VALUE L "River left bank"
DDDOMAIN BANK ENUMERATED A "" VALUE R "River right bank"

EXPORT – Starting of export section, use as conversion control by SDTSEXPORT.

FEATURECLASS <Arc_FeaCls{.sub_cls}> {IGNORE} – This marks the beginning of an ArcInfo feature classes block. All commands in the block will only apply to this one feature class. Ended with the next FEATURECLASS, TABLE, END or IMPORT command.

IGNOREITEM <Item1> {Item2} . . . {Item9} – Scope: Global & FeatureClass & Table. Ignore INFO items (Maximum 9 items) so that they do not get translated into SDTS module.

ITEMBECOMES <item> <Attr_Label> {Format} {Max_length} {Key_Type} {Measurement_Unit} {Description} – Scope: Global & FeatureClass & Table. SDTS attribute label (subfield) definition for an INFO item instead of using the default definition.

Defaults:
{key_Type} = NOKEY
{Measurement_Unit} = ""
{Description} = <Attr_Label>

See ItemBecomes Options.

SRCDEFINITION <Source_Definition> – Scope: Global & FeatureClass & Table. ENT or ATT labels' source of definition.

Examples:
SRCDEFINITION 'ARC/INFO Data Model, Concepts, & Key Terms'
SRCDEFINITION "TIGERI Dictionary"

TABLE <INFO_name> {IGNORE}
TABLE <INFO_name> {out_module_name} – Optional TABLE control block(s), which allow conversion of INFO tables other than the default. The default INFO tables are those having the same base name as the Input dataset name or Input point coverage name if specified.

<Format> = <Domain_Val_Format> | < ^ > /* Packed foreign identifier (see 4.1.3.6.7) */


Commands specifically for Point profile

HorizontalFmt    <BFP64 | BI32>HFMT   <BFP64 | BI32>

Note: HFMT is short for HorizontalFmt. You can use this keyword to specify the HFMT sub-field in the IREF module. If you do not use this keyword to specify the horizontal format, the default value BFP64 will be used (i.e. high precision double).


Commands specifically for Raster profile

CellNull  <null_value> – Set output null value when exporting grid NODATA cells. If you do not specify the cell null value, the following values will be used according to cell type

Cell type        Cell null
I              -2147483647
R              -2147483647
BI8                   -127
BI16                -32767
BI32           -2147483647
BUI8                   255
BUI15           4294967295
BFP32          -2147483647

CellLabel <label_string> – Set the output cell value sub-field label. If it is not specified, "LABEL" will be used.

CellSequenceCode <GI|GL|GJ> – When exporting mulitple grids (i.e. layers), module RSDF, sub-filed CSCD can be set through this keyword. If not specified, "GI" will be used.


Sample control file

EXPORT

/*-------------------------------------------------------------
/* Global Section: setting global variables for conversion.
/*-------------------------------------------------------------

/*-- Setting subfields values in IDEN and MIDE module
/*--
Title <string> {MasterDD}
Version <d.nn> {MasterDD}
MapDate <YYYYMMDD>
CreationDate <YYYYMMDD> {MasterDD}
MapScale <scale>
ConformanceLvl <level> {MasterDD}

/*-- Setting subfields values in IREF module
/*--
ScaleFactor {sfax} {sfay}
Shift {xorg} {yorg}
HorizontalRes {xhrs} {yhrs}

/*-- Setting comment(COMT) subfield value in
/*-- MIDE, IDEN, IREF, XREF, or SPDM module.
/*--
Comment TEXT IDEN "Comment from Conv. Ctrl. File...comt 1"
Comment FILE IREF "/disk1/sdts/comt.iref"

/*-- Set comment(COMT) subfield value in Data Quality modules
/*-- MQCG, MQHL, DQAA, DQCG, DQHL, DQLC, DQPA module.
/*--
AddRecord TEXT DQHL "Comment from CCF...comt A"
AddRecord TEXT DQAA "Comment from CCF...comt B"
AddRecord TEXT DQPA "Comment from CCF...comt C"
AddRecord TEXT DQCG "Comment from CCF...comt D"
AddRecord TEXT DQLC "Comment from CCF...comt E"
AddRecord FILE DQLC "/disk1/sdts/comt.dqlc"

/* Set global ENT and ATT authority, and their source of definition
/*--
Authority WXYZ "W.X.Y.Z, Inc."
SrcDefinition "W.X.Y.Z data dictionary"

/* For this conversion process ignore the following INFO items whenever
/* applicable for all feature classes and table blocks.
/*--
IgnoreItem WIDTH

/*---------------------------------
/* Node
/*---------------------------------
FeatureClass NODE IGNORE

/*---------------------------------
/* Arc
/*---------------------------------
FeatureClass ARC

Authority EFG "E.F.G, Inc.,"
SrcDefinition "E.F.G attribute data dictionary"

IgnoreItem DEPTH
ItemBecomes VOLUME VOLUME_ R 12 nokey # 'CCF volume definition'

DDDefinition ATT VELOCITY "Water flow velocity"
DDDomain VELOCITY REAL R "feet per sec" MIN 2.5 "Minimum speed"
DDDomain VELOCITY REAL R "feet per sec" MAX 10.0 "Maximum speed"

Authority ABC "A.B.C, Inc.,"
SrcDefinition "A.B.C attribute data dictionary"

DDDefinition ATT BANK "Definition for river's bank."
DDDomain BANK ENUMERATED A "" VALUE "" "Not Applied"
DDDomain BANK ENUMERATED A "" VALUE L "River left bank"
DDDomain BANK ENUMERATED A "" VALUE R "River Right bank"

/*---------------------------------------
/* Table: Drop look up table RIVER.LUT
/*---------------------------------------
Table river.lut IGNORE

/*---------------------------------
/* Table:
/*---------------------------------
Table \disk2\sdts\soil.lut

IgnoreItem DENSITY
ItemBecomes SOIL_TYPE SOILTYPE ALPHANUM 16 NOKEY # 'CCF soil type definition'

END


<Arc_FeaCls{.sub_cls}> = < ARC | NODE | POINT | POLY | TIC | LINK | BND | ANNO.subcls | SECTION.subcls | ROUTE.system | REGION.subcls >


<Domain_Type> = < GR-CHARS | ALPHANUM | ALPHABET | INTEGER | REAL | BINARY | ENUMERATED | FIPSCODE >


<Domain_Val_Format> =
< A /* Graphics Characters */
| I /* Implicit-point (integer) */
| R /* Explicit-point unscaled (fixed point real) */
| S /* Explicit-point scaled (floating point real)*/
| B /* Bitfield data */
| BFP32 /* 32-bit floating point real */
| BFP64 /* 64-bit floating point real */
| BI8 /* 8-bit signed integer */
| BI16 /* 16-bit signed integer */
| BI24 /* 24-bit signed integer */
| BI32 /* 32-bit signed integer */
| BUI8 /* 8-bit unsigned integer */
| BUI16 /* 16-bit unsigned integer */
| BUI24 /* 24-bit unsigned integer */
| BUI32 /* 32-bit unsigned integer */
| C /* Character */
>


<Key_Type> = < NOKEY | PKEY | FKEY | PFKEY >


<Range_or_Value> = < VALUE | MIN | MAX >


<DQ_Module_Name> = < DQHL | DQPA | DQAA | DQLC | DQCG | MQCG | MQHL >


<TEXT> = the <string> argument is treated as regular text string.


<FILE> = the <string> argument is treated as path name to a ASCII text file and the contents of it will be save into the target module's subfield.


ItemBecomes Options

ItemBecomes:
----------------+---------------------------------------------
| SDTS data type
INFO data type | A I R S C B16 B32
----------------+---------------------------------------------
D | 1 X X
C(n) | 1
I(1-16) | 1
N(1-16) | 1
B(2 bytes) | 1
B(4 bytes) | 1
F(4 bytes) | 1
F(8 bytes) | 1
----------------+---------------------------------------------
KEY:
1 – Default data type for given INFO data type.
X – Invalid data type for given INFO data type else valid.


Choose the type of SDTS profile you want to create.

TVP – Topological Vector Profile, designed specifically for planar vector data with topology.

Point – Point Profile, designed for high precision point data sets.

Raster – Raster Profile. Grids and lattices are supported.


The Spatial Data Transfer Standard (SDTS) is a data exchange format for transferring different databases between dissimilar computing systems, preserving meaning and minimizing the amount of external information needed to describe the data. In the future, all Federal digital map data will be made available upon request in SDTS format. SDTS is documented in FIPS publication 173, available from the U.S. Department of Commerce.


Requirements for converting to a TVP transfer:

The ArcInfo coverage must have polygon topology.

The ArcInfo coverage must not have a mask file, only clean coverages will export.

The ArcInfo coverage must have a projection defined or it will not be exported.


Requirements for converting to a Point profile transfer:

The ArcInfo coverage must have point topology.

The ArcInfo coverage must have a projection defined or it will not be exported.


Requirements for converting to a Raster profile transfer:

The ArcInfo grid must have a projection defined or it will not be exported.


Coverage to Shapefile

Writes feature attributes or INFO records to a new shapefile.

Notes

All occurrences of "#" and "-" in INFO item names will be replaced with an underscore character. This includes COVER# and COVER-ID. Due to this substitution, item names "COVER_" and "COVER_ID" are reserved and should not exist in the Input coverage’s attribute tables. Coverage to Shapefile checks to see if the substitution will result in duplicate item names. A warning message is returned and the conversion process is stopped if duplicates will be created.

If an INFO item name is longer than 10 characters a message will be displayed telling you the new Field name that has been truncated to meet the dBASE limit. The Define mapping option will automatically be selected when this message is displayed.

The maximum record length for a dBASE data file is 4000 bytes. The maximum for an INFO data file is 4096 bytes. Coverage to Shapefile will issue a warning message if the dBASE limit is exceeded but will continue. The record length is the number of bytes required to define all of the items or fields in a table.

The maximum number of fields for a dBASE data file is 255. Coverage to Shapefile will convert the first 255 items if this dBASE limit is exceeded.

Coverage to Shapefile checks for duplicate item names resulting from illegal character substitution. It also issues a warning message any time an item name is changed.

If the Define mapping option is not used, Coverage to Shapefile truncates character fields longer than 254 to the first 254 characters and issues a warning message when this occurs.

Translation summary of features

Data type conversion issues

Related Topics


Translation summary of features

Feature Class	Shapefile Type

Point	Type 1 - Point
Tic	Type 1 - Point
Node	Type 1 - Point
Line	Type 3 - Line
Section	Type 3 - Line
Route	Type 3 - Line
Poly	Type 5 - Polygon
Region	Type 5 - Polygon
Annotation	Not supported


The coverage you want to convert to a shapefile.


Lists the feature classes available for conversion. This list includes one or all of the following:

Poly – converts polygons and their attributes

Line – converts arcs and their attributes

Node – converts nodes and their attributes

Point – converts points and their attributes

Region.<subclass> – converts regions of the selected subclass and their attributes

Route.<subclass> – converts routes of the selected subclass and their attributes

Section.<subclass> – converts sections of the selected subclass and their attributes

Tic – converts tics


The shapefile you will create.


The concept of shapefiles was adopted in ArcView version 2 to allow limited editing of theme information. This tool creates three files to store the geometry and dBASE attributes: <Output shapefile>.shp, <Output shapefile>.shx and <Output shapefile>.dbf.


Data type conversion issues

The data types between INFO and dBASE differ, making it necessary to map INFO data types into the appropriate dBASE data types.

Default data type conversion chart

When converting to an N type item, the total width will be at least two digits greater than the number of decimal places, as required by dBASE. For example, an item defined as 1,1,I will become 2,N in the output .dbf file. The tool cannot override this.


Choose the data type mapping from INFO items to dBASE fields.

Default mapping - performs the default item-to-field data type definitions.

Define mapping - you explicitly define the name of each dBASE field converted from the INFO items.


The currently selected INFO item contained within the selected Feature class. Select the item name you want to define in the new shapefile.


The name of the dBASE field that corresponds to the currently selected INFO item. The field name can not exceed 10 characters.


Coverage to SLF

Converts ArcInfo coverages into a Standard Linear Format (SLF) file. Although the SLF format does describe and include other data structures, the SLF-2-D ITD format is the only SLF format that the ArcInfo SLF translator supports.

Associated attribute tables, outlining the SLF attributes, must exist in order for conversion to occur. There must be a user defined item called FEACODE (5, 5, C), in these CODE tables which relate to the coverage’s feature attribute table. This item contains the 5 character SLF feature category for each feature. If you have non-SLF features, such as the universe polygon, then the FEACODE for these features should be blank.

An ACODE table contains the attributes for a coverage’s line features while a PCODE table contains the values for polygon features. Both tables must exist if the Poly & Line (Net) option is used. These tables are related to the AAT or PAT, using the Cover-ID, by the FEAT-ID (5,5,I) item. Refer to SLF standards for FEACODE values.

Notes

The Poly & Line (Net) option should be chosen if both line and polygon features exist in the Input coverage. Point features should not be in the same coverage as the line features.

If no name is specified for the Point coverage, point features will be taken from a coverage named Input coverage_p, if it exists. This follows the same naming conventions used when a coverage is generated by the SLF to Coverage tool.

The coverage coordinates must be in Geographic and must be based on the WGS 84 ellipsoid.

All coordinates must have positive values. The quadrant information is taken from information specified in the header section when the coverage is written out.

The lower left Tic-ID in the Input cover must be 1 and the upper right TIC-ID must be 3.

SLF supports complex features. The relationship between features of the same feature type is taken from associated INFO files. JOIN tables link features by ID numbers to feature attributes in CODE tables. Individual features may be components of more than one complex feature. These complex relationships are stored via the JOIN tables.

Attribute codes must be valid codes as described by NIMA’s DMAFF feature coding scheme for feature attribute coding.

SLF header file information

Supported file extension

Related Topics


SLF header file information

Header files store information (metadata) about the dataset by using keywords followed by one or more parameters. Keywords can be specified in any order. All are required in the header file, but only the DSPG-ORIGIN requires actual values to be input from you. The Header Builder adds all keywords you have not entered to the final header file, so you need only enter the keywords for which you have values. The keywords of the Input header file are shown in the following list:

Keywords

DSIG-PRODUCT {prod_type}

Product type; DITDT=1:50,000, Tactical Terrain Analysis Data, DITDP=1:250,000 Planning Terrain Analysis Database.

DSIG-DATASET {series}{sheet_number}{overlay...overlay}

Dataset ID number. The series designator is a five character alphanumeric code. Sheet number is a 5 digit number and the overlays are single character codes that represent layers included in this data set.

V = Vegetation

M = Surface Materials

D = Surface Drainage

T = Transportation

O = Obstacles

DSIG-EDITION {ed_number}

Edition number of the data set; numeric (1-999).; 1=New data set.

DSIG-SOURCE {compile_date} {maintenance_date}

The compile date is the date this data set was validated. The maintenance date is the date this data set was updated. Dates are entered as YYMM.(1-999).; 1=New data set.

DSIG-VERSION {SLF_date} {DMAFF_date}

The SLF and DMAFF version dates that this data applies to. Dates are entered as YYMMDD.

DSSG-CLASS{code}

Security classification code:

T = Top secret

S = Secret

C = Confidential

F = For office use only

R = Restricted

U = Unclassified

Code should be the highest given to the data set.

DSSG-SECURITY {rel_code} {declass_date}

Department of Defense security release code and declassification date.

DSSG-HANDLING {desc}

Department of Defense special security requirements; up to 21 chars.

DSPG-ORIGIN {lat} {long}

The latitude and longitude for the southwest corner of the data set. Latitude: DDMMSSSSH; Longitude: DDDMMSSSSH, where H = N,S,E or W

DSHG-HISTORY {edit_code} {product} {amend_num} {spec_date}

Edit_code is composed of a 2 digit compilation code and 1 digit revision code. 000= n. Products: SPECX050DITDT=1:50,000, and SPECX250DITDP=1:250,000. The amendment number is a 3 digit code as shown in the current specification document. Spec_date entered as YYMM. Reflects date of change or amendment to specification. Usually 8908.

DSHG-SYSTEM {producer} {digitizing_system} {process}

Producer is an 8 digit code;  USO90000=DMAHTC, USO90078=DMAAC. or a unique identification code provided by NIMA. Digitizing_system must be a valid NIMA digitizing system name or acronym.

DSHG-MATCH {N|E|S|W} {number} {date}

Set of Match/Merge numbers and dates for all Production Center-produced databases. Refers to the number of times the data has merged with the adjacent data in the specified direction; (1-9). The Merge/Match date is entered as YYMM.

DSHG-SOURCE {early_date} {late_date}

The dates of the earliest and latest sources used in the production of the data sets. Dates are entered as YYMM.

DSHG-COLLECT {criteria}

A three-digit code to denote a detailed reference in a specification document.

FEA-SOURCE {code} {scale_denominator} {date}

Source code for all features - a two digit code:

01 - Standard production source

02 - Cartographic litho source.

Scale denominator is the scale of source where 00250000 is 1:250,000 scale. Source date entered as YYMM.

FEA-COLLECTION {system}

A two digit code to denote the system:

00 – unknown

01 – ACDDS

02 – CPS

03 - FE/Station

FEA-MAINTENANCE {date}

Date of feature update entered as YYMMDD.

FEA-PRODUCT {base_product}

Largest scale product supported:

000 – unknown

001 - DFAD level 1

002 - DFAD level 2

003 – VOD

004 - DTAD TTADB 1:50,000

005 - PTADB 1:250,000

FEA-SECURITY {class_code}

Classification of feature classification:

T - Top Secret

S - Secret

C – Confidential

U – Unclassified

FEA-Portrayal {code}

A two digit code which describes scale range:

00 - Smaller than 1:1,000,000

01 - From 1:500,001 to 1:1,000,000

02 - From 1:250,001 to 1:500,000

03 - From 1:200,001 to 1:250,000

04 - From 1:150,001 to 1:200,000

05 - From 1:100,001 to 1:150,000

06 - From 1:75,001 to 1:100,000

07 - From 1:50,0001 to 1:75,000


The polygon coverage you want to convert to SLF format. This coverage may also have line topology.


Choose which features to convert.

Poly – converts only polygons and their attributes.

Poly and Line (Net) – converts polygons and lines and their attributes.


The header file contains information about the coverages that you want to include in the header section of the SLF file. This file must be included in the transfer. If it does not already exist, you can create it by clicking the adjacent browser button and then clicking ‘Yes’ to start the Header and Control File Builder.


The line coverage you want to convert to SLF format. This coverage must not contain points.


The point coverage you want to convert to SLF format.


The INFO table with attributes for miscellaneous text features.


The SLF file you will create.


The available input coverage options. Select one or all of these input coverage options.


The SLF format is primarily used to transfer the Interim Terrain Data (ITD) of the National Imagery and Mapping Agency (NIMA). This data product is produced by NIMA’s Feature Extraction Segment of the Digital Production System and is used as a terrain analysis product in various tactical systems.


Coverage to Generate File

Creates a text file of x,y coordinates for a coverage. The output text file is in a format that is readable by the Generate to Coverage Wizard. The tool provides a useful mechanism to create simple coordinate files from ArcInfo coverages. This allows you to easily transfer ArcInfo coverages to other mapping systems or to view and update individual coordinates using your computer’s text editor.

Generate file examples

Notes

User-IDs are written to the generate file for Lines, Points, Polys, Regions and Tics.

Files created by the tool are directly usable by the Generate to Coverage Wizard using the Points, Lines, Polygons, Tics or Links options.

The Exponential option writes coordinates in exponential notation, all significant digits are retained. This option is recommended if a high degree of coordinate precision is important. The Fixed option rounds coordinates off to 7 significant digits for a single precision Input coverage and 15 significant digits for a double precision Input coverage.

Files created with the Region.<subclass> option can also be used in the Generate to Coverage Wizard using the Line option, but to fully restore regions, further processing with the Line Coverage to Region tool and the Build or Clean tool is necessary.

When using the Poly option, polygons that are not properly closed will not be written to the Output file. Use the Arc command LABELERRORS to ensure that all polygons are closed and contain a single label point. If there are two label points in one polygon, only one will be written out. If no label point exists, then zero is written for the ID number of that polygon feature and the x,y coordinate for the centroid will be written.

The tool writes out a flag for island polygons. The island polygon will have an ID number of -99999 and a set of vertices defining the polygon. This is useful for converting ArcInfo polygon coverages to other systems that require special handling of island polygons.

The Poly option treats all line segments which are wholly contained within a polygon as island polygons and tags them with an ID number of -99999. Line segments that fall inside the polygon but touch the border of the polygon are also considered as islands inside the polygon. However line segments that fall outside a polygon are considered part of the universe polygon and are ignored.

All vertices that define each component arc of a polygon feature will be written out. To weed out vertices of very dense coverages, use the Generalize Lines tool prior to using Coverage to Generate File. The arcs for each polygon are written out starting at the lower left of the polygon and continuing in a clockwise direction. Arcs that are shared by more than one polygon will be duplicated in the Output file. Nodes and arc orientation are not preserved.

Related Topics


The coverage whose features you want to transfer.


Lists the feature class available for transfer. This list includes one or all of the following:

Line – transfers arcs coordinates.

Point – transfers label point coordinates.

Poly – transfers arcs and label point coordinates.

Tic – transfers tic coordinates.

Link – transfers coordinates that define links.

Region.<subclass> – transfers regions coordinates in the specified subclass.


Choose whether to retain duplicate node coordinates for polygons in the interchange file.

Checked – retains duplicate node coordinates for polygons

Unchecked – does not retain duplicate node coordinates for polygons.


The generate file you will create. The file cannot already exist.


Choose the generate file format:

Exponential - This option creates the  generate file in exponential notation.

Fixed – This option creates the generate file in a fixed representation.


Examples

This example generates a single polygon from four distinct arcs, creates polygon and line topology and then ungenerates the coordinates into ASCII files using the EXPONENTIAL and FIXED options.  Notice how the Duplicate nodes option affects the output when polygons are used.

The following generate file is used in the Generate to Coverage Wizard to create a box.

ID: 101
X,Y: 0,0
X,Y: 10,0
X,Y: end

ID: 102
X,Y: 10,0
X,Y: 10,10
X,Y: end

ID: 103
X,Y: 10,10
X,Y: 0,10
X,Y: end

ID: 104
X,Y: 0,10
X,Y: 0,0
X,Y: end
ID: end

Here is a list of the coverage’s PAT:

Record     AREA   PERIMETER   BOX#  BOX-ID
1      -100.000      40.000      1       0
2       100.000      40.000      2       0

Here is a list of the coverage’s AAT:

Record FNODE# TNODE# LPOLY# RPOLY# LENGTH BOX# BOX-ID
1          2      1      2      1  10.000    1    103
2          1      3      2      1  10.000    2    104
3          4      2      2      1  10.000    3    102
4          3      4      2      1  10.000    4    101

Listing of a generate file after the coverage’s lines have been ungenerated using the Coverage to Generate tool with the Fixed format option selected:

103
  10.0000000         10.0000000
   0.0000000         10.0000000
END
104

   0.0000000         10.0000000
   0.0000000          0.0000000
END
102
  10.0000000          0.0000000
  10.0000000         10.0000000
END
101
   0.0000000          0.0000000
  10.0000000          0.0000000
END
END

Listing of a generate file after the coverage’s lines have been ungenerated using the Coverage to Generate tool with the Exponential format option selected:

103
0.1000000E+02         0.1000000E+02
0.0000000E+00         0.1000000E+02
END
104
0.0000000E+00         0.1000000E+02
0.0000000E+00         0.1000000E+02
END
102
0.1000000E+02         0.1000000E+02
0.1000000E+02         0.1000000E+02
END
101
0.0000000E+00         0.1000000E+02
0.1000000E+02         0.1000000E+02
END
END

Listing of a generate file after the coverage’s tics have been ungenerated using the Coverage to Generate tool with the Fixed format option selected:

1         10.0000000          0.0000000
4         10.0000000         10.0000000
2          0.0000000          0.0000000
3          0.0000000         10.0000000
END

Arc: ungenerate poly box box.poly nodes fixed

Listing of box.poly: (Duplicate nodes are written)

Listing of a generate file after the coverage’s polygons have been ungenerated using the Coverage to Generate tool with the Duplicate nodes option checked:

0          5.0000000          5.0000000
10.0000000         10.0000000
10.0000000          0.0000000
10.0000000          0.0000000
 0.0000000          0.0000000
 0.0000000          0.0000000
 0.0000000         10.0000000
 0.0000000         10.0000000
10.0000000         10.0000000
END
END

Listing of a generate file after the coverage’s polygons have been ungenerated using the Coverage to Generate tool with the Duplicate nodes option checked:

0          5.0000000          5.0000000
10.0000000         10.0000000
10.0000000          0.0000000
 0.0000000          0.0000000
 0.0000000         10.0000000
10.0000000         10.0000000
END
END

The following example demonstrates how a simple polygon coverage can be converted to text files for transfer to another mapping system. The Coverage to Generate File tool is used twice: once for polygons and again for tics.

GENCOV-ID   SOIL TYPE   SUITABILITY
1           3AF         23
2           4EF         100
3           6RT         543

The Duplicate nodes option is unchecked and the Fixed format option is chosen for both tics and polygons.

Samples of the two files output by the tool are listed below:

Listing of GENPOLY.FIL:

  1    242777.81   211533.09
237862.53   203392.37
237862.53   203744.28
223343.62   218923.15
223343.62   222271.06
259565.31   222271.06
259565.31   195577.37
253137.66   195577.37
244970.75   203744.28
237862.53   203392.37
END

  2    230527.44   199282.72
223343.62   218923.15
244970.75   203744.28
237862.53   203392.37
237862.53   187410.50
239072.44   186200.56
223343.62   186200.56
223343.62   218923.15
END

  3    243458.37   195199.28
237862.53   203392.37
244970.75   203744.28
253137.66   195577.37
259565.31   195577.37
259565.31   186200.56
239072.44   186200.56
237862.53   187410.50
237862.53   203392.37
END
END

Listing of GENTIC.FIL:

1   223343.600   186200.500
2   259565.300   186200.500
3   223343.600   222271.000
4   259565.300   222271.000
END


Coverage to VPF

Converts an INFO table into a VPF table, or converts an ArcInfo coverage into a VPF coverage or VPF tile.

Notes

The coverage must not have a mask file. Use the Clean tool to remove mask files.

The coverage must have a projection defined or it will not be converted.

A full VPF pathname must be specified with Output VPF dataset.

Pathnames are specified as vpfDatabase\vpfLibrary\vpfCoverage when the Input dataset type is set to Coverage.

Pathnames are specified as vpfDatabase\vpfLibrary\vpfTable when the Input dataset type is set to Table.

If the vpfDatabase or the vpfLibrary directories do not exist, they will be created.

The Output VPF tile will be appended to vvpfDatabase\vpfLibrary\vpfCoverage\ specified by the Output VPF dataset and is only valid when the Input dataset type is set to Coverage.

Projections must match between the library and the coverage being created.

Converting extra tables

Conversion control file format and commands

Related Topics


The coverage or table you want to convert to VPF format.


Choose what type of data to convert.

Coverage – converts a coverage to a vector product format (VPF) coverage that can be referenced to a VPF tile.

Table – converts an INFO table to a VPF table.


A conversion control file lets you define how to convert coverage features and table items to create VPF Standard compliant output. It also lets you add information to the VPF database and library header files. If it does not already exist, you can create it by clicking the adjacent browser button and then clicking Yes to start the Header and Control File Builder.


The VPF tile in the tileref coverage that you assign to the VPF coverage you will create. Specify the VPF tile for your VPF coverage.

NOTE:  A tile reference coverage (which is a polygon coverage) must exist in the target VPF library. Some libraries in a VPF database may be tiled or untiled, but all the coverages in a given library must have the same tiling scheme, defined by a tile reference coverage stored in the library along with the coverages it applies to.


Do you want to convert all files to VPF or only those needed to create a VPF coverage?

Checked – converts all available coverage or table files to VPF format. Use this option if you want to convert the VPF coverage back to ArcInfo format using the VPF to Coverage tool.

Unchecked – converts only those coverage files needed to create a VPF coverage. Use this option if you do not want to convert the VPF coverage back to ArcInfo format. Files such as TIC and LAB are considered extra files, since they are not necessary to make up a VPF coverage.


Yes – converts all available coverage or table files to VPF format. Use this option, if you want to convert the VPF coverage back to ArcInfo format (using the VPF to Coverage tool).


No – converts only those coverage files needed to create a VPF coverage. Use this option, if you do not want to convert the VPF coverage back to ArcInfo format.


Check if you want to create a Feature Index Table.


The VPF dataset you will create.

NOTE: You must specify the full pathname; for example, vpfDatabase\vpfLibrary\vpfCoverage or vpfDatabase\vpfLibrary\vpfTable


Extra Tables

In the default translation of a coverage into a VPF coverage, arcs become edges, polygons become faces, nodes remain nodes. Feature attribute tables become feature tables with a 1:1 relationship with primitive tables. One exception is the annotation TAT, which becomes one primitive table plus as many feature tables as there are annotation subclasses in the coverage. Route and Section tables become unconnected ‘extra’ tables.

Other coverage tables are translated to VPF as extra tables, meaning that the tables are not needed to make up VPF coverages, but should be maintained in order for the VPF to Coverage tool to translate all of the coverage information back into ArcInfo. If there are no VPF tiles, the extra tables are located at the coverage level, otherwise they are located at the tile level. Extra tables that may be generated by the tool are TIC, SEC, RAT, LNK,TRN, ADD and ADDRESS.LST. The naming convention is X_TIC, X_SEC, X_RAT etc.


Conversion control file format

When a coverage is converted, the EXPORT section of the conversion control file may (but is not required to) have three subsections: global commands, primitive commands, and feature commands. Each subsection may contain any number of commands; and each ends with the beginning of the next EXPORT subsection, the beginning of the IMPORT section, or the end of the conversion control file (as indicated by END).

Global Commands

Global commands affect certain characteristics of the VPF tables, coverages, libraries, and databases.

IGNORE <item1>.... {item9} - ignores INFO items during translations. Up to nine items may be given on any one ignore statement. Once an INFO item is ignored, the data will be lost during the translation to VPF, and will not be regained when using VPFIMPORT.

CREATE NARRATIVE <level> <table> <text_file> {textwidth} (description} - converts input ASCII text file into a VPF narrative table.

CREATESPATIALINDEX <CELL | RANGE> : specifies the type of spatial indices that will be created.  RANGE based indices use equations found in Appendix F of the MIL-STD-2402 (page 164), and should be considered the “older” method.  CELL based indices use the equations found in Appendix F of CHANGE NOTICE 1 of the MIL-STD-2402 (page 164), and should be considered the “newer” method.  If the type of spatial index is not specified within a conversion control file, CELL based indices will be created as the default.

SET <table> <column> <value> - sets a VPF table column to a specific value.

SET NARRATIVE <vpf_table> <narrative_name> {level} - specifies a narrative table to be associated with a VPF table.

SET DESCRIPTION <vpf_table> <description> {level} - specifies a description string associated with a VPF table.

SETVDT <vpf_table | Null> <item_name> <info_table> - creates the specified VDT table for the coverage from an INFO lookup file with a predefined format.

SETBYTEORDER <least | most> - sets the byte order for all of the VPF tables converted.

SET NULL <vpf_table> <item> <info_null_value> - allows the user to predefine a VPF null value in ARC/INFO.  For example, the user might define "-9" as a VPF null for a specific item in a specific VPF table upon export.  When exported into VPF, the records with "-9" will be converted to the appropriate VPF null for that item type.

SET COVDESC <description> - specifies the description used for the coverage in the Coverage Attribute Table (CAT).

NOCAT - specifies that this coverage should not be added to the Coverage Attribute Table.

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession. When used in the global section, this command will only work using the TABLE option.

Primitive commands

Primitive commands begin with the PRIMITIVECLASS command, which identifies the VPF primitive type affected by subsequent commands.

PRIMITIVECLASS < CND | END | EDG | FAC | RNG | TXT | EBR | FBR > (respectively, connected nodes, entity nodes, edges, faces, rings, text, edge bounding rectangles and face bounding rectangles).

ITEMBECOMES <item> <column> {col_type) (count} {keytype} {description} {vdt} {thematic_index} {narrative}

IGNORE <item1> {item2}............{item9} - ignores specified columns in the ARC/INFO primitive table when the conversion takes place (IGNORE). (Columns required by VPF cannot be ignored, however.)

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession.

Feature commands

Feature commands begin with the FEATURECLASS command, which identifies the ARC/INFO feature class affected by subsequent commands. This section describes the FEATURECLASS command syntax and functions.

FEATURECLASS <arc_feature_class> {feature_table | IGNORE} {description} {info_table | ONE} - arguments allow you to specify an ARC/INFO feature class to be ignored during conversion; to rename, describe, and specify the INFO table that serves as the source for the VPF feature table; to create complex features; and to force a one-to-one relationship between the features and primitives in the route and region feature classes.

<arc_feature_class> - valid feature classes are: ARC, NODE, POINT, POLY, ANNO.subclass, ROUTE.subclass, REGION.subclass, SECTION.subclass, COMPLEX.  See 'Creating complex features' below for a description of COMPLEX.

{feature_table | IGNORE} - either renames the VPF table to be created or ignores the specified <arc_feature_class> during conversion.

{description} - specifies the description for the VPF feature table.

{info_table | ONE} - specifying an info_table name in this argument creates a VPF feature table directly from the INFO table specified.

ADDCOLUMN <column> <col_type> <count> <keytype> {description} {vdt} {thematic_index} {narrative}

ITEMBECOMES <item> <column> {col_type} {count} {keytype} {description} {vdt} {thematic_index} {narrative} - VPF column definition for an INFO item.

IGNORE <item1> {item2...item3} - ignores INFO items.

GROUPBY <column> - only valid within a FEATURECLASS block when an {info_name} has been specified. When converting, the specified column in the INFO table becomes the ID of the VPF feature. This groups all records with the same value for the column into a single record (a single feature).

JOIN <vpf_table> <info_table>

SCHEMA {table1} {key1} {table2} {key2}

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession.

Creating complex features

Complex VPF features may be created by specifying COMPLEX as the <arc_feature_class>. For example, the command below:

FEATURECLASS COMPLEX airport.cft ‘Airports’ airport.ftr

creates a complex VPF feature table with the name 'airport.cft' and a description of airports from the INFO table airport.ftr.

When COMPLEX is used, defining feature-to-feature and feature-to-primitive relationships is the responsibility of the user. For that reason, FEATURECLASS commands that specify a COMPLEX feature class should be followed by SCHEMA commands and any necessary JOIN commands.


Vector Product Format (VPF) is a U.S. Department of Defense Standard. The National Imagery and Mapping Agency (NIMA) is using VPF for digital vector products developed at a variety of scales. VPF has also been adopted into an international spatial standard as the Digital Geographic Information Exchange Standard (DIGEST).

VPF is a standard format, structure, and organization for large geographic databases that are based on a georelational data model.


Create Centerlines

Creates centerlines (single-lines) for dual-line features, such as road casings, based on specified width tolerances.

The tool is designed to work with fairly regular casings, representing streets. Irregularly shaped features, such as streams and rivers, can produce unsatisfactory results. Create Centerlines derives a single-line, centered inside a casing, based on the given Maximum width and Minimum width. No centerline is created for a dual-line feature wider than the Maximum width or narrower than the Minimum width. Use known casing widths when setting the parameters. Set the Maximum width greater than the known maximum width, since casings usually become wider at intersections. You may have to experiment to find suitable widths.

Two situations require your special attention:

Intended centerlines may not be created.
Create Centerlines does not recognize the intended line pairs in places where many lines run parallel and the distance between them is smaller and skips every other line pair. As a result, not all intended centerlines may be created.

Unintended centerlines may be created.
Create Centerlines does not always differentiate casings from the space between casings, if both their widths are smaller than the specified Maximum width. As a result, unintended centerlines may be created.

Notes

To yield good results, we recommend that the Input coverage has proper topology and complete casings. Use Build or Clean to create proper topology.

If your data contains casings of distinct widths, we recommend that you assign different codes to the features and process them separately with the relevant widths.

Five items added to the AAT are used to store links to the source data and information to support post-editing.

Examples of finished centerlines

Related Topics


The coverage with double lines from which you want to derive centerlines.


Determines if a casing is reduced to a centerline. No centerline is created for a dual-line feature wider than the Maximum width. The value is in coverage units.
Use the actual casing widths as a reference and choose a value that is slightly greater than its maximum width, since casings usually become wider at intersections.


Determines if a casing is reduced to a centerline. No centerline is created for a dual-line feature narrower than the Minimum width. The value is in coverage units.


The coverage you will create.


Five items added to the AAT

The five items added to the Output coverage arc attribute table (AAT) are:

LTYPE – stores the following values:

1 for centerlines;

2 for unused lines and outlines around “complicated” intersections;

3 for partitioned lines.

LL# – stores the left source arc record number.

RL# – stores the right source arc record number.

L-ID – stores the left source arc User-ID.

R-ID – stores the right source arc User-ID.

All five items have the following definition: item width: 4, display width: 5, item type: B.

If the width of the input data is relatively constant and the intersections are simple, a complete centerline result can be produced, that is, LTYPE = 1 for all resulting lines. Otherwise, unused lines (such as a single casing or casings with a width beyond the specified range) and outlines around complicated intersections will be flagged with an LTYPE value of 2 for editing them further. To view an example, click [image].

The centerline process will partition input data that exceeds 500 arcs. Centerlines are created for each partition and then merged. The partition lines will be included in the result with LTYPE = 3 so that you can check the connections along these lines and delete them.

The items LL#, RL#, L-ID, and R-ID are intended to make it easy to relate the resulting centerlines to their source casings. The items will have the value of zero for non-centerline arcs, that is, the arcs with LTYPE values of 2 and 3.


Examples of centerlines created from cased roads


Create COGO Coverage

Creates a new line coverage with COGO attributes or a COGO point coverage. The standard COGO attributes are added to the COGO coverage arc attribute table (AAT) to store curve and two-point line attributes.

Notes

COGO allows you to work with a minimum set of attributes in the AAT. For example, to work with

Two-point lines, you need only the items ANGLE and DISTANCE.

Circular curves, you need only the items ANGLE, DISTANCE, RADIUS, ARCLENGTH, and SIDE.

Spiral curves, you need only the items ANGLE, DISTANCE, RADIUS, ARCLENGTH, SIDE, and RADIUS2.

How to delete unwanted attributes in ArcCatalog.

This tool requires the user to have write permission to the start-up location of the ArcToolbox application. For example, if ArcToolbox is started from a windows shortcut that refers to a network installation of ArcToolbox, set the startup location of the shortcut to refer to a local directory that you can write to, such as “C:\temp”. The tool creates temporary scratch files and uses the start-up location as the workspace to create these scratch files.

Related Topics


Choose the type of COGO coverage you want to create.

Line – creates a COGO line coverage and adds the standard COGO attributes.

Point – creates a COGO point coverage.


Choose the precision for your COGO coverage:

Double – creates a COGO coverage in double precision (14 decimal places).

Single – creates a COGO coverage in single precision (7 decimal places).

Copy from existing coverage – creates a COGO coverage in the same precision as the coverage you choose below.


The coverage whose precision you want to copy.


The coverage you will create.


The standard COGO attributes are:

ITEM NAME   WIDTH   OUTPUT   TYPE
ANGLE          10      10      C
DISTANCE        8       8      C
RADIUS          8       8      C
DELTA          10      10      C
TANGENT         8       8      C
ARCLENGTH       8       8      C
SIDE            1       1      C
RADIUS2         8       8      C
TANGENT2        8       8      C

ANGLE - the direction of two-point lines or the chord direction of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves.

DISTANCE - the length of two-point lines or the chord length of circular curves and spirals. This item is needed when working with two-point lines, circular curves, and spiral curves.

RADIUS - the circular curve radius or the first radius of a spiral. This item is needed when working with circular curves and spiral curves.

DELTA is the delta angle of a circular curve or spiral. This item is needed when working with circular curves.

TANGENT - the tangent length of a circular curve or the first tangent length of a spiral.

ARCLENGTH - the arc length of a circular curve or spiral. This item is needed when working with circular curves and spiral curves.

SIDE - the right or left side where the radius point for curves or radius points for spirals are located with respect to the circular curve or spiral. This item is needed when working with circular curves and spiral curves.

RADIUS2 - the second radius of a spiral. This item is needed when working with spiral curves.

TANGENT2 - the second tangent length of a spiral.


Create Polygon Labels

Creates label points for polygons that have no labels and assigns each a User-ID. The Build or Update IDs tool must be run afterwards to synchronize User-IDs (see Required post-processing below.)

The ID base value provides the starting point for creating the label point User-IDs. The specified value will be the User-ID for the first polygon encountered which has no label point. User-IDs are then incremented by one for each subsequent polygon having no label point. Specifying an value of 0 will cause the creation of new labels for all polygons, where each User-ID will equal the polygon’s internal number minus one.

The tool does not check whether the User-ID number to be assigned to a new label point already exists for a previous polygon label point. This could result in the generation of duplicate User-IDs, depending on the value specified. (Duplicate User-IDs are allowed in ArcInfo but not recommended.) For example, existing attributes may be different for polygons which have the same User-ID.

Here are a few recommendations for specific cases:

If you are creating labels for a new coverage which does not yet contain attributes, use a value of 0 and then run the Build tool.

If you are creating new label locations for an existing coverage which already contains unique User-IDs and associated attributes, use a value of 0 and then run the Update IDs tool. This ensures that any additional attributes which are stored in related files using the polygon’s User-ID will not be lost or mixed up.

If you are creating new label locations for only some polygons in an existing coverage, specify a value which is greater than the highest existing User-ID. This ensures that the new label points that are generated for any unlabeled polygon will have unique values. Then use Build to assign these new User-IDs to the unlabeled polygons. In this case, all of the previously existing User-IDs and their associated feature attributes will be maintained.

Notes

If the specified ID base value is negative, all new User-IDs will start with the specified value and be decremented by one for each new label point.

Required post-processing

Once Create Polygon Labels has been run on a coverage, the new label points and their User-IDs are stored in the coverage LAB file. However, any previously existing User-IDs in the polygon attribute table (PAT) of this coverage have not yet been updated. This creates a temporary situation where the new User-IDs in the LAB file are not equal to the old User-IDs in the PAT. To synchronize the User-IDs, you must use one of these tools:

Update IDs - changes the label point User-IDs to be equal to the User-IDs stored in the PAT.

Build - changes the User-IDs stored in the PAT to be equal to the label point User-IDs.

Related Topics


The coverage to which you want to add label points.


The smallest User-ID value to be assigned to new label points. We recommend the following:

If you are creating labels for a new coverage which does not yet contain attributes, use a value of 0 and then run the Build tool.

If you are creating new label locations for an existing coverage which already contains unique User-IDs and associated attributes, use a value of 0 and then run the Update IDs tool. This ensures that any additional attributes which are stored in related files using the polygon’s User-ID will not be lost or mixed up.

If you are creating new label locations for only some polygons in an existing coverage, specify a value which is greater than the highest existing User-ID. This ensures that the new label points that are generated for any unlabeled polygon will have unique values. Then use the Build tool to assign these new User-IDs to the unlabeled polygons. In this case, all of the previously existing User-IDs and their associated feature attributes will be maintained.


The highest existing User-ID value is shown to help you determine what to put into ID base value. We recommend that you use an ID base value higher than the highest existing User-ID when you are creating new label locations for only some polygons in an existing coverage. This will ensure that the new label points that are generated for any unlabeled polygon will have unique values. See the help file for more information.


Create Thiessen Polygons

Converts Input coverage points to a coverage of Thiessen proximal polygons. Thiessen polygons have the unique property that each polygon contains only one input point, and any location within a polygon is closer to its associated point than to the point of any other polygon.

To ignore close points, specify a Proximal tolerance. For point coverages with an automation scale between 1:10,000 and 1:100,000, try a tolerance between 1.668 ft (0.508 m) and 16.620 ft (5.080 m).

Notes

Data model content inherited by the output

How Thiessen polygons are constructed

Related Topics


How Thiessen polygons are constructed

1	The Input coverage points are scanned left-to-right, top-to-bottom. Points closer than the chosen Proximal tolerance to previously scanned points are ignored.

2	The remaining points are triangulated into a Triangular Irregular Network (TIN) that conforms to the Delaunay criterion.

3	The perpendicular bisectors for each triangle edge are constructed to form the edges of the Thiessen polygons; their intersections become the polygon vertices.

4	The input point locations become label points locations.


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Items from the point attribute table

Tics

Projection file


The point coverage you want to convert to Thiessen polygons.


Specify a Proximal tolerance to ignore close points.

For point coverages with an automation scale between 1:10,000 and 1:100,000, try a tolerance between 1.668 ft (0.508 m) and 16.620 ft (5.080 m). Its unit of measure is that of the Input coverage.

The default tolerance is 1/10,000 of the width or height of the bnd, whichever is greater.


The Thiessen polygon coverage you will create.


Create Tin Wizard

Creates a tin surface model from multiple input sources including point, line and polygon coverages, and points and breaklines in x,y,z generate input files.

Notes

The coordinate precision of the output tin is always double precision.

Related Topics


Weed tolerance

Weed tolerance is the generalization tolerance used to reduce the number of vertices in the input linear features. Arcs typically contain more vertices than are needed to accurately represent a surface. The Create Tin Wizard ignores vertices if they are within the weed tolerance of other vertices on the same arc. Nodes are always retained. Weeding is not done between arcs, or to arcs that have the Nodata value as their z-value. The value for each input defaults to 1/1000 of the greater of its x or y extents.


Specify a Z-value

Specify a Z-value constant – the same elevation value is applied to all Input coverage features. A value of -9999 is interpreted as Nodata.

Choose a Z-value item – the name of the numeric item in the feature attribute table or a related table containing the surface z-values. This item can be different for each Input coverage. In the case of barrier features, the z-values can be set to any value, including the Nodata value -9999. The default item name is SPOT.

If Z-value item is disabled, then there is no attribute table for the feature class that you chose on the previous panel.


Coverage surface features

Choose a surface type keyword

The keyword specifies that every Input coverage feature will be processed as the same specified surface feature type. The default is Mass.

Surface       Numeric      Acceptable coverage
 type          value        feature classes
keyword                    Point   Line  Poly

Ignore            0          x       x     x
Mass              1          *       *     *
Softline          2                  x     x
Hardline          3                  x     x
Softreplace       4                        *
Hardreplace       5                        *
Softclip          6                        x
Hardclip          7                        x
Softerase         8                        x
Harderase         9                        x
Barrier          10                  x

* Nodata z-values are not acceptable for these surface feature types in coverages. Softreplace and Hardreplace features must have valid z-values.

Choose an item to represent the surface feature type

Choose the numeric item from the feature attribute table that contains surface feature type values. SFTYPE is the default surface feature type item name. If an invalid surface feature type value (other than 0 to 10) is discovered during processing, the Create Tin Wizard will halt without building the tin.


Refine the set of coverage features used to define the Tin

Unchecked – every Input coverage feature is used to build the tin.

Checked – creates a subset of Input coverage features with either a logical expression or a Selection file. The results of the logical expression or the contents of the selection file are used to select the features that will be used to build the tin.


Proximal tolerance

The proximal tolerance is used to eliminate duplicate points or points that fall within the specified distance of other points. This tolerance is also applied to all linear feature vertices input as Mass points. The proximal tolerance is set to the greater of two values: the computer’s machine precision or the value you enter.

Z-factor

The Z-factor is the number of ground units in one surface z-unit. The input z-units are multiplied by the specified Z-factor to adjust the Output tin z-units to another unit of measure.

When the Z-factor is set to 1, the wizard does not standardize the output z-units, and the input z-units are maintained in the Output tin.


Generate files

A generate file is an ASCII file that contains x,y coordinates and z-values for point or line features. Each generate input file must contain a single class of features, either Point or Line, and must be space or comma delimited.

All generate file features to be included in the tin must have z-values. If you cannot provide a z-value for a generate file feature, assign it a surface feature type of 0, for Ignore; the feature will be bypassed as the Create Tin Wizard reads the file.

Generate input files can be used to input photogrammetric data gathered from stereoplotters. The coordinate data should be written to Point and Line files containing feature IDs and x,y,z coordinates. The x,y coordinates and z-values can be expressed as integers, or single or double precision floating point values. The x,y coordinates for the Output tin are stored in double precision. The z-values are stored in single precision. Descriptive attributes can be input in separate CODE attribute files containing feature IDs and feature attributes.

Point generate files

POINT input files contain the feature ID and x,y,z coordinates for point features. The format for generate files containing points is:

ID,X,Y,Z
...
END

The end of the file is indicated with the END keyword.

A generate file containing points is shown below. The ID values must always be 1 unless the ID is used as the index to the <generate file>.CODE file to look up surface feature type values. An ID value of 1 indicates a Mass point.

1,234.065,837.123,125.845
1,735.774,729.345,93.739
1,840.934,385.700,157.037
1,385.888,286.602,25.764
END

Special Note: Some unformatted PRINT statements in FORTRAN have been found to add unrecognizable characters to generate input files. These extra characters may cause the file to be unreadable by the Create Tin Wizard. For best results, use formatted I/O.

Line generate files

Line input files contain the feature ID, followed by the x,y,z coordinates for each vertex in the file. The ID may be used as the surface feature type item, or as an index to the <generate file>.CODE table to look up surface feature type values. Each line feature must have at least two, and no more than 20,000, vertices. Here is the general format for LINE input files:

ID
X,Y,Z
...
X,Y,Z
END
END

The end of each arc is indicated with the END keyword, and the end of the file is indicated with a second END keyword.

Every Replace, Clip and Erase polygon feature must be formed by one non-intersecting topologically closed arc. In other words, the beginning and ending nodes must have the same x,y coordinate and z-value. If a Replace, Clip or Erase feature is discovered that is not topologically closed, the Create Tin Wizard ends without building a tin.

Every vertex of a Replace feature must have the same z-value.

A generate file containing one Softline breakline (ID=2) and one Hardclip polygon (ID=7) is shown below. Note that the Hardclip polygon feature is topologically closed in the x,y and z coordinates.

2
2 3 5
4 3 6
4 6 7
END
7
7 7 4
7 2 4
1 1
3.5
1 7 3
7 7 4
END
END

Weed tolerance

Weed tolerance is the generalization tolerance used to reduce the number of vertices in the input linear features. Arcs typically contain more vertices than are needed to accurately represent a surface. The Create Tin Wizard ignores vertices if they are within the weed tolerance of other vertices on the same arc. Nodes are always retained. Weeding is not done between arcs, or to arcs that have the Nodata value as their z-value. The value for each input defaults to 1/1000 of the greater of its x or y extents.


Generate file surface features

Choose a surface type keyword - every generate file feature will be processed as the same specified surface feature type.

Surface       Numeric    Acceptable generate file
 type          value             types
keyword                       Point   Line

Ignore            0             x       x
Mass              1             *       *
Softline          2                     *
Hardline          3                     *
Softreplace       4                     *
Hardreplace       5                     *
Softclip          6                     *
Hardclip          7                     *
Softerase         8                     *
Harderase         9                     *
Barrier          10                     x

* Nodata z-values are not acceptable for these surface feature types in generate files. Therefore, you must provide a valid z-value or code the feature as an Ignore feature.

Use the feature ID - choose a numeric item from the <generate file>.CODE INFO table, or a related table containing the surface feature type numeric values. It is not necessary to establish a relate between the generate file and the <generate file>.CODE INFO table; this relate is automatically established by the Create Tin Wizard. If no item is specified, each feature’s ID is interpreted as the item by default. If an invalid surface feature type code (other than 0 to 10) is encountered during processing, the wizard will halt without building the tin.


Datasets

The Create Tin Wizard allows you to combine data from coverages and generate files to build a tin surface model. When you Add coverage… or Add Generate file…, you navigate through several panels to specify parameters for that particular input source. When you get back to this panel you can choose another input source or go on with Next.

You may Edit… the parameters of a dataset, or Delete it entirely by first highlighting the Dataset name in the textbox, then clicking the appropriate button.


Create VPF Tile Topology

Creates cross-tile topology for all tiled coverages in a Vector Product Format (VPF) database library, or topology for an individual tile in a VPF library.

The tool is used for post-processing of Coverage to VPF output. For efficiency purposes we recommend that you build cross-tile topology only after you have converted all coverages in your VPF library from ArcInfo to VPF format.

The tool provides two options, one for each version of the VPF standard:

For the 1993 version, Create VPF Tile Topology does not handle the situation where more than two edges coincide along a tile boundary. It is impossible to assign left-face and right-face values to each edge.

For the 1996 version, cross-tile topology must be created on the connected nodes. In order for cross-tile to work correctly, the 'first_edge' column in the connected node tables must be a Triplet type.

Because this tool makes modifications to the primitive file in your VPF database, it is important to fully understand the requirements of the VPF data before creating cross-tile topology. The most important things to remember about creating 1996 cross-tile topology are the following:

If an edge touches a tile boundary, the point at which it touches must be a node.

All nodes that exist on a tile boundary must exist in the adjacent tile, if such tile exists.

All edges that are coincident with an interior tile must exist in both tiles.

All tile boundary edges must be totally straight edges.

  Learn more about VPF tile topology

Related Topics


The VPF library for which you want to create cross-tile topology.


The number of Decimal places used to match node coordinates at tile boundaries. The default is 4 places. The more Decimal places used, the smaller the search tolerance.


Choose the version of the VPF Standard you want to use to create cross-tile topology:

1993 version – creates cross-tile topology based on the September 30, 1993 version of the VPF Standard (MIL-STD-2407).

1996 version – creates cross-tile topology based on the June 28, 1996 version of the VPF Standard (MIL-STD-2407).


Choose how you want to create topology:

Checked – creates topology for all coverages in the VPF library.

Unchecked – lets you specify a single VPF coverage and creates topology only for it.


The single VPF coverage for which you want to build topology.

NOTE: All available VPF coverages in the VPF library are listed.


VPF Tile Topology

Military Standard MIL-STD-2407 (1993 and June 28, 1996) specify details on VPF tile topology. The 1996 version refines the definition of cross-tile topology as described in the 1993 version.

The VPF Military Standard requires that primitives such as edges and faces between tiles are connected. The Coverage to VPF tool converts coverage data one tile at a time. Once all tiled data has been converted, the Create VPF Tile Topology tool is used to build cross-tile topology.

The edge table for a tiled VPF coverage contains ‘right_edge’ and ‘left_edge’ columns that are defined as triplet ID data types. If the coverage also contains faces, the edge table will have triplet ID ‘right_face’ and ‘left_face’ columns. The first section of a triplet ID column is for internal topological relationships. It contains an identifier that links one primitive to another primitive within one tile. The second and third sections of a triplet ID column are for external (cross-tile) topological relationships. The second element holds an identifier to an adjoining tile, while the third element stores an identifier to a connecting primitive in that adjoining tile.

When a VPF coverage is converted with the Coverage to VPF tool, the second and third values in the triplet ID columns in the edge tables are initialized to 0. The Create VPF Tile Topology tool updates these values if a connecting primitive was found in the adjoining tiles.

The 1996 Standard introduces cross-tile topology on the connected node table. Any node that occurs on a tile boundary will have a triplet ID populated with an internal ‘first_edge’, as well as an external ‘first_edge’ that occurs in the adjoining tile.


Vector Product Format (VPF) is a U.S. Department of Defense Standard. The National Imagery and Mapping Agency (NIMA) is using VPF for digital vector products developed at a variety of scales. VPF has also been adopted into an international spatial standard as the Digital Geographic Information Exchange Standard (DIGEST).

VPF is a standard format, structure, and organization for large geographic databases that are based on a georelational data model.


Cross-reference of ArcInfo commands embedded in ArcToolbox
Cross-reference list of ArcInfo commands embedded in Arc Toolbox

Arc commands	Tool names

A

ADD	Add from ASCII

ADDCOGOATT	Add COGO Items

ADRGGRID	ADRG to Grid

APPEND	Append Wizard

ARCCOGO	Calculate COGO Attributes

ARCDFAD	Coverage to DFAD

ARCDIME	Coverage to DIME

ARCDLG	Coverage to DLG

ARCDXF	Coverage to DXF

ARCIGDS	Coverage to IGDS Wizard

ARCIGES	Coverage to IGES

ARCMOSS	Coverage to MOSS

ARCROUTE	Line Coverage to Route

ARCSHAPE	Coverage to Shapefile

ARCSLF	Coverage to SLF

ASCIIGRID	ASCII to Grid

AREAQUERY	Extract Wizard

B

BUFFER	Buffer, Buffer Wizard

BUILD	Build

BUILDINGSIMPLIFY	Simplify Buildings

C

CENTROIDLABELS	Centroid Labels

CENTERLINE	Create Centerlines

CLEAN	Clean

CLIP	Clip

CREATECOGO	Create COGO Coverage

CREATELABELS	Create Polygon Labels

CREATETIN	Create Tin Wizard

CUTFILL	Cut & Fill

D

DBASEINFO	dBASE to INFO

DBMSINFO	DBMS to INFO

DEFINE	Define Table

DEMLATTICE	DEM to Grid

DFADARC	DFAD to Coverage

DIMEARC	DIME to Coverage

DISSOLVE	Dissolve

DLGARC	DLG to Coverage Wizard

DTEDGRID	DTED to Grid

DXFARC	DXF to Coverage Wizard

E

ELIMINATE	Eliminate

ERASE	Erase

ETAKARC	Etak to Coverage

EXPORT	Export to Interchange File

F

FINDCONFLICTS	Find Building Conflicts

FLOATGRID	Floating Point Data to Grid

FREQUENCY	Frequency, Statistics Wizard

G

GENERALIZE	Generalize Lines

GENERATE	Generate to Coverage Wizard

GRIDASCII	Grid to ASCII

GRIDFLOAT	Grid to Floating Point Data

GRIDIMAGE	Grid to Image

GRIDLINE	Grid to Line Coverage

GRIDPOINT	Grid to Point Coverage

GRIDPOLY	Grid to Polygon Coverage

H

I

IDEDIT	Update IDs

IDENTITY	Identity, Overlay Wizard

IGDSARC	IGDS to Coverage Wizard

IGDSINFO	IGDS to Coverage Wizard

IMAGEGRID	Image to Grid

IMPORT	Import from Interchange File

INFODBASE	INFO to dBASE

INFODBMS	INFO to DBMS

INTERSECT	Intersect, Overlay Wizard

J

JOINITEM	Join Tables

K

L

LATTICECONTOUR	Contour Wizard

LATTICEDEM	Grid to DEM

LATTICETIN	Grid to Tin

LINEGRID	Line Coverage to Grid

LOTAREA	Calculate Legal Area

M

MAPJOIN	Append Wizard

MOSSARC	MOSS to Coverage

N

NEAR	Near

O

P

POINTDISTANCE	Point Distance

POINTGRID	Point Coverage to Grid

POINTNODE	Point Node

POLYGRID	Polygon Coverage to Grid

POLYREGION	Polygon Coverage to Region

PROJECT	Project Wizard

PROJECTCOMPARE	Define Projection Wizard

PROJECTCOPY	Define Projection Wizard

PROJECTDEFINE	Define Projection Wizard

PULLITEMS	Copy Items

Q

R

REGIONBUFFER	Buffer Regions, Buffer Wizard

REGIONCLASS	Line Coverage to Region

REGIONCLEAN	Clean Regions

REGIONDISSOLVE	Dissolve Regions

REGIONPOLY	Region to Polygon Coverage

REGIONQUERY	Extract Wizard, Query Regions

RENODE	Renumber Nodes

RESELECT	Extract Wizard, Select

S

SDTSEXPORT	Export to SDTS

SDTSIMPORT	Import SDTS Wizard

SHAPEARC	Shapefile to Coverage

SLFARC	SLF to Coverage

SPLIT	Split

STATISTICS	Statistics Wizard, Summary Statistics

T

THIESSEN	Create Thiessen Polygons

TIGERARC	TIGER to Coverage Wizard

TINARC	Tin to Coverage

TINCONTOUR	Contour Wizard

TINLATTICE	Tin to Grid

TINVRML	Tin to VRML

TRANSFORM	Transform

U

UNGENERATE	Coverage to Generate File

UNION	Overlay Wizard, Union

UPDATE	Update

V

VISIBILITY	Visibility

VOLUME	Volume

VPFEXPORT	Coverage to VPF

VPFIMPORT	VPF to Coverage

VPFTILE	Create VPF Tile Topology

W

X

Y

Z


Cut & Fill

Summarizes the areas and volumes of change during a cut-and-fill operation on an area represented by two grids, one before and one after the cut-and-fill operation. It creates a grid and a polygon coverage with volume information describing surface changes.

The Output grid is created by subtracting the After grid from the Before grid. The resulting mesh point z values represent the net change following the cut-and-fill operation. Negative z values indicate regions of the Before grid that have been filled; positive z values indicate cuts.

The Output coverage is a double-precision polygon coverage classified by net change. CF-CODE values in the polygon attribute table identify the type of change:

Net Change        CF-CODE
No change            0
Cut region           1
Fill region          2
NODATA region    -9999

Z-factor is the number of ground x,y UNITS in 1 surface ZUNIT. The input ZUNITS are multiplied by the specified Z-factor to adjust the output ZUNITS to another unit of measure.

Notes

Before execution, Cut & Fill verifies that the Before grid and After grid are coincident. That is, they have the same origin, cell size, and number of cells in x and y. Use the LATTICERESAMPLE command if you need to make the grids coincident.

For topographic surfaces, the ground UNITS should be in the same units of measure as the surface ZUNITS. This ensures that the resulting volumes are meaningful cubic measures (e.g., cubic meters). Tip: First use the LATTICEOPERATE command to convert the surface ZUNITS, or specify a Z-factor in the Cut & Fill tool.

Areas and volumes are calculated on the assumption that the mesh points lie in the center of each cell. Therefore, output polygons representing mesh points lying on the edges of the input grids extend one half of the cell size beyond the grid extents.

The Output coverage has an associated INFO table named <Output coverage>.CF with summary area and volume statistics. A positive BALANCE_VOL value indicates excess material remains after the cut-and-fill operation; a negative value indicates a shortage.

The formula for the volume at a grid point is

How Cut & Fill handles NODATA values

Example

Related Topics


 A cut-and-fill operation is a procedure where the elevation of a surface is modified by the addition or removal of surface material. For example, during the construction of a highway roadbed, material is removed from road sections where the existing surface is too high and deposited as fill in road sections that are too low.


How Cut & Fill handles NODATA values

Areas in either input grid that contain the NODATA value, -9999, produce NODATA cells in the Output grid.

Internal NODATA cells cause island polygons to be formed inside the Output coverage with a CF-CODE of -9999. NODATA points on the edge of the Output grid are not included in the Output coverage.

Area statistics in the CF table do not include NODATA areas.


Example

This example shows how the Output coverage and CF table are calculated by Cut & Fill. The mesh point spacing is 10 meters, so each cell represents an area of 100 square meters. Note how the NODATA mesh point on the edge of the input grids is not reflected in the area statements in the CF table.

Listing of REPORT7.CF:

1

CUT_VOL = 3000.000
FILL_VOL = 1800.000
BALANCE_VOL = 1200.000
CUT_AREA = 800.000
FILL_AREA = 400.000
GRADED_AREA = 1200.000
NOT_GRADED = 300.000
TOTAL_AREA = 1500.000


Example (with tool text)

This example shows how the Output coverage and CF table are calculated by Cut & Fill. The mesh point spacing is 10 meters, so each cell represents an area of 100 square meters. Note how the NODATA mesh point on the edge of the input grids is not reflected in the area statements in the CF table.

Before grid = terrain
After grid = design7
Z-factor = 1
Output grid = project7
Output coverage = report7

Listing of REPORT7.CF:

1

CUT_VOL = 3000.000
FILL_VOL = 1800.000
BALANCE_VOL = 1200.000
CUT_AREA = 800.000
FILL_AREA = 400.000
GRADED_AREA = 1200.000
NOT_GRADED = 300.000
TOTAL_AREA = 1500.000


The grid with surface elevation values before the cut-and-fill operation.


The grid of the same extent as Before grid, with elevation values after the cut-and-fill operation.


The Z-factor states how many ground units in your surface equal one elevation- or z-unit. It is possible that the ground units are in meters and its elevation units are in feet.

To get a meaningful and correct difference calculation, enter a Z-factor to convert the elevation units of your input surface to the same unit of measure as its ground units. For example, the Z-factor to convert feet to meters is 0.3048, and from meters to feet is 3.2808.


The grid that shows the net change in the surface during the cut-and-fill operation.


The coverage with polygons classified as cut or fill areas.


dBASE to INFO

Converts a dBASE data table to an INFO table.

Notes

The tool uses the dBASE field names for the default INFO item names. When a dBASE file has field names that are not valid INFO item names, the tool converts the field names into valid INFO item names.

The data types between INFO and DBASE differ and therefore it is necessary to map dBASE data type into the appropriate INFO data type. Applying the Define mapping option and explicitly defining the INFO item type for each dBASE field can override the default data type mapping, displayed in the following table.

Default dBASE to INFO data type conversion:

dBASE field types                  ArcInfo item types

                                  Type  Width  Output  Dec
Character       <expC> (n)         C      n       n
Numeric         <expN> (n,m)n<=7   F      4       n     m
                n<=7,m=0           B      4       n     -
                n>7                F      8       n     m
Floating Point  <expF>(n,m)n<=7    F      4       n     m
                n<=7,m=0           B      4       n     -
                n>7                F      8       n     m
Date            <expD>             D      8      10
Logical         <condition>        B      2       5
Memo            <expM>             C     10      10

Supported file extensions

Related Topics


The dBASE table you want to convert.


The INFO table you will create.


Choose the data type mapping from dBASE fields to INFO items.

Default mapping - performs the default field-to-item data type definitions.

Define mapping - you explicitly define the definitions of each INFO item converted from the dBASE fields.


DBMS to INFO

Copies an external DBMS table or view into an INFO data file.

This tool does not support remote processing using a Geoprocessing Server.

Notes

For a description of the default DBMS-to-INFO data type mapping, refer to the DBMS specific data type mapping chart.

The tool uses the DBMS column names for the default INFO item names. When a table has column names that are not valid INFO item names, the column names are converted into valid INFO item names. For a discussion of valid INFO item names, refer to ArcDoc>Working with Tables>Using INFO>Defining data files.

INFO date items do not support the time portion of DBMS date fields and are limited in the range of dates supported. DBMS date data types are, by default, converted to INFO character items. To convert DBMS date columns to INFO date items, you must explicitly define an INFO item to be a date data type in the Define mapping dialog.

If the DBMS table contains a binary large object (BLOB) column, then the BLOB data is written as disk files. The INFO character item corresponding to the BLOB column will contain the pathname to the generated BLOB system files. A disk file is created for each BLOB column in each row of the table being converted. Files are created in the output workspace with the following local name format:

<column><number>.<txb | byb>

where

<column> - is the name of the BLOB column in the DBMS table.

<number> - is a unique number, starting from 1, generated for each BLOB in the DBMS table being transferred.

txb - is the file name extension for text BLOBs.

byb - is the file name extension for byte BLOBs.

This tool requires that the Database Integrator (DBI) be installed. DBI is part of core ArcInfo Workstation. If DBI is not installed the tool will produce a “No available databases, contact your DBMS administrator” warning message when this tool is opened.

Supported DBMS

Related Topics


The name of the database containing the DBMS table. The name can not exceed sixteen characters.


The name of the database table to copy. The list displays all tables in the database you have access to.


An SQL select statement used to select a subset of data from the database table. Character column values in a select statement must be wrapped by two single quotes.

Example:

 select state = ‘’California’’


Choose whether to use the default mapping provided by the tool, or to define the column-to-item data type conversion.


The new name for the item in the INFO table.


The width of the INFO item.


The output width of the INFO item.


INFO item data type.


Number of decimal places for decimal data types.


The name of the INFO data file to create.


.The column in the DBMS table to be mapped.


DBMS Supported by Database Integrator (DBI)

  CA-OpenIngres

  Informix

  Oracle

  Microsoft Access

  Microsoft SQL Server

  Sybase


INFO item types

Item type	Internal width 	Description

B(Binary)	1-4 bytes	Number stored as binary integer.

ARC supports whole numbers stored as binary integers (width of 2 or 4 bytes only). The maximum value for width of 2 is 32,767; for width of 4 is 2,147,483,647. The minimum value for width of 2 is -32,768; for width of 4 is -2,147,483,648. No decimal positions are allowed.

C(Character)	1-4096 bytes	Character field. Supports character fields up to 320 wide.

D(Date)	8 bytes	Date field, stored internally as YYYYMMDD.

F(Floating)	4-8 bytes	Number stored in floating-point format.

ARC supports decimal numbers stored in internal floating-point representation (width of 4 or 8 bytes only).  A 4-byte width is single-precision real (approximately 7 digits of precision), and 8 bytes is double precision (approximately 15 digits of precision).

I*(Integer)	1-16 bytes	Integer item stored as 1 byte per digit.

Width from 1 to 16, maximum value possible is 9,999,999,999,999,999. No decimal positions are allowed.

N*(Number)	1-16 bytes	Number with decimal places.

Can have up to 16 digits, including the decimal point and minus sign if the value is negative.

* INFO maintains precision to 14 significant positions.


The length of the DBMS column being defined. This applies to characters and fixed-point numeric types.


The type of the selected DBMS column. Refer to the DBMS specific data type mapping chart found in this tool’s help page for more information.


Data Conversion

  Agreement in data standards
  Standards for data exchange
  The Spatial Data Transfer Standard (SDTS)
  The SDTS and the NSDI
  The Vector Product Format (VPF)

Agreement in data standards

The increased use of GIS technology has created an explosive demand for GIS data and this demand has brought data standards into close focus. The scope of which extends beyond the data itself to areas governing hardware and software, data collection and management, and data storage and transfer.

Standards are a way for us to collectively agree on issues that help reduce the amount of ambiguity that results when there is an abundance of data collection activities and a lack of standardized methods for doing them. When we increase our ability to share information, we effectively reduce costs involved in its acquisition.

Standards allow us to communicate with less confusion or misinterpretation. When we are all using the same terminology we can share information the same way we can share ideas when we speak the same language. One important aspect of standards are standards for data exchange.

Standards for data exchange

There is a different data exchange format for every major digital data product distributed outside its native environment, most of which carry only basic spatial information and minimal attributes. Decades have been spent collecting data and organizing it into comprehensive databases. The investment in data is considerable and the need to disseminate this information is a growing concern that has brought about the development of a very high order of standards for data exchange. Nowhere is this more evident than in the major data producing agencies of the Federal government where the development of a standard way to describe and transfer Federal geographic data products is a government mandate.

Two Federal agencies are the responsible maintenance authorities for what have become national and international standards for data exchange.

The U.S. Geological Survey (USGS) maintains the Spatial Data Transfer Standard (SDTS), a Federal standard used to transfer a variety of Federal data products including DLG, TIGER/Line and GRASS.

The National Imagery and Mapping Agency (NIMA), formerly Defense Mapping Agency (DMA), is the U.S. guardian of the international military standard Digital Geographic Information Exchange Standard (DIGEST). This standard has evolved into a family of exchange standards including VPF, a format for direct access and distribution of NIMA’s vector products including Digital Chart of the World (DCW).

Even though each agency worked in open communication and coordinated their efforts with one another, the resulting standards, though similar, branch off in different directions to meet their users’ needs. While their goals were the same, the client bases they served were different.

The Spatial Data Transfer Standard

The Spatial Data Transfer Standard is a Federal Information Processing Standard developed to accommodate different data models, preserve feature relationships of even the most complex database designs, and provide a mechanism to transfer data dictionaries and metadata for certification and fitness for use.

The SDTS provides an extensive dictionary of standardized geographic, cartographic, geologic, and hydrologic feature attribute terms and definitions.

Because so many types of data are supported in the SDTS, the standard is broken up into subsets of options specific to a particular data type. These subsets are called profiles. Each profile is an approved Federal Information Processing Standard in itself. The only profile supported at Version 7 is the TVP profile for topologic vector data with geometry. A draft version of the raster profile is currently being reviewed and will be implemented in a future release.

Under the guidance of the U.S. Geological Survey, a conformance testing program is currently under way. This program is used to verify the degree to which a product conforms to the SDTS standard. Testing is done on the encoding, decoding, and output transfer modules for each profile. The program will begin soon but was not available to test the Version 7 SDTS converter.

It is important to consider the Version 7 SDTS converter a prototype. Changes in our output transfers and our conversion software may become necessary in order for us to receive product certification for the TVP profile. We plan to participate in the USGS conformance testing program to obtain the acceptance and the assurance that we correctly adhere to the standard.

SDTS and the National Spatial Data Infrastructure

The Federal Geographic Data Committee (FGDC) is responsible for the National Spatial Data Infrastructure (NSDI), a project intended to reduce costly duplication of spatial data management activities. The NSDI consists of individuals of coordinating agencies, both Federal and non-Federal, that will generate or use a national spatial data resource, the technology that will support its use, and the framework that will define and standardize it.

While new standards are being developed for data content, data model, and reference systems, in support of a national data set, the NSDI is promoting the use of existing data standards including those already approved by the FGDC for data transfer and metadata storage.

The SDTS is the transfer standard approved to support the growth of the NSDI. It is flexible, extendible, modular and developed in the spirit of an “open GIS”. It contains a living registry of defined spatial objects and entity terms, documented metadata, and a well organized and structured on-line data dictionary.

Vector Product Format

Vector Product Format (VPF) is a U.S. Department of Defense Standard. NIMA is using VPF for digital vector products developed at a variety of scales. VPF has also been adopted into an international spatial standard as the Digital Geographic Information Exchange standard.

VPF is a standard format, structure, and organization for large geographic databases that are based on a georelational data model.

Related Topics


Converting street network data

The U.S. Bureau of the Census and commercial data suppliers provide digital street network files which can be converted into ArcInfo coverages. These files contain geographic coordinates for linear physical features, such as street centerlines, railroads, streams and political/census area boundaries, as well as addresses and census codes for each feature. ArcInfo conversion programs will create coverages from files in Etak and TIGER format.

The basic feature in street network databases is a line segment representing a linear feature. The boundaries of areas such as census tracts, cities and counties are also represented as line features. Available address ranges and census area codes are stored as attributes for the left and right sides of each line segment (left and right is based on the orientation of the arc looking toward the to-node).

Considerations for converting files

TIGER/Line and Etak data are delivered as ASCII files. You can obtain detailed descriptions of the file contents and format directly from the supplier. Although the files are normally ready for conversion without any editing, their format may not meet the requirements of certain platforms. For example, headers and carriage returns at the end of each record may have to be deleted before running the conversion program. Many data suppliers will deliver the files according to the needs of specific computers.

The conversion programs read each record in each file, create features from the coordinates, and write the attributes to INFO tables. The tables are related to the features by the coverage User-ID so that items can be added to the feature attribute tables using the Join Tables tool, or they can remain as separate tables and accessed by the ArcToolbox relate environment.

Coverage INFO tables are very large and probably contain data unnecessary for your application. You may want to back up the original tables and then delete any unnecessary items.

Each time a new coverage is created, such as when the Project Wizard or Clean tool is executed, the associated INFO tables are also copied. It’s a good idea to delete the previous version of the coverage in order to save disk space, or change the name of the INFO table so it won’t be copied each time.


What are TIGER/Line files?

TIGER is an acronym for Topologically Integrated Geographic Encoding and Referencing system, which is the U.S. Census Bureau’s geographic system to support census programs and surveys. The Census Bureau maintains a digital cartographic database that covers the United States, Puerto Rico, Guam, the Virgin Islands, American Samoa, and the Trust Territories of the Pacific.

TIGER/Line is the line network product of the TIGER system. The cartographic base for these line networks is taken from GBF/DIME where available and from the USGS 1:100,000-scale national map series in all other areas to have continuous coverage. In addition to line segments, TIGER/Line files contain census geographic codes and, in metropolitan areas, address ranges for the left and right sides of each segment. The U.S. Census Bureau provides this information as an extract of the TIGER database in ASCII format on both CD - ROM (compact disk read-only memory) and tape media, in a format that can be read directly by the TIGER to Coverage Wizard.


TIGER/Line format
TIGER/Line file format

  Versions of TIGER/Line files
  Description of record types
  Attribute data in TIGER/Line files

Versions of TIGER/Line files

The U.S. Census Bureau released their first nationwide extract from the TIGER system in February 1989. The first release was a prototype with a slightly different format than subsequent versions of TIGER/Line files and as a result can not be converted by the TIGER to Coverage Wizard.

The TIGER to Coverage Wizard converts all versions released after April 1989. The same basic file format has been maintained throughout all versions released since this date. Each new version has the same number of files as the previous release, plus files containing additional information from the TIGER database.

Regardless of which version you use, all items are named and defined using the most recent 1995 data dictionary provided by the Bureau of the Census.

Unsupported record types

The TIGER to Coverage Wizard does not support Record Types F and G, released with the 1992 School District version. These are temporary record types not found in earlier or subsequent versions.

Coordinate system

The latitude and longitude for all coordinates in the TIGER/Line files are expressed in degrees and decimal fractions of a degree of latitude and longitude. Decimals are carried to six places. TIGER/Line files, 1995 are distributed in NAD83 with the exception of Hawaii which is in NAD27. All earlier version are in NAD27.

Attribute data

Each set of TIGER/Line files contains a great deal of attribute information, which can all be converted with the TIGER to Coverage Wizard. Attributes are stored in INFO tables using item names and definitions that correspond to the field identifiers in the TIGER/Line files, with links to the features they describe. The following is a summary description of this attribute information.

Version numbers
Each file includes a field that identifies the record type and version number. The same version number will appear in all files in a set. This numeric code represents the version of the TIGER/Line file set. The final 1990 Census files, for example, contain version number 03. The U.S. Census Bureau has reserved version numbers 0 through 5,000 for future use but encourages the use of this field outside this range as a means of coding updated features and attributes.

Permanent record numbers
Each line segment is assigned a permanent record number maintained throughout all versions of TIGER/Line files. A permanent record number will be deleted only if the line segment itself changes physically. The U.S. Census Bureau then assigns a new number for that segment and the original number is retired.

TLID, the unique identifier, should be maintained with the coverage (as you would maintain unique User-IDs). Use ID numbers to uniquely identify features and VERSION numbers to record updates and changes to features.

Source codes
Each line and landmark point feature is assigned a code to specify the original source, such as a U.S. Census Bureau 1980 GBF/DIME file or a USGS 1:100,000-scale DLG-3 file. This code appears in record types 1 and 7.

Census feature class codes
Line segments representing physical features are coded based on the USGS classification codes in DLG-3 files. These codes classify features representing roads, railway, power and transmission lines, and hydrographic features. There are various subclasses within each classification.

Street attributes
Includes street address information for select urban areas. The main source of address information is from the 1980 GBF/DIME files. Street attributes include feature name, feature type, prefix and suffix directions, and address ranges. Address ranges may include overlaps, gaps or directional errors.

Feature names may not be consistent with features they represent. One continuous highway may have several segments with different feature names.

Legal and statistical area attributes
Both legal and statistical geographic area codes are stored with each line segment. Legal areas include states, counties, townships, towns, incorporated cities, Indian reservations, and national parks.

Statistical areas are areas used during the census taking where legal areas are not adequate for reporting statistics, such as cases where boundaries change frequently or are poorly defined. Included are census county divisions, designated places, tracts and blocks. The smallest area, blocks, are compact areas usually bounded by streets or other prominently visible physical features.

Geographic area codes will be a primary link between line segments and census data files. These codes are the link to the U.S. Census Bureau’s summary tape files which contain census statistics, such as population and income by census block.

Political boundaries
Election precincts or voting districts may contain a variety of areas including wards, and legislative and election districts. These voting districts were supplied by participating counties of 1990 Census Redistricting program. Voting district codes do not appear in all TIGER/Line files.

Landmarks
Landmark area and point features include schools, military installations, airports, hospitals, mountain peaks, campgrounds, rivers, and lakes.


Supported record types
Description of record types

Record types:  1   2   3   4   5   6    7   8   9    A   C   H   I   P   R   S   Z

Record Type 1 - Basic data record
Contains the basic attribute data and  the beginning and ending points of each line segment. Attribute information includes a permanent record number or TLID, file history, feature type, street address, and legal and statistical area boundaries. The vertices that define the shape of each line segment are in record type 2.This file contains the current geographic area codes and address range and ZIP codes of  each side of each line segement. The attribute information for this record type is stored in the ACODE file.

Record Type 2 - Shape coordinate points
Contains the vertices for the line features. There can be multiple shape point records for each line segment in record type 1. Each record type 2 contains up to 10 coordinate pairs. If the line feature is a straight line defined by two points, there will be no shape coordinates in record type 2. There are no attributes in this record type.

Record Type 3 - Complete chain geographic entity codes
Contains the 1990 Voting District (VTD) codes. The 1995 versions contain no references to the 1980 geographic area codes. Record type 3 also contains current geographic area codes for the 1990 census American Indian areas and the Alaska Native regional Corporations. There is one record for every record type 1. Attributes in this record type are stored in the TYPE3 file.

Record Type 4 - Index to alternate feature names
An index for line segments that have more than one name. The alternate names list is file type 5. Attributes from both type 4 and type 5 records are stored in TYPE5 file.

Record Type 5 - Feature name list
Contains a list of alternate feature names for line features in record type 1 that have alternate names.Records type 4 and 5 are linked together by a feature identifier. Attributes for record types 4 and 5 are stored in the TYPE5 file.

Record Type 6 - Additional address range and zip code data
Contains additional address range and ZIP code information for a line feature that cannot be represented by a single address range. Attributes for this record type are stored in the TYPE6 file.

Record Type 7 - Landmark features
Provides the coordinates for the location of landmark point features and a set of attributes including file history and landmark feature name. Record type 7 also provides attributes and an index to area landmarks in record type 8 through a landmark identifier. Landmark point attributes  are stored in the XCODE file of the landmark cover.

Record Type 8 - Area landmarks
Contains a set of attributes for area landmark features and a polygon identifier that is linked to polygon locations in record type P. Area landmarks attributes are stored in the TYPE8 file

Record Type 9 - Key Geographic Locations
Contains key geographic locations. In versions that do not have this file, KGL are stored in record type 8. Attributes for record type 9 are stored in the TYPE9 file.

Record Type A - Additional polygon and geographic area codes
Provides the area attributes for polygons. The polygons represent areas formed by line segements in records type1 and 2. The left and right area attributes stored on each line segment will match the polygon boundary attributes. There is one record type A for every polygon location in record type P. Attributes for record type A are stored in either the TYPEA or the PCODE file.

Record Type C - List of Geographic Area Codes
Provides a non-hierarchial list of unique geographic codes and their associated names. This is the same information distributed in the GRF-N distributed by the Census Bureau. Information in this record type are stored in the TYPEC file.

Record Type H - TLID History
Provides history for current TLIDs of the basic TIGER/Line features in record type 1. Informaiton for, this record type is stored in the TYPEH file.

Record Type I - Area boundaries
Provides the links to the area boundaries stored as left and right attributes for line features in record type 1. This information is usefull for systems that are not able to build topology because it provides the left and right polygons polygon Ids for each TLID. This informaiton is stored in the TYPEI file..

Record Type P - Polygon location
Provides polygon locations and polygon identifiers for every polygon in the TIGER/Line files defined by the U.S. Census Bureau. This information is stored either in the area point XCODE file or the PCODE file.

Record Type R - TIGER/Line ID record number range
Provides the range of unique TLIDs assigned to a census file in a nationwide schema defined by the U.S. Census Bureau. The range of permanent record numbers applies to each partition.Type R records are stored in the TYPER file.

Record Type S - Polygon codes
Provides space to further identify polygons. This file would be useful for participants in programs returning proposed geographic area codes to the U.S. Census Bureau. Type S records are stored in the TYPES file.

Record Type Z - Zip+4 Codes
Provides the Postal Add-on codes for basic line features in record type 1 and for additional address range records in type 6. The RTSQ is a sequence number used to uniquely identify multiple records for the same line feature. Zip+4 codes are stored in the TYPEZ file.


Using TIGERTOOL
Using the TIGER to Coverage Wizard to convert and process TIGER files

  TIGER to Coverage Wizard processing steps
  Topology and intersection errors
  The Join tables option
  The Project coverages option
  Related tables

TIGER to Coverage Wizard processing steps

The wizard performs the following conversion and processing tasks:

Runs the ArcInfo TIGERARC command using all available options.

Builds output coverages for line, polygon and point.

Merges line features and creates polygon labels.

Provides handling of intersection errors.

Copies and relates attribute tables to feature attributes.

Provides option to join TIGER attributes to feature attribute tables.

Automatically defines the correct datum.

Provides option to project to either UTM or STATEPLANE coordinate system.

Provides a Continue option to continue once intersection errors have been corrected.

Topology and intersection errors

Once the TIGER to Coverage Wizard converts your data, it begins to process the output coverages. It merges the polygon points with line features by combining features from the Output line and area coverage with the Output area point coverage and then builds line and polygon topology for the merged coverage.

TIGER data is normally topologically correct, but can contain intersection errors. An intersection error occurs when two line features overlap without intersecting at a node, usually because the shape record that defines the shape of the line feature is missing. The ensuing two point arc may cross over features that the shaped arc would not.

Polygon topology must be present to fully process TIGER data. If an intersection error is detected when topology is being built, polygon topology will not be created and the wizard will issue a message and stop processing.

You must correct any intersection errors before the wizard can continue. To make corrections without running the Clean tool, run the utility AML that the TIGER to Coverage Wizard writes when it detects an intersection error. The AML, zoom_inter.aml, written to the location of your TIGER dataset, will start up an ArcInfo ArcEdit session. The AML will zoom in on the location where there is an error, and provide a display environment that will assist you in determining the nature of the error and how best to correct it.

The wizard does not run the Clean tool, even though it will add intersections and build topology, because the left and right geographic area codes associated with the intersecting features may no longer be valid and there would be no indication that errors were introduced into your dataset.

If you quit ArcEdit after you have corrected the intersection error, zoom_inter.aml will save your changes. You may now run the TIGER to Coverage Wizard. After you enter the TIGER dataset, the wizard will ask if you want to continue, assuming you have corrected the intersection error. If you are running the wizard on more than one dataset in the same workspace, make sure you move or rename the zoom_inter.aml so that the wizard will not overwrite it each time it executes and discovers an intersection error.

The Join tables option

The Join the tables to the coverage's feature attribute tables option will join the basic line, area, and landmark point features to their feature attribute tables. This makes display and query easier and is recommended for simpler applications.

The Join option will join the following tables:

Attribute Table	JOIN Item	JOIN table
COVER1.AAT	Cover-ID	COVER1.ACODE
COVER1.PAT	Cover-ID	COVER1.PCODE
COVER3.PAT	Cover-ID	COVER2.XCODE

TIGER data contains very large attribute tables that can sometimes slow down ArcInfo processes. By default, the wizard will join attribute tables to feature attribute tables.

The Project coverages option

You can specify either UTM or State Plane coordinate systems for your output coverages. If this option is not used, the projection for each coverage will be defined as GEOGRAPHIC. The wizard will define the datum using the version number read from the TIGER/Line file. Datasets earlier than 1995 are in NAD27 and those released in 1995 or later are NAD83, with the exception of Hawaii which is only in NAD27.

Related tables

An ArcInfo relate environment is defined and stored in a table. The table name is the same as the Output polygon and line coverage with a .REL extension. Use the ArcToolbox Relate Manager to activate stored relates.

The wizard redefines all occurrences of items CENID and POLYID as CENPOLID, and all occurrences of TLID and RTSQ as TLIDSQ. This is done to ensure related features will be uniquely identified.

The following shows the relationship that is established between all tables that the wizard can create. Each associated INFO table is sorted on the relate item, the relate type is ORDERED and the relate name is the same as the related table name.

Attribute Table	Relate Item	Related tables	Relate name
Polycov.AAT	Cover-ID TLID TLID TLID TLID TLID TLIDSQ	COVER1.ACODE COVER1.TYPE3 COVER1.TYPE5 COVER1.TYPE6 COVER1.TYPEH COVER1.TYPEI COVER1.TYPEZ	ACODE   * TYPE3 TYPE5 TYPE6 TYPEH TYPEI TYPEZ
Polycov.PAT	Cover-ID CENPOLID CENPOLID CENPOLID	COVER1.PCODE COVER1.TYPE8 COVER1.TYPE9 COVER1.TYPES	PCODE    * TYPE8 TYPE9 TYPES
Landmark.PAT	Cover-ID	COVER2.XCODE	XCODE    *

* not present if the Join option is used.

Polycov is the Output polygon and line coverage

Landmark is the Output point coverage (landmark features) coverage


Etak MapBase
Etak MapBase files

Etak’s MapBase is a digital street centerline map product that is similar in content to the GBF/DIME format used by the U.S. Census Bureau. Each record represents a single linear feature with addresses and political, census, and ZIP code boundary information. Etak has also included road class designations and, in some areas, major landmark features.

Further details about files and data can be obtained directly from Etak.

Etak file features

There are four possible types of Etak features.

DIME or D types. If the feature type is D, an arc is created along with a corresponding ACODE record. The coordinates are stored in latitude-longitude decimal degrees.

Alternate address or A types. Each A record contains an alternate address record for an arc. These records are written to the ACODE file, and are useful for building address coverages for ArcInfo geocoding.

Shape features or S types. Shape records are used to add vertices to the arcs. The coordinates for these features are in latitude-longitude decimal degrees.

Landmark or L types. If the feature type is L and a Landmark coverage was specified, then a point feature is created along with an associated PCODE record.

Etak files also have records with a C type, which is the copyright statement at the beginning of the file. The Etak to Coverage tool ignores these records, so they do not have to be deleted.

Attributes associated with arcs in the Etak file are used to generate a coverage ACODE file. Attributes associated with polygons in the Etak file are also contained in the cover.ACODE file and can be associated with each polygon using each arc’s left-right polygon identifiers.

Attributes associated with landmark point features are stored in a PCODE file, and related to the point coverage by the User-ID.


Steps for converting Etak files

  Step1: Run Etak to Coverage tool
  Step2: Project coordinates
  Step3: Create topology
  Step4: Project and build Landmark
  Step5: JOIN attributes

Step 1:  Use the Etak to Coverage tool to convert the Etak files

The ETAK to Coverage tool creates a coverage TIC, BND and ACODE file. A PCODE file is also created if a Landmark coverage is specified and if the Etak file contains any records with landmark feature type. The ACODE file contains all of the arc attributes plus the arc User-ID; the PCODE file contains attributes associated with landmarks.

At this time, you may want to check the BND file of the coverage in the Arc Catalog. If the coordinates look incorrect, plot the arcs in ArcInfo’s ArcEdit. If there are stray arcs, the coverage TICs and BND will extend to these invalid arcs. Delete these incorrect arcs before continuing.

Step 2:  Project the latitude and longitude coordinates to a suitable planar coordinate system

Use the Project Wizard to project the coverage to UTM, State Plane or any other planar reference system.

Step 3:  Create topology

Remember to assign unique User-IDs to any new arcs.

If only line features are needed, use the Clean tool with Feature class set to Line. This will identify intersections as well as build an AAT.

Alternatively, to build both polygons and arcs, begin by using the Clean tool with the Poly option. Then create label points for each polygon and update the PAT with the new label points using the Create Polygon Labels tool. After building the polygon coverage, create arc topology using the Build tool with Feature class set to Line.

Note: Remember that each time a new coverage is created, the ACODE file is also copied. You can delete the previous version of the coverage or change the name of the ACODE file so it will not be copied each time.

Step 4:  Project and build the landmark coverage (optional)

If a Landmark coverage was created, it is necessary to project these points into the same projection as the line coverage and build the point features using the Build tool with Feature class set to Point.

Step 5:  Add attributes to the AAT from the ACODE file (optional)

If you want to add attributes from the ACODE file to the coverage AAT, and attributes in the PCODE file to the PAT, you can use the Join Tables tool.


Converting AutoCAD data

Converting an AutoCAD drawing to an ArcInfo coverage first requires the creation of a DXF (Drawing Interchange File) or IGES (Initial Graphics Exchange Standard) file. An AutoCAD DXF file can be produced in either ASCII or binary format using the AutoCAD command DXFOUT. The AutoCAD command IGESOUT produces IGES format files. (Other custom software may also be available that writes DXF format files.)

Of these two options, converting an IGES file to ArcInfo format converts graphics well, but has some limitation converting text, block and attribute entities. For details on converting between ArcInfo coverages and IGES files, refer to the help reference for the Coverage to IGES tool. Creating an ArcInfo coverage from a DXF file allows the most flexibility and minimizes the processing required, once the ArcInfo coverage has been created. This section focuses on the DXF conversion.


IGES and DXF data structure
DXF data structure

AutoCAD Drawing Interchange File (DXF) is the standard interchange format used by most CAD systems. The DXF to Coverage Wizard wizard will read all versions of the AutoCAD DXF ASCII file format, but can only read the optional binary format for AutoCAD Releases 10 to 12.

For information regarding the DXF file format, refer to an AutoCAD reference book such as:

Jones, Frederic H. and Lloyd Martin. The AutoCAD Database Book: Accessing and Managing CAD Drawing Information, Second Edition. Chapel Hill: Venetian Press, 1988.

In general, the DXF data structure is composed of a series of related layers, with each layer containing one or more drawing elements or entities.


AutoCAD terminology

Before proceeding with the DXF conversion, you should be familiar with each of the following terms.

AutoCAD drawing - a single file containing information that describes a graphic image.

Entity - a defined AutoCAD drawing element that can be put into a drawing with a single command (see below). When converted to ArcInfo format, each entity becomes a single coverage feature.

Arc - a partial circle.

Block - a set of entities grouped together into a compound object.

Circle - a circle.

Line - a straight line segment.

Point - a point location.

Polyline - a connected sequence of line and arc segments that can also be any specified width.

Shape - a special entity defined using lines, arcs and circles Shapes are entered into a drawing at a point location.

Solid - a quadrilateral or triangular section that can be solid filled.

Text - a character string that can have a variety of characteristics.

Trace - a straight line segment that can be any specified width.

3DLine - a line type entity that includes z values.

3DFace - a solid type entity that includes z values.

Insert - describes the position at which a previously defined block was inserted in an AutoCAD drawing. Inserts can be converted as the position point or expanded into the block annotation and arc features.

Layer - a grouping of a portion of the entities of a drawing. Multiple layers can be defined for one drawing. The characteristics of a layer are globally applied to all entities of that layer. When converted to ArcInfo, any combination of layers, and entities within each layer, can be specified for inclusion in a single ArcInfo coverage.

Vertex with bulge - describes a curve within a Polyline. (The bulge factor of a vertex is the tangent of one quarter the angle subtended at the center of an arc.). Each vertex with bulge is converted to a line feature with a vertex placed at 1 degree intervals to closely represent the original curve. All component features of a single polyline will share a common ID number.

DXF entity	Coverage feature	Comments
Line 3DLine	Arc	These entities become two-point arcs. The initial z value of 3-D entities is stored by ArcInfo.
Trace Solid 3DFace	Arc	These entities become four- or five-point arcs. The initial z value of 3-D entities is stored by ArcInfo.
Circle Arc	Arc	These entities form arcs. Circles are composed of 361 points - one vertex for each degree, with the first and last point at the same location.
Polyline	Arc	These entities can be grouped to form a single arc having many vertices.
Point Shape	Point	These entities become point features in a coverage.
Text	Point or Annotation	Text can be converted to an annotation feature or as a point location with the text as an attribute.
Attribute	Point or Annotation	Attribute can be converted to an annotation feature or as a point location with the text as an attribute.
Insert	Point	Inserts are converted to point features representing locations at which the block inserts are located.
Block	Point and/or Arc and/or Annotation	Blocks can be converted to several coverage features depending on the set of entities they contain.


Considerations when converting from ARC/INFO to DXF
Converting ArcInfo coverages to DXF

  Things to consider
  Standard items in the ACODE file
  Standard items in the XCODE file

Since AutoCAD does not accept a layer name that has an extension, the original ArcInfo coverage names should not include any suffixes. This is because the Coverage to DXF tool uses the input coverage names as part of each layer name it creates. Polygon coverages must have arc attributes to be converted. Use the Build tool with the Feature class set to Line before running Coverage to DXF. If label points exist for the polygon coverage, they can be converted as point features. For further information, consult the Coverage to DXF toolhelp.

ArcInfo feature	DXF entity	Comments
Arc	Polyline or Circle or Arc	The type of entity created by Coverage to DXF depends on the presence of certain items in the AAT.
Point	Point or Text	The type of entity created by Coverage to DXF depends on the presence of certain items in the PAT.
Annotation	Text	Each level of annotation is written as a unique DXF layer.
Polygon	-  -  -	To convert the arcs of a polygon coverage, first use the Build tool to create an AAT file and then convert as for arc features. If label points exist for the polygon coverage, they can be converted as point features.
Standard DXF items in the ACODE file

ACODE DXF-item Name	Valid DXF Options	DXF Group Code	Entities	Description
DXF-LAYER	LAYER NAME	8	LINE CIRCLE ARC SOLID TRACE POLYLINE 3DFACE	Layer name for the entity. Each entity belongs to a layer. Zero represents a special layer type in AutoCAD.
DXF-TYPE	DASH HIDDEN CENTER PHANTOMDOTDASHDOT BORDER DIVIDE OTHER	6	LINE CIRCLE ARC 2D POLYLINE	Linetype used to draw the entity. Can be set individually or by layer. If not set for individual entity, then the linetype set for the layer will be used.
	BLANK	NA	TRACE SOLID 3DFACE 3D  POLYLINE	Item value is blank for these entities. Linetype setting is ignored for these entities in AutoCAD.
DXF-COLOR	1 - 255	62	LINE CIRCLE ARC TRACE SOLID POLYLINE 3DFACE	Color used to draw the entity. Can be set individually or by layer. If not set for the individual entity, then the color set for the layer will be used. A negative color number means the layer the entity belongs to has been turned off.
DXF-ELEVATION	REAL NUMBER	38	LINE CIRCLE ARC TRACE SOLID POLYLINE 3DFACE	Elevation value for the entire entity. This DXF Group code contains a single elevation value. It is not used to assign multiple z values for a single entity and is only available for versions of AutoCAD prior to Release 11.
DXF-HANDLE	CHARACTER	5	POINT TEXT SHAPE ATTRIBUTE INSERT	This DXF code contains a hex value used by AutoCAD to uniquely identify DXF entities. This information may be used with additional information exported from AutoCAD as a link to attributes.
DXF-THICKNESS	REAL NUMBER	39	LINE CIRCLE ARC TRACE SOLID POLYLINE 3DFACE	Thickness for the entire entity. Can be used to store the elevation value for an entity in AutoCAD versions later than Release 10.
	1	NA	ARC CIRCLE	Used to flag entities defined as curves through a set of points whose vertices are calculated during the conversion using center and radius reference points.
DXF-CURVE	0	NA	LINE POLYLINE TRACE SOLID 3DFACE	Used to flag line features that will be converted back to a DXF file as POLYLINE entities.
Standard DXF items in the XCODE file

XCODE DXF-item Name	Valid DXF Options	DXF Group Code	Entities	Description
DXF-LAYER	LAYER NAME	8	POINT TEXT SHAPE INSERT ATTRIBUTE	Layer name for the entity. Each entity belongs to a layer. Zero specifies a special layer type in AutoCAD.
DXF-TYPE	STYLE NAME	7	TEXT   ATTRIBUTE	Style used to draw TEXT or ATTRIBUTE entities. Can be set individually or by layer. If not set for the individual entity, then the style set for the layer will be used. The default is STANDARD.
	BLANK	NA	POINT SHAPE INSERT	Item value will be BLANK for these entities.
DXF-COLOR	1 - 255	62	POINT TEXT SHAPE ATTRIBUTE INSERT	Color used to draw the entity. Can be set individually or by layer. If not set for the individual entity, then the color set for the layer will be used. A negative color number means the layer the entity belongs to has been turned off.
DXF-ELEVATION	REAL  NUMBER	38	POINT TEXT SHAPE ATTRIBUTE INSERT	Elevation value for an entity. This DXF code contains a single elevation value. It is not used to assign multiple z values for a single entity. It is only available for versions of AutoCAD prior to Release 11.
DXF-HANDLE	CHARACTER	5	POINT TEXT SHAPE ATTRIBUTE INSERT	This DXF code contains a hex value used by AutoCAD to uniquely identify DXF entities. This information may be used with additional information exported from AutoCAD as a link to attributes.
DXF-THICKNESS	REAL  NUMBER	39	POINT TEXT SHAPE ATTRIBUTE INSERT	Thickness for the entire entity. Can be used to store the elevation value for an entity in AutoCAD versions later than Release 10.
	REAL  NUMBER	40	TEXT ATTRIBUTE SHAPE	Height for TEXT and ATTRIBUTEs or size for SHAPE entities.
DXF-SIZE	REAL NUMBER	41	INSERT	Scale factor for the BLOCK referenced by the INSERT entity.
DXF-SIZE	0	NA	POINT	Item value is zero for POINT entities.
DXF-ANGLE	REAL  NUMBER	50	POINT TEXT SHAPE ATTRIBUTE INSERT	Angle of the X-axis for the *UCS in effect when the POINT was drawn or the angle of rotation for other entities.  *User Coordinate System
	ATTRIBUTE  NAME	2	ATTRIBUTE	ITEM name for the attribute value stored in DXF-TEXT for ATTRIBUTEs.
	BLOCK NAME	2	INSERT	BLOCK name referenced by INSERT.
DXF-ATTRIB	SHAPE FILENAME	7	SHAPE	Name of the file containing the commands that draw the SHAPE.
	BLANK	NA	POINT TEXT	Item value is blank for these entities.
DXF-TEXT	TEXT STRING	1	TEXT ATTRIBUTE	Text string for TEXT and attribute value for ATTRIBUTE entities.
	BLANK	NA	POINT SHAPE INSERT	Item value is blank for these entities.
DXF-IID	INSERT  SEQ NUMBER	NA	INSERT	ID number of the INSERT for the BLOCK name stored in DXF-ATTRIB.
DXF-IID	INSERT SEQ NUMBER	NA	ATTRIBUTE	ID number of the INSERT that the ATTRIBUTE is associated with.
	0	NA	POINT TEXT SHAPE	Item value is zero for these entities.


Converting IGDS data

Interactive Graphic Design Software (IGDS) files and MicroStation design files can be translated into ArcInfo coverages with the IGDS to Coverage Wizard. ArcInfo coverages can be translated into design files with the Coverage to IGDS Wizard. IGDS and MicroStation design files both have the same file structure and are both referred to as DGN files. Both are binary files organized into levels containing one or more drawing elements, or entities and both can be read by the IGDS to Coverage Wizard. Graphic attributes are stored in the design file. Database attributes are not. Instead each element can store pointers to attributes in external database files. These pointers, or linkages, are preserved during the conversion. The IGDS to Coverage Wizard can translate design files created on either PC, Vax, or UNIX platforms.

Before proceeding with the IGDS conversion, you should be familiar with each of the following elements of a design file and what features they can be translated into.


IGDS terminology

There are a total of 127 different element types possible in a design file. The IGDS to Coverage Wizard only translates the following eleven. All other elements that occur in a design file are ignored. An element is one of the entities that makes up a design file.

Cell - a complex element defining a group of elements that describe a symbol. Cells may either be placed as points positioned at the origin of the cell (its true location), or as the actual symbol described by its components. Each cell has a six-character name that is stored in the IGDS-TEXT item in the ACODE file. The cell element type number is 2.

Line - a two-vertex line. Lines are placed as two-vertex arcs. The line element type number is 3.

Line string - a multi-vertex line. Line strings are placed as multi-vertex arcs. The maximum number of vertices an IGDS line string can have is 101. The line string element type number is 4.

Shape - a closed multi-vertex polygon. Shapes are placed as multi-vertex arcs with identical starting and ending vertices. The shape element type number is 6.

Text node - a complex element defining a group of text elements having common characteristics, such as a paragraph where each line is a text element. Text nodes are ignored and their components placed as independent text elements sharing a common complex element ID in the IGDS-CPXID item in the ACODE file. The text node element type number is 7.

Curve - a parametric spline curve defined by a set of vertices and a cubic interpolation polynomial. Curves are treated like line strings and the interpolation between vertices is ignored. The curve element type number is 11.

Complex string - a complex element defining a group of connected linear elements (line, line string, curve, and arc). Complex strings are ignored and their components placed as independent elements sharing a common element ID in the IGDS-CPXID item of the ACODE file. The complex string element type number is 12.

Complex shape - a complex element defining a group of connected linear elements (line, line string, curve, and arc) that form a closed polygon. Complex shapes are ignored and the components placed as independent elements sharing a common element ID in the IGDS-CPXID item in the ACODE file. The complex shape element type number is 14.

Ellipse - an ellipse with an arbitrary primary and secondary axis of rotation. Ellipses are placed as 361 vertex arcs with identical starting and ending vertices. The ellipse element type number is 15.

Arc - an arbitrary section of an arbitrary ellipse. Arcs are stroked and placed as ArcInfo arcs. The number of vertices per degree of sweep varies with the amount of sweep to take care of arcs with extremely large radii. If the sweep angle is greater than 30 degrees, 1 vertex per degree is stroked. If the sweep angle is between 11 and 30 degrees, 5 vertices per degree are stroked. If the sweep angle is less than 11 degrees, 10 vertices per degree are stroked. The arc element type number is 16.

Text - up to 255 characters of text. Text may be placed either as points positioned at the text origin (its true location), or as annotation with the lower-left-hand corner at the text origin. Annotation rotation, spacing, and height are based on values in the text element. The first twelve characters of text are stored in the IGDS-TEXT item in the ACODE file. Enter data fields are ignored.  The text element type number is 17.

Other terms to be familiar with are:

Attribute linkage - value assigned to an element that points to a record in an attribute table that has attribute information about that element.

Level - data in a design file is segregated into 63 drawing levels. Levels are similar to transparent overlays that can be put together to form a complete drawing. Levels can be turned on and off independently in different views.

Color - one of the graphic attributes of an element. Valid colors are 0 to 255.

Line style - one of the graphic attributes of an element. Valid line styles are 0 to 7.

Line weight - one of the graphic attributes of an element. Valid line weights are 0 to 31.


Design file attributes

  Standard database linkages
  Other attribute linkages
  Linking database attributes to coverage features
  Example using dBASE files
  One-to-one relates
  One-to-many relates
  Joining attributes to feature attribute tables

Standard database linkages

MicroStation design files store graphic attributes for symbolization but do not store database attributes. Instead they store information that MicroStation uses to link elements to attribute data, information like; a database code, a table identifier, and a row number of a record containing a set of attributes. This attribute information, referred to in MicroStation as the database linkage, tells MicroStation where to find the attributes for elements in the design file. The database code represents one of the standard database packages supported by MicroStation. The numeric table-id numbers are indexed to table names in a file called the MSCATALOG which MicroStation uses to connect to external attribute tables. While the database linkages are contained in the design file and are preserved during the conversion, the actual table names and additional database information stored separately in the MSCATALOG file is only available in MicroStation. Your data provider may need to supply you with this information if you plan to access attributes stored in an external database once you have converted your design files. Attribute linkages can be stored for any element in the design file. The IGDS to Coverage Wizard stores attribute linkages for standard database packages in an INFO table named <Input coverage>.STDDB.

Up to 5 different attribute linkages can be stored for each element. Each linkage can reference different attribute tables, different databases and different linkage types.

Other attribute linkages

Most attribute linkages are database linkages which link elements to attributes in standard database packages. There are two other types of attribute linkages. USER data linkages and DMRS linkages. They are somewhat similar in structure but are used very differently.

USER definable linkages

USER data linkages are, for the most part, ignored by MicroStation because these linkages have special meaning to other MicroStation applications. There is no attempt to interpret this linkage type in ArcInfo because the information stored in them can vary from application to application and element to element. The IGDS to Coverage Wizard dumps these USER data linkages to an INFO table. Each linkage can have multiple records, each record can contain up to four words, each word contains the decimal equivalent of the hex value stored in the design file and will have very little meaning or use within ArcInfo. This information is useful only if you are converting from ArcInfo back to MicroStation. It is read by the Coverage to IGDS Wizard to re-construct the data linkages used by other applications in MicroStation. USER data linkages are stored in an INFO table named <Input coverage>.USER.

It is important to note that the INFO table storing this linkage type should not be edited. It should be treated as a read-only file. Editing records in this file can easily corrupt your design file if you are converting from ArcInfo back to MicroStation.

DMRS linkages

DMRS linkages are a carry over from design files coming out of the earlier, now obsolete, IGDS systems. To link converage features to attributes once stored in the IGDS DMRS database requires third party software that can convert the DMRS table format to some generic ASCII file format that can be read by other database packages.  Or you can use the DMRS linkages as a way to identify groups of features that have similar attributes that you can add attribute information to once you have done the conversion. DMRS linkages are stored in an INFO tabled named <Output coverage>.DMRS.

Linking database attributes to coverage features

The IGDS to Coverage Wizard stores attribute linkages to standard database packages in an INFO table called <Output coverage>.STDDB. This table contains the database linkages for all coverage features and is related to the feature attribute tables by the cover-ID which the wizard makes unique across the entire coverage. Each record contains all the database linkage information that is stored in the design file. Not all of this information is useful within ArcInfo but is very useful in re-constructing attribute linkages when you want to convert your coverage back to a design file.

List of items in OUT_COVER.STDDB:

   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC
 1  COVER-ID            4     5     B      -
 5  HEADER              4     4     C      -
 9  PRIMARY-ID          2     6     B      -
11  SECONDARY-ID        2     6     B      -
13  ENTITY              2     6     B      -
15  MSLINK              4    11     B      -

List of records in OUT_COVER.STDDB:

Record PARCEL-ID HEADER PRIMARY-ID SECONDARY-ID ENTITY MSLINK
    1     1      1007    29179       3969            1      6
    2     2      9007    29179       3969            2      2
    3     3      1007    29179       3969            3      8
    4     4      1007    29179       3969            1      3
    5     5      9007    29179       3969            1      1

HEADER - stores a value that represents properties for the database linkage. The code for the standard set of database linkage properties is 1007. Linkages that provide more information about another element will be coded as 9007. This code is not useful in ArcInfo but it is used by the Coverage to IGDS Wizard to re-construct original linkage information so it can be used in MicroStation. One of these two values is required in order for the Coverage to IGDS Wizard to correctly structure linkages in the design file. Normally the HEADER code will be 1007.

1007 - Standard linkage properties
9007 - Information linkage

PRIMARY-ID - stores the database code that identifies the database management system where the attributes are stored. The following are the PRIMARY-IDs of the database packages supported in MicroStation. ArcInfo DBI supports both Oracle and Informix. RIS is only supported by MicroStation. dBASE files are supported by both and can be used in ArcInfo by converting to INFO tables using the dBASE to INFO tool.

29179 	- dBASE
  6513 	- Oracle
24721 	- Informix
14664 	- RIS

SECONDARY-ID - is used internally by MicroStation.  It's use in MicroStation is unclear. It is not documented as having a significant roll in defining linkage properties but is stored in ArcInfo and is used by the Coverage to IGDS Wizard to re-construct the original database linkage. It is normally set to 3969.

ENTITY - stores the table identifier for the attribute table in the database identified by the PRIMARY-ID. The name of the table is not stored in the design file and this and other pertinent database information needs to be supplied by the data provider.

MSLINK - stores the row or record number in the table identified by the ENTITY number. This record will contain the attributes for the coverage feature. The cover.STDB may contain multiple records for the same coverage feature. This will occur when a feature has more than one set of attributes. Design file elements without attributes will not have database linkages and will not have a corresponding record the cover.STDDB.

Example using dBASE files

If the design file attributes are stored in dBASE files and you know the name of each file referenced by table identifiers, you can easily re-link the attributes to your newly converted ArcInfo coverage features using the attribute linkages stored in the <Output coverage>.STDDB file.

In this example we have a design file, PARCEL.dgn, and three dBASE files; PARCEL.dbf, LOT_HIST.dbf, and LOTS.dbf. Our design file contains parcel data where degenerate line elements, or points, represent polygon labels and linestrings represent closed polygon boundaries. Each element has at least one database linkage to one or more of the dBASE file. PARCEL.dbf has area attributes and both LOTS.dbf and LOT_HIST.dbf have line attributes. We have been given the ENTITY numbers that identify the dBASE files.

We convert PARCEL.dgn to a coverage containing line and point features and use the Build tool to create line and polygon topology. Our parcel coverage has 9 polygons that are made up of 30 line features. All 39 converage features have unique cover-IDs and each feature has at least one database linkage. We can tell from the number of records in PARCEL.STDDB, the file that stores database linkages, that there are multiple linkages.

Files created by the IGDS to Coverage Wizard:

TYPE NAME          INTERNAL NAME   NO. RECS LENGTH EXTERNL
-----------------------------------------------------------
DF  PARCEL.TIC      ARC0000DAT           4      20    XX
DF  PARCEL.ACODE    ARC0001DAT          39      78
DF  PARCEL.BND      ARC0002DAT           1      32    XX
DF  PARCEL.AAT      ARC0003DAT          30      68    XX
DF  PARCEL.PAT      ARC0004DAT          10      52    XX
DF  PARCEL.STDDB    ARC0008DAT          69      18

When we list the contents of PARCEL.STDDB file, we find that there is one attribute linkage for each polygon. The PRIMARY-ID = 29179 identifies the database type as dBASE. The ENTITY = 1 identifies a dBASE file containing the area attributes. For our example the dBASE file containing area attributes is PARCEL.dbf. This file name is not stored anywhere in the design file and should be supplied by the data provider. The MSLINK stores a pointer, or record number, to a record containing the attributes in PARCEL.dbf.

Values in PARCEL.STDDB:

Record  PARCEL-ID HEADER PRIMARY-ID SECONDARY-ID ENTITY  MSLINK
    1      1     1007    29179       3969            1       6
    2      2     1007    29179       3969            1       2
    3      3     1007    29179       3969            1       8
    4      4     1007    29179       3969            1       3
    5      5     1007    29179       3969            1       1
    6      6     1007    29179       3969            1       7
    7      7     1007    29179       3969            1       9
    8      8     1007    29179       3969            1       4
    9      9     1007    29179       3969            1       5

We use the dBASE to INFO tool to convert the PARCEL.dbf file to an INFO
table named PARCEL.

Values in PARCEL:

Record  PARCEL_NUM ASSESS_COD  ZONE_CODE
     1  960112     A-37        Housing
     2  954689     B-24        Commercial
     3  960023     F-15        Housing
     4  945678     O-11        Commercial
     5  960345     I-87        Industrial
     6  956721     H-23        Business
     7  954682     B-24        Commercial
     8  960343     F-15        Housing
     9  945478     O-10        Commercial

The PARCEL table contains area attributes we want to associate with the polygons in our PARCEL coverage. The STDDB records contain the information we need to do this. There is more than one approach we can take to do this.

One-to-one relates

You can relate the PARCEL table using stacked relates to list out attributes for selected features because there is a one-to-one relationship between area features and area attributes. To do this we define two ArcInfo relates: one to relate the PAT to the STDDB on PARCEL-ID, another to relate STDDB to PARCEL using item MSLINK and a Link type relate which will join the two tables by record number.

List of valid relates:

Relate Name:        STDDB
Table:              parcel.stddb
Database:           info
Item:               PARCEL-ID
Column:             parcel-id
Relate Type:        ORDERED
Relate Access:      RW

Relate Name:        PARCEL
Table:              parcel
Database:           info
Item:               MSLINK
Column:             $recno
Relate Type:        LINK
Relate Access:      RW

To list a single item in the PARCEL attribute table for set of area records requires the following syntax.

List of items parcel.pat parcel-id stddb//mslink stddb//parcel//zone_code:

Record  parcel-id stddb//mslink stddb//parcel//zone_code
     1      0     ***********   **********
     2      1               6   Business
     3      5               1   Housing
     4      6               7   Commercial
     5      2               2   Commercial
     6      7               9   Commercial
     7      3               8   Housing
     8      8               4   Commercial
     9      4               3   Housing
    10      9               5   Industrial

The syntax becomes cumbersome and the attribute listings become difficult to read when you list additional related items. Another difficulty is that you must know and specify the names of the items you want to list out.

List of items parcel.pat  parcel-id stddb//mslink stddb//parcel//parcel-num stddb//parcel//assess_code stddb//parcel//zone_code

              1
parcel-id                  =     0
stddb//mslink              = ***********
stddb//parcel//parcel-num  = ******
stddb//parcel//assess_code = ****
stddb//parcel//zone_code   = **********
              2
parcel-id                  =     1
stddb//mslink              =           6
stddb//parcel//parcel-num  = 956721
stddb//parcel//assess_code = H-23
stddb//parcel//zone_code   = Business

One-to-many relates

There are two dBASE files with attributes for line features. ENTITY = 2 corresponds to LOTS.dbf and ENTITY = 3 corresponds to LOT_HIST. We convert both dBASE files to INFO tables using the dBASE to INFO tool.

Values in LOTS table:

Record  CFCC DESCRIPTION
     1  e10  Fence
     2  e21  Ridge
     3  f40  Property
     4  h10  Stream
     5  b20  Railroad
     6  a10  Roads

Values in LOT_HIST table:

Record  SURVEY_DATE LOT_NUM
     1  960112      7602
     2  960112      7800
     3  950430      7900
     4  950324      8001
     5  960223      8002
     6  940527      8450
     7  940131      8401
     8  940214      8002
     9  960306      8402
    10  951012      8404

List of valid relates

Relate Name:        STDDB
Table:              parcel.stddb
Database:           info
Item:               PARCEL-ID
Column:             parcel-id
Relate Type:        ORDERED
Relate Access:      RW

Relate Name:        LOTS
Table:              lots
Database:           info
Item:               MSLINK
Column:             $recno
Relate Type:        LINK
Relate Access:      RW

Relate Name:        LOT_HIST
Table:              lot_hist
Database:           info
Item:               MSLINK
Column:             $recno
Relate Type:        LINK
Relate Access:      RW

The line features present more of a challenge because there are two database linkages for each line feature and relates do not support this one-to-many relationship. PARCEL-IDs for line features begin where polygon cover-IDs leave off at cover-ID = 10.

Values in PARCEL.STDDB table:

Record  PARCEL-ID HEADER PRIMARY-ID SECONDARY-ID ENTITY  MSLINK
    10     10     1007    29179       3969            2       9
    11     10     1007    29179       3969            3       1
    12     11     1007    29179       3969            2       2
    13     11     1007    29179       3969            3       2
    14     12     1007    29179       3969            2       1
    15     12     1007    29179       3969            3       1
    16     13     1007    29179       3969            2       5
    17     13     1007    29179       3969            3       3
    18     14     1007    29179       3969            2       2
    19     14     1007    29179       3969            3       2
    20     15     1007    29179       3969            2       6
    21     15     1007    29179       3969            3       5

Relating the AAT with the PARCEL.STDDB will only match to the first related record and will ignore the second related record. This is because relates only support one-to-one relationships. You will only be able to relate to the first set of related records. Processing one-to-many related records, requires the use KEYFILEs which is limited to ArcInfo’s ArcPlot module, or cursors which is more advanced and not normally used interactively. The alternative and simplest method is to resolve the one-to-many relationships by moving the attributes onto the feature attribute tables. This is a multi-step process and cannot be done by directly joining the attributes onto the FATs. Refer to the next section, "Joining attributes to feature attribute tables" for a detailed description of how to do this.

Joining attributes to feature attribute tables

Moving attributes directly onto the feature attribute tables will greatly simplify attribute listings and spatial selections with attribute based queries. Accomplishing this involves a series of steps because there is no direct link from the FATs to our attribute tables.

Step 1: Create a temporary JOIN table

First we create a temporary table that has database linkage records for only one ENTITY. We use the Copy Items tool to create the JOIN table with the PARCEL-ID, MSLINK, and ENTITY items, then we delete records that are not associated with the attribute table we want to join to our FAT. In this example we are joining area attributes in PARCEL to PARCEL.PAT. Our temporary JOIN file will only contain records with ENTITY value of 1.

Use the ArcCatalog’s table editor to select all records that do not have an entity value of 1 and delete them.

Step 2: Join attributes to the JOIN table

Join PARCEL attribute table to the JOIN table. We use the Link option in the Join Tables tool because MSLINK contains the record number rather than a relate key value.

Step 3 Join temporary JOIN table to the coverage via the cover-ID.

Use the Join Tables tool to join the PAT and the JOIN table.

Listing of PARCEL.PAT values:

Record  PARCEL# PARCEL-ID  PARCEL_NUM ASSESS_COD  ZONE_CODE
     1      1       0               0
     2      2       1          956721 H-23        Business
     3      3       5          960112 A-37        Housing
     4      4       6          954682 B-24        Commercial
     5      5       2          954689 B-24        Commercial
     6      6       7          945478 O-10        Commercial
     7      7       3          960343 F-15        Housing
     8      8       8          945678 O-11        Commercial
     9      9       4          960023 F-15        Housing
    10     10       9          960345 I-87        Industrial

For the line features that are the lot boundaries in our PARCEL coverage, there are two related attribute tables identified by different ENTITY numbers. The same method used to join the PARCEL attributes onto the PAT is used is used for the AAT.; but each step is performed twice, once for  each attribute table, LOTS and LOT_HIST. ENTITY. The end result with be both sets of attribute tables joined to the ATT. This will resolve the one-to-many relationship we have for line features in our PARCELs coverage making attribute selection and query operations very straightforward.

Listing of PARCEL.AAT table:

Record  PARCEL# PARCEL-ID CFCC DESCRIPTION  SURVEY_DATE LOT_NUM
     1      1      13     f40  Property     960223      8002
     2      2      14     e21  Ridge        960112      7800
     3      3      15     b20  Railroad     940527      8450
     4      4      16     e10  Fence        960112      7602
     5      5      17     f40  Property     960223      8002
     6      6      18     e21  Ridge        960112      7800
     7      7      10     e10  Fence        960306      8402
     8      8      19     e21  Ridge        960112      7800
     9      9      20     h10  Stream       950324      8001
    10     10      21     f40  Property     950430      7900
    11     11      22     a10  Road         940214      8002
    12     12      11     e21  Ridge        960112      7800
    13     13      23     f40  Property     950430      7900
    14     14      24     f40  Property     951012      8404
    15     15      25     e21  Ridge        960112      7800


ARC/INFO to IGDS
ArcInfo to IGDS

ArcInfo coverages may be converted into IGDS files. The Coverage to IGDS Wizard gives a great deal of flexibility on how you may translate your coverage. Two of the translation methods require the existence of an <Input coverage>.ACODE table. The ACODE table is created with the IGDS to Coverage Wizard. If you use one of these methods and create your own ACODE table, be sure that it is the exact same format as the one created by the IGDS to Coverage Wizard. Coverages without an ACODE file are usually created by some means other than the IGDS to Coverage Wizard. Graphic attribute values for elements created using the ACODE file may be assigned using a property map. A property map is just an INFO table that you create with graphic attribute values for elements. The Coverage to IGDS Wizard uses the property map file to assign graphic attribute values to elements. If you do not use this option when you do not have an ACODE file, all output elements will have the same graphic element values (e.g., all elements will be on level 1, etc.). You may also use cells in your translation.

The Coverage to IGDS Wizard allows you to control what ArcInfo features are translated, and you have some control over what elements those features are translated into. The following chart summarizes what ArcInfo features may be translated into what elements.

Input features	Valid output elements
ANNO	TEXT, TEXTNODE
TIC	LINE, TEXT, TEXTNODE, CELL
POINT	LINE, TEXT, TEXTNODE, CELL
POLY 2-ARC	COMPLEXSTRING, COMPLEXCURVE, LINESTRING, CURVE
N-ARC	LINE, LINESTRING
CURVE	LINESTRING, CURVE, COMPLEXSTRING, COMPLEXCURVE
	ARC, LINESTRING, CURVE, COMPLEXSTRING, COMPLEXCURVE
The Coverage to IGDS Wizard requires a seed design file from which certain header elements are copied to your output design file. If you do not have a seed design file to use, you may try one of the sample design files located in $ARCHOME\template\igds.

Adding new linkages to IGDS coverages

The Coverage to IGDS Wizard will re-construct or create attribute linkages using the three linkage tables; USER, DMRS, and STDDB, discussed in the section Design file attributes. If you originally converted your coverage from a design file and saved the associated attributes, and there exists a cover.alink system file, this file will be used instead of the INFO files. Delete this file if you want your attribute linkages to be read from the linkage tables in INFO.

Make sure that new features you want to attribute with additional database information, have records in both the ACODE and STDDB files and be sure you assign the appropriate values to IGDS-PROPS in the ACODE file, and to HEADER, PRIMARY-ID and SECONDARY-ID in the STDDB file. An invalid STDDB value may corrupt your design file. Refer to Linking database attributes to coverage features for guidelines on the correct values to use.

To convert attributes for newly created coverages

Creating dBASE linkages is a simple approach because you can create dBASE files in ArcInfo using the INFO to dBASE tool and you can view attributes in the dBASE files in MicroStation provided your dBASE files are indexed in the MSCATALOG in MicroStation. If the attributes you want access to in MicroStation are in your feature attribute tables, here are the general steps to prepare your coverage before converting.

Step 1: Add records for new features in both ACODE and STDDB files

Step 2: Set bit 5 in IGDS-PROPS (i.e.; 00001000 where 1 indicates attributes present)

Step 3. Convert feature attribute tables to dBASE files using the INFO to dBASE.

Step 4. Define STDDB table

You can use the Copy Items tool to create a file containing <cover>-ID and add STDDB items to it.

Step 5: Assign values to ENTITY and MSLINK items in STDDB

Relate the feature attribute table to STDDB on <cover>-ID. Assign a numeric ID number for ENTITY to identify the dBASE files. Calculate the MSLINK equal to the <cover>#. Each feature attribute table will have a unique ENTITY number, MSLINK will have a unique set of record numbers for each ENTITY ID.

You can create new database linkages that you can use in MicroStation if you have access to the same database in both ArcInfo and MicroStation. For example, if your coverage attribute information is stored in an Oracle database and you have access to the same Oracle database in MicroStation. You can create a design file with Oracle database linkages from your ArcInfo coverage using the Coverage to IGDS Wizard and view the design file with the same attribute information in MicroStation provided your MSCATALOG is configured with the correct table identifiers and database info to connect to your Oracle database.

If you are creating linkages to attributes to databases only accessible in MicroStation, you will need to consult a DBMS guide to determine the appropriate export format needed to move attributes from one database package to another.


Factors to consider when translating files

If you translate a design file into a coverage and plan to translate the coverage back into a design file you should translate cells with the to a point when you run the IGDS to Coverage Wizard. Cell information is only translated back into a new design file if the input feature is point.

When you add features to a coverage that was created with the IGDS to Coverage Wizard and you plan to translate the edited coverage back into a design file using either the ACODE file or the Source method, be sure you add corresponding records to the ACODE file.

If you translate a particular data set from IGDS to ArcInfo to IGDS, and so on, and if you use the SOURCE option, be sure the source design file you use is the latest design file in the sequence. In other words, do not use the very first design file you translated as the seed_dgn for the nth iteration of the Coverage to IGDS translation.

In some cases, a design file will need to be copied from one operating system to another (e.g., VAX to UNIX) using FTP. If this is necessary for you, be sure to use the binary option with the FTP copy; otherwise, your IGDS file will not translate properly.


Converting DLG  data

Digital line graphs (DLG) are geographic data files provided by the Earth Science Information Center (ESIC, formerly NCIC) of the U.S. Geological Survey. These data files include information from the USGS planimetric map base categories such as transportation, hydrography, contours, and public land survey boundaries. The DLG format is also often used to transport data between ArcInfo and other mapping systems.

There are two DLG formats: DLG standard and DLG optional format. These are documented in the DLG Data Users Guides available from any of the USGS Earth Science Information Centers. You should acquire all DLG documents if you plan to use DLG data or DLG formats to transfer ArcInfo data.

DLG files are available for the following USGS map series:

7.5- and 15-minute topographic quadrangle series

1:100,000-scale quadrangle series

1:2,000,000-scale national atlas maps


The DLG data structure

The DLG data structure is a full topological data structure which contains three elements (or features): nodes, lines, and areas. DLG nodes define the locations of endpoints for every DLG line. A DLG line is an ordered set of points which define the position and shape of a linear feature or part of an area boundary. A single node may mark the start or end of one or more lines. This structure is similar to arcs and nodes in an ArcInfo coverage.

A DLG area is a portion of the map sheet bounded by a set of lines. Each area contains an arbitrary centroid point used to assign a sequence number to the area. A DLG area is equivalent to a coverage polygon in ArcInfo; that is, it is composed of a set of lines which define its boundary.

In addition to storing locational and topological data, DLGs also have numerical attributes which describe each feature. Attribute codes are organized as major and minor pairs. Code pairs are encoded in two integer fields each containing six digits (i.e., FORTRAN 2I6 format). Each major code represents the category or class to which a DLG feature belongs (e.g., road, stream, or other line class), while minor codes describe each feature more specifically. Thus, a feature class can have multiple pairs of attribute codes.

Up to twenty major/minor code pairs can be contained in a DLG. (The most we have encountered at ESRI is twelve pairs.) These code fields are equivalent to INFO items defined as 6,6,I. The interpretation of each code value is dependent upon the DLG layer and map series. Typically, a document describing the coding system is included with each DLG file so you can interpret the code descriptions for each DLG feature.

The DLG standard format contains 144 bytes per record, and the optional format contains 80 bytes per record. ArcInfo can read either format using the DLG to Coverage Wizard. Only the newer optional format can be created from ArcInfo coverages using the Coverage to DLG tool.


DLG optional format

The DLG optional format is the most accepted method for transferring map data because it stores topology with area or node records (while the DLG standard format stores topological information with line records), and because it has a shorter record format (80 compared to 144 bytes per record). This ability to record coordinates, feature topology, and descriptive attributes has made the DLG format a popular, public-domain format for data transfer.

Each DLG has three record types, one for each feature class: N (node) records, A (area) records, and L (line) records. There is one record for each DLG feature. Each record contains a feature number, coordinate values, attribute code pairs for the feature (if they exist), and topology if the file is in the DLG optional format. (The DLG standard format records feature topology with line records only.)

Comparison of DLG and ArcInfo coverage features

DLG Features	ArcInfo equivalents	Comments
Nodes (N records)	Nodes	Both DLG nodes and coverage nodes represent endpoints of arcs that can be assigned attributes.
Lines (L records)	Arcs	Both DLG lines and coverage arcs represent linear features and/or polygon boundaries.
Degenerate lines (L records)	Label points	DLG code pairs become point attributes in the output coverage from the DLG to Coverage Wizard. Coverage point features are automatically converted into degenerate line records in the output DLG for Coverage to DLG.
Areas  (A records)	Polygons	Both DLG areas and coverage polygons contain label points which are used to assign feature numbers.
Control points (in DLG header)	Tics	Four control points record the x,y locations of the four corners of a DLG. A coverage can contain more than four tics, which can occur anywhere within a coverage. Control points are converted to tics by the DLG to Coverage Wizard. When using Coverage to DLG, the control points are read from the {in_header_file}.
Topology (in N, L and A records)	Topology	ArcInfo and DLG store topology similarly, though not identically. DLG to Coverage Wizard ignores all DLG topology. Once a coverage is created from a DLG file, topology is created using the Build or Clean tools.
Major/minor code pairs (in N, L or A records)	Items in feature attribute tables	DLG supports multiple code pairs defined as FORTRAN 2I6 format. ArcInfo items do not have to be paired and can be integer as well as binary integer (B), binary real (F), numeric (N), character (C), and date (D).  ArcInfo can use relational tables to store as much descriptive data as desired.
DLG Features	ArcInfo equivalents	Comments
Map projection (usually UTM)	Any projection	DLG headers contain a code description of the map projection which is almost always UTM. The coverage stores this projection information but, unlike DLG, the projection for a coverage can be changed.


Comparison of DLGs and ARC/INFO coverages
Comparison of DLGs and ArcInfo coverages

There are a number of similarities between DLG features and ArcInfo coverages. However, there are also some notable differences.

All map data is stored in a single DLG file, whereas an ArcInfo coverage is stored as a set of related files in a directory.

DLG files can contain more than one category. In some circumstances, more than one coverage can be created from a single DLG file.

Point features, which are represented by label points in an ArcInfo coverage, are represented as degenerate lines in a DLG file. A degenerate line is a line which has zero length; it has two identical vertices (i.e., both have the same location).

DLG files contain header information describing the map name and category, the data source, the input resolution and scale, map projection information, and a set of four control points, one for each corner of the DLG area. These control points are similar to coverage tics. Source and history information can be added to the coverage log file that records each operation performed on the coverage. This information remains with the coverage until deleted.

The DLG header also contains information about how coordinates were transformed (i.e., scaled and offset) when they were written to the DLG. The coordinate fields are too small to store high coordinate precision. All DLG coordinates are in single precision while coverage precision can be either single or double.


Creating coverages from a DLG file

The data contained in a DLG data set delivered by USGS may contain up to four feature classes - areas (polygons), lines, degenerate lines (points), and nodes - each of which may have attribute codes. To maintain these data in an organized manner, the DLG to Coverage Wizard has options to create two output coverages. It will be important to be aware of the data categories contained in each DLG file to be converted.

The DLG to Coverage Wizard is used to convert a DLG file, in either standard or optional format, into ArcInfo coverages. The following steps outline the process used to convert a DLG file. The process presented here is simplified. In your application, you may have additional issues which must be addressed. A discussion of these additional considerations is presented at the end of this section.

To best understand the steps that follow, refer to the DLGARC command reference in the ARC Command References.

  Step1: Output options
  Step2: Run the DLG to Coverage Wizard
  Step3: Create topology
  Step4: Major/Minor codes
  Step5: Joining attribute tables

Step 1:  Identify the contents in the DLG file

The purpose of this step is to identify the set of output coverages to be created by the DLG to Coverage Wizard. Identify the feature classes contained in the DLG file and the sets of attribute codes available for those features.

You can create an output line coverage for DLG arc, area and node features and a point coverage for the DLG degenerate lines.

Step 2:  Convert the DLG file into a set of coverages using  the DLG to Coverage Wizard.

Topology

For a standard DLG file from USGS, the Output coverage will usually contain both line and polygon features. However, since ArcInfo and DLG topology are represented differently, the DLG to Coverage Wizard does not convert the DLG topology. The Build and Clean tools must be used to recreate coverage topology. The INFO tables created for the output coverage include a node attribute table (NAT), a PCODE table which contains polygon attribute codes for each DLG area (A) record, and an ACODE table which contains arc attribute codes for each line (L) record.

A point coverage and INFO table XCODE table will be created if you specify the Point coverage option. If you do not know whether the DLG contains degenerate lines, you can specify that the additional coverage be created.

Empty point coverage

Specifying this optional output point coverage when no corresponding point features exist in the DLG file will result in the creation of an empty coverage. If empty coverages are created, you should delete them.

Step 3:  Create coverage topology and feature attribute tables for the new coverage or coverages

The DLG to Coverage Wizard gives you the choice to build the feature attribute tables for the converted feature classes and then join them to the associated attribute tables.

Once the feature attribute tables for each coverage are built, the User-ID (i.e., Cover-ID) in the feature attribute table can be related to the <cover>-ID item in the CODE files to associate major and minor code pairs with the coverage features.

Step 4:  Record better interpretations of major and minor attribute codes (optional)

Since all DLG attributes are recorded in major and minor code pairs and are integer codes, you may want to provide a more meaningful description for each attribute code. You may also wish to delete or remove redundant codes (found where all coverage features have the same code value representing the feature class).

In cleaning up DLG attributes, you may want to develop your own items by putting all major codes into one item and all minor codes into separate items each having a more descriptive name.

For example, consider this partial list of minor code values and their descriptions for a 1:2,000,000-scale DLG file of rivers and streams.

Minor code	DLG Description
: 3001 3002 3002 3003 3004 3005	: Shoreline Stream centerline Perennial stream, length < 20 km (12 mi) Perennial stream, length 20-<30 km (12-< 19 mi) Perennial stream, length 30-<40 km (19-< 25 mi) Perennial stream, length 40-<50 km (25-< 31 mi) :
These data can be recorded in an INFO table as two items: the minor code as an integer item, and the description as a character item. Here, a symbol item is also recorded for each coded value.

STREAM-CODE   TEXT	     SYMBOL
3001	Shoreline	23
3002	Stream centerline	16
3002	Perennial stream, length <20 km	7
3003	Perennial stream, length 20-<30 km 	7
3004	Perennial stream, length 30-<40 km 	10
3005	Perennial stream, length 40-<50 km	10

Step 5:  Join major and minor codes from the INFO tables (i.e., PCODE, ACODE or XCODE) into the coverage feature attribute table (optional)

If desired, you can use the join option in the DLG to Coverage Wizard to join attribute codes into the coverage’s feature attribute table.


Additional considerations for DLG conversion

  DLG datasets
  Common coordinate system (map projection and tics)

DLG datasets

The conversion process described in the last section can be used for any individual DLG file. However, users typically plan to convert a number of DLG layers for more than one adjacent area. In these cases, there are additional issues regarding the assembly and integration of a map database which spans a large area. Here are some important issues to address.

DLG files replicate the appearance of the paper maps and may not result in the desired level of connectivity. For example, a highway underpass will break the connectivity of a road network.

No consistent method is used to record DLG major codes. Often, major codes are blank for some features. For example, road class does not always precede road number in DLG line (L) records representing roads.

DLG files contain neatlines representing the map sheet boundary. These are usually represented by the first area (A) record in the DLG, and the label point for this area record is usually located in the center of the resulting coverage. If other DLG areas are present, then the polygon in the center of the resulting DLG coverage will contain two label points: one for the neatline polygon and one for the actual polygon.

The 1:2,000,000-scale national map atlas DLGs for state/county boundaries and streams contain double-digitized polygons (i.e., polygon loops instead of arc-node data structures for areas). These must be cleaned with the CLEAN command.

DLG files represent the contents of USGS map sheets which are often out of date. If your application requires up-to-date map data, you will have to compare the DLG data to other base maps and photos.

Common coordinate system (map projection and tics)

Prior to creating each DLG coverage, you most likely will establish the map projection and coordinate system to be used to record x,y locations and coordinates for your geographic database. The coordinate system (i.e., map projection) used may not be the same as the UTM projection in which DLG data is delivered. Thus, it is most appropriate to use one set of tics with standard Tic-IDs for all coverages in your study area. Two properties of the DLG command need mentioning:

Tics are generated by the DLG to Coverage Wizard at the four corners of the DLG extent. They receive Tic-IDs 1, 2, 3 and 4. In a large database, these tics must be replaced so that the Tic-IDs in the DLG coverage will match the existing tics in other coverages and layers in the database.

The map projection of the DLG coordinates may be different than your geographic database. If your map database is in a different map projection, you will need to change the map projection of each DLG coverage using the PROJECT command.

The map projection is stored with each coverage created by the DLG to Coverage Wizard. The projection (PRJ) file defines the UTM projection of the DLG file. The coverage projection file (PRJ) records the UTM zone or a lat-long value for a point from which the zone can be determined. (Please note that in the PARAMETERS section, the lat-long values will not be written to the coverage projection if the DLG header includes the zone number.) Usually, the first step is to project each DLG coverage into the same map projection as your geographic database. Then you can copy the master tic file into each DLG coverage to replace the original DLG corner tics.

Please note that when projecting, transforming, and copying your DLG to coverage conversion results, your ACODE and PCODE tables in INFO will also be copied each time. Therefore, you may want to delete extra copies to reduce the required disk space for DLG processing.


Creating a DLG file from a coverage

The Coverage to DLG tool is used to create a DLG file in optional format from one or more ArcInfo coverages.

Please refer to the tool’s help reference for a description of its use. The following steps describe how the tool can be used to generate a DLG file. It is worth noting that although the DLG file produced by ArcInfo complies with the USGS format, it will differ slightly from one created by the USGS. For example, you should expect the feature numbers used to record topology to have different values.

Step 1:  Define the contents to be included in the output DLG

The set of input coverages to be specified will depend upon the set of features to be contained in the resulting DLG file. Include an identification of the desired feature classes and their attribute codes (e.g., how many major/minor code pairs and what code values). The following table will help identify the set of input features to be included in the DLG.

MAJOR1	MINOR1
MAJOR2	MINOR2
  :	 :
MAJORn	MINORn

The Coverage to DLG tool first looks for these items in the standard attribute tables created by the DLG to Coverage Wizard. If these files do not exist, then the appropriate feature attribute tables will be searched.

Input Coverage	Standard Attribute Table	Feature Attribute Table	Feature class	DLG record
Input coverage	ACODE	AAT	ARCS	Line (L)
Input coverage	PCODE	PAT	POLYS	Area (A)
Input coverage	(none)	NAT	NODES	Node (N)
Point coverage	XCODE	PAT	POINTS	Line (L)
Step 2:  Prepare the set of input coverages

In this step, you should ensure that you have correctly created coverage features for the DLG file. Topology should be generated for polygon and arc features. During DLG creation, each feature’s internal number (i.e., Cover# in the feature attribute table - not the Cover-ID) is used as the feature number recorded in the output DLG. This ensures that each DLG feature number is unique and sequential.

If a coverage has been recently updated, you should renumber the feature internal numbers which are used in the topology lists by running RENODE on the input coverage. This will ensure that all arc, node, and polygon feature internal numbers are sequential.

If degenerate line (L) records (i.e., point features) are to be included in the output DLG, you should prepare a point coverage. If you want to include node attributes for (N) records for node features in the Input coverage use the Build tool with the Feature class set to Node to build the table and add the appropriate major / minor code pairs.

The final step in preparing your coverages is to project each input coverage into the appropriate map projection (usually UTM) for the output DLG. Use the Project Wizard to perform the projection change.

Step 3:  Prepare the major/minor code pairs in the feature attribute tables of each input coverage

Item names for major and minor code pairs are shown in Step 1. Major and minor code pairs are automatically written to the output DLG by the Coverage to DLG tool if they are found in the input coverage feature attribute table or CODE files. They must be named MAJORn and MINORn (where n is the number of the code pair) and must be defined as an integer item (i.e., B or I) less than or equal to six digits wide. There should be pairs of items to represent each code pair. The Coverage to DLG tool will recognize as many attribute pairs as is desired.

DLG attributes are always integer pairs containing one to six digits. Items must be paired and defined as numeric items. Real numbers are truncated when written to the DLG. Please be aware of the item value used to represent ‘No data’ or a blank code value in the DLG: -99999. An item value of 0 will be written as 0 to the DLG. The -99999 convention is recognized by Coverage to DLG as ‘No data’ and recorded as a blank in the DLG.

Step 4:  Projection file (PRJ)

The Coverage to DLG tool reads the coverage projection from the projection definition (PRJ) file. It is not necessary to provide a text file containing the map projection parameters for the input coverages if the projection has already been defined. If the Projection file option is used, the file should be in the same format as used by the Project Wizard. In both cases, the projection is read by the Coverage to DLG tool and translated into projection information recorded in the header records of each DLG.

If coverage projection has not been defined and a Projection file is not used, then no projection information will be written to the output DLG file.

Please note that Coverage to DLG tool does not use this file to change the map projection of each input coverage. You must change the projection using the Project Wizard.

Step 5:  Build the header information file

The header information file is a text file containing key information to be contained in the output DLG header records. Refer to the Coverage to DLG help for the format and contents to be included in this file.

Step 6:  Create the DLG file using the Coverage to DLG tool.

Now that you have created each of the input coverages and feature attributes, the projection file and the header information file, you are ready to create an output DLG using the Coverage to DLG tool. Please note that this will create an optional format DLG file. Each record is fixed length at 80 bytes.


Using DLG to transfer data

Since the DLG format is public domain and a number of data sets are available, the DLG format can also be a useful format for data exchange between ArcInfo and other mapping systems. A number of mapping systems support a DLG interface. The following considerations will be important when transferring coverages using the DLG format.

It is not necessary to use a complete DLG format when importing data into ArcInfo. For example, you can keep attribute data in a separate file instead of using DLG major and minor codes which can be cumbersome and limiting.

A separate file of feature attributes must contain fixed-length records in an ASCII text format. Each record should contain the same fields (i.e., items) and in the same position. For example, columns 1 to 4 contain the feature number, columns 5 to 15 contain the name, columns 16 to 20 the feature class, and so on.

Creating such a text file in INFO is relatively easy. Here is an example which shows how a text file of attributes was created for an ArcInfo coverage named STREETCOV.

Arc: INFO
ENTER USER NAME> ARC
ENTER COMMAND > SELECT STREETCOV.AAT
   2293 RECORD(S) SELECTED

ENTER COMMAND > ITEMS
 DATAFILE NAME: STREETCOV.AAT
   19 ITEMS: STARTING IN POSITION    1
 COL  ITEM NAME         WDTH OPUT TYP N.DEC
    1  FNODE#              4    5  B    -
    5  TNODE#              4    5  B    -
    9  LPOLY#              4    5  B    -
   13  RPOLY#              4    5  B    -
   17  LENGTH              4   12  F    3
   21  STREETCOV#          4    5  B    -
   25  STREETCOV-ID        4    5  B    -
   29  CLASS               2    2  I    -
   31  STREET.NAME        21   21  C    -
   52  STREET.TYPE         5    5  C    -
   57  SUF-DIR             2    2  C    -

First, specify the pathname of an output text file which will contain the attribute data.

ENTER COMMAND > OUTPUT PATH>DLGOUT.ATT

Next use the DISPLAY command with the PRINT option to write item values into the attribute text file. Be sure to include the <cover># item so that each attribute record can be related to its DLG feature.

ENTER COMMAND > DISPLAY STREETCOV#,1X,CLASS,1X,STREET.NAME,1X,STREET.TYPE PRINT

ENTER COMMAND > QUIT

Below is a partial listing of the text file created in INFO. The first number lists the feature number which is also recorded in the DLG. Notice that this list includes both numeric and character attributes. (Remember that a DLG can only record integer values for attribute codes.)

     1  2 SAN BERNARDINO        AV
     2  2 SAN BERNARDINO        AV
     3  2 SAN BERNARDINO        AV
     4  2 SAN BERNARDINO        AV
     5  2 SAN BERNARDINO        AV
     6  2 SAN BERNARDINO        AV
     7  2 SAN BERNARDINO        AV
     8  2 SAN BERNARDINO        AV
     9  2 SAN BERNARDINO        AV
    10  2 SAN BERNARDINO        AV
    11  2 SAN BERNARDINO        AV
    12  2 SAN BERNARDINO        AV
    13  2 SAN BERNARDINO        AV
    14  2 SAN BERNARDINO        AV
    15  2 SAN BERNARDINO        AV
    16  2 SAN BERNARDINO        AV
    17  2 SAN BERNARDINO        AV
    18  3 KIMBERLY              AV
    19  3 ROBYN                 ST
    20  3 GAIL                  AV
    21  3 ROBYN                 ST

One of the fields (usually the first) should contain a feature number which can be used to relate each attribute record to a single feature in the DLG file. When creating a DLG file with the Coverage to DLG tool, this should be the feature internal number (i.e., the <cover># item from the feature attribute table). This will provide a relationship between records in the DLG and the attribute file, since the output DLG created by Coverage to DLG lists the <cover># number as the DLG feature number.

A document describing the contents of the output DLG should be written which also identifies the name and position of each attribute field, its item type, range of values, and other interpretive information as needed. This document should also describe how to read the data files from magnetic tape or other transfer media.


Converting Vector Product Format data

Vector Product Format (VPF) is a U.S. Department of Defense Standard. The National Imagery and Mapping Agency (NIMA) is using VPF for digital vector products developed at a variety of scales. VPF has also been adopted into an international spatial standard as the Digital Geographic Information Exchange Standard (DIGEST).

VPF is a standard format, structure, and organization for large geographic databases that are based on a georelational data model.

The VPF data model has five levels. At the lowest level, a VPF database consists of geometric and cartographic primitives. A primitive is the smallest component of the VPF data structure (primitives that are related to thematic information are called features). Both features and primitives make up coverages, which in turn make up libraries; and finally, a database is made up of libraries. Primitives are the VPF equivalent of ArcInfo coverage files (e.g., arc, pal, lab).

Vector Product Format (VPF) coverages and tables can be translated into ArcInfo coverages and INFO tables with the VPF to Coverage tool. ArcInfo coverages and INFO tables can be translated into VPF coverages and tables with the Coverage to VPF tool.

VPF product specifications

When VPF products are made, they are usually made in accordance with a product specification. Although anyone can write a product specification, most of the product specifications available are authored by NIMA. Several of these product specifications are available online at http://www.nima.mil/publications/pub.html.

All product specifications must follow the rules specified in the VPF Product Standard:
MIL-STD-2407	Vector Product Standard (also available from NIMA)

Some example product specifications include:
MIL-PRF-89036	Urban VMap (UVMap)
MIL-V-89033	Vector Smart Map Level 1 (VMAP1)
MIL-V-89039	Vector Smart Map Level 0 (VMAP0)
MIL-PRF-89032	Vector Smart Map Level 0 (VMAP 2)
MIL-PRF-89023	Digital Nautical Chart (DNC)

When VPF data is made, it needs to conform to the product specification. In order to do this we must have the ability to customize the VPF tables on output. We do this through the use of conversion control files (CCFs). All the information needed to create a CCF can be found in the specification for the data product.


VPF terminology

The following discussion includes mention of ArcInfo equivalents, where appropriate (e.g., edges becomes arcs).

Coverage: A set of primitive tables plus all of the feature classes built from that set of primitives.

Feature: A model of a real-world geographic entity including both its location and its properties. A feature is a combination of one or more primitives and a row of attributes from one or more feature tables.

Primitive: Describes the geometry and topology of a feature. There are four geometric primitives in VPF: edges, faces, nodes, and text.

Edge: A two-dimensional primitive used to represent the locations of linear features and the borders of faces. Edges become arcs.

Face: A two-dimensional primitive enclosed by edges; faces are used to represent area. Faces become polygons.

Node: A zero-dimensional primitive used to store significant locations. There are two type of nodes: entity nodes and connected nodes. Entity nodes become points and connected nodes remain nodes.

Text: A cartographic primitive not topologically linked to any of the geometric primitives. Text becomes annotation.

Primitive table: Contains coordinate and ID information for the related feature table.

Feature table: A table made up of rows of features in a feature class (point, line, area, text, complex). These rows collectively form the feature table for that feature class. The columns of a feature table represent the feature class attributes. Normally contains a link column to the primitive table.

Feature index table: A table constructed specifically to provide for rapid retrieval of feature information when given a selected primitive. It provides a join index from primitive to feature.

Feature join table: A table that maps 1:N or N:1 relationships between features and other features or primitives. Simple features may be composed of one or more primitive instances, and complex features may be composed of one or more simple features or other complex features. A primitive instance may belong to more than one feature.

Level: Indicates topological complexity. The Coverage to VPF tool will create the topology of four levels. A polygon coverage will be level 3. A polygon coverage where polygons are ignored will be level 2. Line coverages are level one and point coverages level 0.

Library attribute table (lat): Acts as the database table of contents. The library attribute table contains the ID, Library_Name, and graphic extent (xmin, ymin, xmax, ymax) of all the libraries contained in the database.

Database header table (dht): Contains database transmittal information.

Library header table (lht): Stores general information about a library.

Geographic reference table (grt): Defines the coordinate system of a library.

Coverage attribute table (cat): Contains the ID, coverage name, description and topology level of all the coverages in the library.

Value description table (vdt): Describes coded attributes in VPF feature tables.

Lineage.doc: Contains information from the ArcInfo log file.


Converting VPF data into ArcInfo format

When importing a VPF coverage, a number of tables are created based on the level of topology that the VPF coverage contains. The VPF level of topology defines the maximum level of topology for that coverage. For example, a coverage with VPF topology level 2 contains entity nodes and may also contain entity and connected nodes as well as edges. The following tables show what ArcInfo feature tables will be created from the VPF feature, join, and primitive tables.

One-to-one feature table mappings
Default names of VPF feature tables	Coverage feature attribute tables
epoint.pft (entity node feature table)	PAT (point attribute table)
cpoint.pft (connected node feature table)	NAT (node attribute table)
line.lft (line feature table)	AAT (arc attribute table)
area.aft	PAT (polygon attribute table)
<subclass>.tft (text feature table)	SubclassTAT (text subclass attributes table)
Many-to-many feature table mappings
Default names of VPF feature and join table	Coverage feature attribute tables
<subclass>.lft (line feature table)	SubclassRAT (route attribute table)
<subclass>.ljt (line join table)	SubclassSEC (section table)
<subclass>.aft (area feature table)	SubclassPAT (region attribute table)
<subclass>.ajt (area join table)	SubclassRXP (region-polygon file)
Primitive table mappings
Default names of VPF primitive tables	Coverage primitive tables
txt (text table)	txt (text file) txtsubclass1 (text subclass 1) txtsubclass2 (text subclass 2) textsubclass(n) (text subclass n)
end (entity node table)	lab (label file for points)
x_lab (extra label file)	lab (label for polygons)
cnd (connected node table)	arc (arc file) nat (node file)
edg (edge table) ebr (edge bounding rectangle table)	arc (arc file)
fac (face table) fbr (face bounding rectangle table) rng (ring table)	pal (polygon-arc-list file)

In addition to the ArcInfo feature tables created, the VPF to Coverage tool also creates code tables (in INFO) based on attributes from the VPF feature tables. If a column in a VPF feature table is a code reference to information stored in the Value Description Table (VDT), then a code table is created. The naming convention for the code tables is <Feature Class Table Name>.<Attribute>.

If the VPF data being imported has a spatial index for its primitive table, a spatial index will be built on that feature in ArcInfo.


Converting ArcInfo data into VPF

  Feature relationships
  Exporting to an existing VPF library
  INFO to VPF data type mapping
  VPF null information
  VPF coverage topology
  Using a conversion control file

Feature relationships

In a conversion driven by the Coverage to VPF tool, arcs become edges and polygons become faces; nodes become connected nodes and points become entity nodes. The ArcInfo feature attribute tables (e.g., PAT, AAT) become VPF feature tables (e.g., *.pft, *.lft). Simple ArcInfo features (points, lines, polygons, and text) are converted into VPF feature and primitive tables with a one-to-one relationship between the feature and primitive tables, with one exception:  the annotation text attribute tables (TATs) become one primitive table and as many feature tables as there are annotation subclasses in the coverage.

Features like regions and routes are converted into VPF feature tables and join tables with a many-to-many relationship to the associated primitive tables.

Exporting to an existing VPF library

VPF coverages

For an ArcInfo coverage to be converted to an existing VPF coverage, the projections of both coverages must match. (Projection information for the VPF coverage is stored in the GRT.) The features in newly converted ArcInfo coverages will be appended to the features in the existing VPF feature tables.

VPF tiles

Before an ArcInfo coverage can be exported to an existing VPF tile, the following must be true:

A tile reference coverage (which is a polygon coverage) must exist in the target VPF library. Some libraries in a VPF database may be tiled or untiled, but all the coverages in a given library must have the same tiling scheme, defined by a tile reference coverage stored in the library along with the coverages it applies to.

The tile being exported to must have a record in the feature table for the tile reference coverage (tileref.aft).The extent of the ArcInfo coverage being exported must fall on or within the extent of the specified VPF tile. If the extent of the ArcInfo coverage falls outside or partly outside that of the VPF tile, the Coverage to VPF tool will display an error message. (In that case, use ArcInfo LIBRARIAN to create an index coverage that matches the tiling scheme of the pertinent VPF library and tile the ArcInfo coverage using the newly created index coverage.)

A single ArcInfo coverage can be exported to a single VPF tile. If there is more than one tile in the VPF coverage, the Coverage to VPF tool must be executed once for each VPF tile.

The feature tables for the tile and library reference coverages must have specific names (i.e., tileref.aft and libref.lft). A default conversion does not create these names; to create them, specify them with the FEATURECLASS command (see below). In addition, the tile reference area feature table must be in the format specified by the VPF Defense standard.

No ArcInfo coverage to be exported can have a mask file; only Clean coverages will export.

In addition, a projection must be defined for an ArcInfo coverage before it can be converted, and the projection for all coverages in a given library must be the same.

INFO to VPF data type mapping

The table below indicates the default and valid INFO to VPF data type mappings. The default VPF data types can be changed by using the conversion control command ITEMBECOMES.

INFO-to-VPF data type mappings

     INFO data type	VPF data type

	F, short floating point	R,  long floating point	S,  short  integer	I,  long  integer	T,  text	D,  date and time
D, date	Valid	Valid	n/a	Valid	Valid	Default
C (n), character	Valid	Valid	Valid	Valid	Default	n/a
I (1 - 16), integer	Valid	Valid	Valid	Default	Valid	Valid
N (1 - 16), numeric	Default	Valid	Valid	Valid	Valid	Valid
B (2), binary	Valid	Valid	Default	Valid	Valid	n/a
B (4), binary	Valid	Valid	Valid	Default	Valid	n/a
F (4), short floating point	Default	Valid	Valid	Valid	Valid	n/a
F (8), long floating point	Valid	Default	Valid	Valid	Valid	n/a

Thematic index naming convention

A VPF thematic index is created for any item (column) in an INFO table that has an index built on it. The name of the thematic index is based on the INFO table type and item name, as follows:

INFO table type 	Thematic index name
Non-feature table	<column_name>.ti
Point feature table	<column_name>.pti
Line feature table	<column_name>.lti
Area feature table	<column_name>.ati
Text feature table	<column_name>.tti
Complex feature table	<column_name>.cti

VPF null information

All VPF items have a possible null value. In some cases, imported null VPF values cannot be represented in the INFO data model. For example, a null floating point which is imported into INFO cannot continue to be represented as a null. A set of default null values assure that data can be imported and exported correctly. Any null value found by the VPF to Coverage tool will be represented with the following values:

Default INFO null values (if VPF nulls are imported without a SET NULL statement.)
S	Short integer	-9999
I	Long integer	-999999
F	Short float	-999999
R	Long float	-999999

When the Coverage to VPF tool sees any of the above values, it will automatically export them back into VPF null values.

The SET NULL command (see Global Commands) allows the user to override the default behavior, and to remap the null values of specific VPF items into values that INFO can handle.

VPF coverage topology

The level of topology in a VPF coverage created by conversion is based on the topology level of the ArcInfo coverage, as follows:

VPF topology level will be 3 (full topology) if the ArcInfo coverage has polygon topology (i.e., if a polygon-arc list (PAL) file exists). The VPF primitives will be connected nodes, entity nodes, edges, and faces. The surface will be partitioned by a set of mutually exclusive and exhaustive faces, and edges will meet only at nodes.

VPF topology level will be 2 (planar graph) if the ArcInfo coverage has polygon topology but the polygons are ignored during conversion. The VPF primitives will be a set of connected nodes, entity nodes, and edges. When projected onto a planar surface, the edges meet only at nodes.

VPF topology level will be 1 (nonplanar graph) if the ArcInfo coverage has line topology with nonzero node numbers. As in level 2 topology, the VPF primitives will be a set of connected nodes, entity nodes, and edges, but when the edges are projected onto a planar surface, they may or may not meet at nodes.

VPF topology level will be 0 (boundary representation, informally known as spaghetti) if the ArcInfo coverage has line topology with zero node numbers, point topology, or both. The VPF primitives will be a set of edges and entity nodes; the edges will contain only coordinates, not start and end nodes.

Preserving ArcInfo information that doesn’t convert to VPF

When there is a one-to-one relationship between the feature and primitive tables, each contains a pointer to the other; that is -

The VPF feature table contains a primitive ID column that points to the related primitive row, and the VPF primitive table associated with the feature table contains a feature ID column that points to the related feature row.

Two tables are created specifically to preserve information that doesn’t convert: x_itmdef and x_lab. The x_lab table is created to contain ArcInfo polygon label points.

The Coverage to VPF tool creates a VPF table called x_itmdef, by default. The x_itmdef table is constructed to contain information about the item definitions in the original INFO table that has no relevance to VPF (whether the item was redefined, output width, etc.).

The primary objective of creating an x_itmdef table is to allow an INFO table to be returned to its original state after a double conversion (i.e., conversion from INFO to VPF to INFO).

A record is added to the x_itmdef table for each item in the original INFO table. Other records are added to contain information about the INFO table that would facilitate a double conversion, such as the INFO table name. The columns in the x_itmdef table are listed in the following table:

Columns in x_itmdef table for default table conversion
x_itmdef column	Description
id	Row ID
info_name	INFO table the INFO item belongs to
info_external	Indicates whether the INFO table is external
item_ignore	Indicates whether the item is ignored during Coverage to VPF
indexitem	Indicates whether the item is indexed
vpf_colname	Name of the corresponding column in the VPF table
item_name	INFO item name
width	INFO item width
key_type	INFO key type
position	INFO item starting position
protect_level	INFO protection level
display_width	INFO item output width
decimal_place	Number of decimal places for item
item_type	INFO item type
access	Indicates read-only access
key_level	INFO key level
index	INFO index number
occurrence	INFO occurrence count
alternate_name	INFO alternate name
concordance	INFO concordance level
alternate_rule	Alternate item naming rule
concord_case	Concord case
concord_number	Concord numbers
logical_index	Logical item number; -1 if INFO item was redefined
key_count	Number of duplicate keys allowed
Using a conversion control file

  Conversion control file structure
  EXPORT structure
  Global commands
  Primitive commands
  Feature commands
  Conversion control file examples

A conversion control file with the Coverage to VPF tools’s Cover option allows you to alter the structure and content of the VPF database, library, coverage, tiles, and tables. For example, a conversion control file can be used to ignore specified feature classes during translation, and it can be used to set the values in the database and library header files when they are created.

Conversion control file structure

The conversion control file (CCF) has two major sections: EXPORT and IMPORT. The IMPORT section of the CCF controls the conversion of VPF data into ArcInfo. The EXPORT section of the CCF controls the conversion of ArcInfo data into VPF. The file is structured as follows:

EXPORT                     /* Begins EXPORT section.
global commands            /* Affects all tables being imported.
primitive command block    /*Alters primitive tables.
featureclass command block /* Controls ArcInfo feature class.
END                        /* Ends EXPORT section.
IMPORT                     /* Begins IMPORT section.
global commands            /* Affects all tables being exported.
END                        /* Ends IMPORT section.

The file can also contain any number of comment lines, which begin with the characters /*.

EXPORT structure

When a coverage is converted, the EXPORT section of the conversion control file may (but is not required to) have three subsections: global commands, primitive commands, and feature commands. Each subsection may contain any number of commands; and each ends with the beginning of the next EXPORT subsection, the beginning of the IMPORT section, or the end of the conversion control file (as indicated by END). The structure of the EXPORT section for a coverage is illustrated below. (A primitive or feature class block is a set of commands that pertains to a single primitive or feature class.)

Global commands

Global commands affect certain characteristics of the VPF tables, coverages, libraries, and databases.

IGNORE <item1>.... {item9} - ignores INFO items during translations. Up to nine items may be given on any one ignore statement. Once an INFO item is ignored, the data will be lost during the translation to VPF, and will not be regained when using the VPF to Coverage tool.

CREATE NARRATIVE <level> <table> <text_file> {textwidth} (description} - converts input ASCII text file into a VPF narrative table.

SET <table> <column> <value> - sets a VPF table column to a specific value.

SET NARRATIVE <vpf_table> <narrative_name> {level} - specifies a narrative table to be associated with a VPF table.

SET DESCRIPTION <vpf_table> <description> {level} - specifies a description string associated with a VPF table.

SETVDT <vpf_table | Null> <item_name> <info_table> - creates the specified VDT table for the coverage from an INFO lookup file with a predefined format.

SETBYTEORDER <least | most> - sets the byte order for all of the VPF tables converted.

SET NULL <vpf_table> <item> <info_null_value> - allows the user to predefine a VPF null value in ArcInfo.  For example, the user might define "-9" as a VPF null for a specific item in a specific VPF table upon export. When exported into VPF, the records with "-9" in the specified item will be converted to the appropriate VPF null for that item type.

SET COVDESC <description> - specifies the description used for the coverage in the Coverage Attribute Table (CAT).

NOCAT - specifies that this coverage should not be added to the Coverage Attribute Table.

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession. When used in the global section, this command will only work using the TABLE option.

Primitive commands

Primitive commands begin with the PRIMITIVECLASS command, which identifies the VPF primitive type affected by subsequent commands.

PRIMITIVECLASS < CND | END | EDG | FAC | RNG | TXT | EBR | FBR > (respectively, connected nodes, entity nodes, edges, faces, rings, text, edge bounding rectangles and face bounding rectangles).

ITEMBECOMES <item> <column> {col_type) (count} {keytype} {description} {vdt} {thematic_index} {narrative}

IGNORE <item1> {item2}............{item9} - ignores specified columns in the ArcInfo primitive table when the conversion takes place (IGNORE). (Columns required by VPF cannot be ignored, however.)

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession.

Feature commands

Feature commands begin with the FEATURECLASS command, which identifies the ArcInfo feature class affected by subsequent commands. This section describes the FEATURECLASS command syntax and functions.

FEATURECLASS <arc_feature_class> {feature_table | IGNORE} {description} {info_table | ONE} - allows you to specify an ArcInfo feature class to be ignored during conversion; to rename, describe, and specify the INFO table that serves as the source for the VPF feature table; to create complex features; and to force a one-to-one relationship between the features and primitives in the route and region feature classes.

<arc_feature_class> - valid feature classes are: ARC, NODE, POINT, POLY, ANNO.subclass, ROUTE.subclass, REGION.subclass, SECTION.subclass, COMPLEX.  See the Creating complex features section below for a description of COMPLEX.

{feature_table | IGNORE} - either renames the VPF table to be created or ignores the specified <arc_feature_class> during conversion.

{description} - specifies the description for the VPF feature table.

{info_table | ONE} - specifying an info_table name in this argument creates a VPF feature table directly from the INFO table specified.

ADDCOLUMN <column> <col_type> <count> <keytype> {description} {vdt} {thematic_index} {narrative}

ITEMBECOMES <item> <column> {col_type} {count} {keytype} {description} {vdt} {thematic_index} {narrative} - VPF column definition for an INFO item.

IGNORE <item1> {item2...item3} - ignores INFO items.

GROUPBY <column> - only valid within a FEATURECLASS block when an {info_name} has been specified. When converting, the specified column in the INFO table becomes the ID of the VPF feature. This groups all records with the same value for the column into a single record (a single feature).

JOIN <vpf_table> <info_table>

SCHEMA {table1} {key1} {table2} {key2}

ITEMORDER <item1>....{item9} - allows the user to modify the item order of a table upon export. All items must be represented within this command section in order for the items to be ordered correctly. If the user has more than 9 items, multiple ITEMORDER lines can be used in succession.

Creating complex features

Complex VPF features may be created by specifying COMPLEX as the <arc_feature_class>. For example, the command below:

FEATURECLASS COMPLEX airport.cft ‘Airports’ airport.ftr

creates a complex VPF feature table with the name 'airport.cft' and a description of airports from the INFO table airport.ftr.

When COMPLEX is used, defining feature-to-feature and feature-to-primitive relationships is the responsibility of the user. For that reason, FEATURECLASS commands that specify a COMPLEX feature class should be followed by SCHEMA commands and any necessary JOIN commands.

Conversion control file examples

The first example is a conversion control file that is used to export a single INFO table. The control file starts by defining the table name. If the table exported has the name 'polbndl.lft', then the SET DESCRIPTION line will be invoked. If the table is exported under a different name, then the SET DESCRIPTION line will be ignored. The ITEMBECOMES lines control how the INFO items will be exported.

/************
EXPORT
TIDX_TYPE ALL LONG
SETBYTEORDER LEAST
SET DESCRIPTION polbndl.lft 'Political Boundary Line Feature Table'
ITEMBECOMES id id I 1 P 'Row Identifier' # # #
ITEMBECOMES f_code f_code T 5 N 'FACC Feature Code' char.vdt f_code3.lti #
ITEMBECOMES acc acc S 1 N 'Accuracy Category' int.vdt # #
ITEMBECOMES bst bst S 1 N 'Boundary Status Type' int.vdt # #
ITEMBECOMES nm3 nm3 T * N 'Name3' char.vdt # nm3_1.doc
ITEMBECOMES nm4 nm4 T * N 'Name4' char.vdt # nm4_1.doc
ITEMBECOMES txt txt T * N 'Text Attribute' char.vdt # #
ITEMBECOMES use use S 1 N 'Usage' int.vdt # #
ITEMBECOMES tile_id tile_id S 1 N 'Tile Reference ID' # tile3_id.lti #
ITEMBECOMES edg_id edg_id I 1 N 'Edge Primitive ID' # edg3_id.lti #
/************

The next example is a conversion control file that is used to export an ArcInfo net coverage into a VPF coverage.

/************
/*** Global Section
EXPORT

SET COVDESC 'Elevation'
SETBYTEORDER least

SET DESCRIPTION ebr 'Bounding Rectangle Table'
SET DESCRIPTION fbr 'Bounding Rectangle Table'

SET DESCRIPTION cnd.fit 'Feature Index Table'
SET DESCRIPTION edg.fit 'Feature Index Table'
SET DESCRIPTION fac.fit 'Feature Index Table'

CREATE NARRATIVE COVERAGE  contourl.doc %.vpfdocs%/elev-contourl
SET NARRATIVE contourl.lft contourl.doc

/** Primitive Section begins here

/** Here we define all out Primitive classes and their appropriate
/** descriptions.
/** (All of the information needed to create these CCFs should be
/** found in the VPF Product Specification.)

PRIMITIVECLASS CNDFIT
  ITEMBECOMES ID id I 1 P 'Row Identifier'
  ITEMBECOMES PRIM_ID prim_id I 1 N 'Primitive ID' # cnd_fit1.fti
  ITEMBECOMES TILE_ID tile_id S 1 N 'Tile Reference ID'  # cnd_fit2.fti
  ITEMBECOMES FC_ID fc_id I 1 N 'Feature Class ID' # cnd_fit3.fti
  ITEMBECOMES FEATURE_ID feature_id I 1 N 'Feature Table ID' # cnd_fit4.fti

PRIMITIVECLASS EDGFIT
  ITEMBECOMES ID id I 1 P 'Row Identifier'
  ITEMBECOMES PRIM_ID prim_id I 1 N 'Primitive ID' # edg_fit1.fti
  ITEMBECOMES TILE_ID tile_id S 1 N 'Tile Reference ID'  # edg_fit2.fti
  ITEMBECOMES FC_ID fc_id I 1 N 'Feature Class ID' # edg_fit3.fti
  ITEMBECOMES FEATURE_ID feature_id I 1 N 'Feature Table ID' # edg_fit4.fti

PRIMITIVECLASS FACFIT
  ITEMBECOMES ID id I 1 P 'Row Identifier'
  ITEMBECOMES PRIM_ID prim_id I 1 N 'Primitive ID' # fac_fit1.fti
  ITEMBECOMES TILE_ID tile_id S 1 N 'Tile Reference ID'  # fac_fit2.fti
  ITEMBECOMES FC_ID fc_id I 1 N 'Feature Class ID' # fac_fit3.fti
  ITEMBECOMES FEATURE_ID feature_id I 1 N 'Feature Table ID' # fac_fit4.fti

PRIMITIVECLASS cnd
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES first_edge first_edge I 1 N 'Foreign Key to Edge Table'
  ITEMBECOMES coordinate coordinate Z 1 N 'Coordinates of Connected Node'
  IGNORE cpoint.pft_id containing_face

PRIMITIVECLASS edg
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES start_node start_node I 1 N 'Start/Left Node'
  ITEMBECOMES end_node end_node I 1 N 'End/Right Node'
  ITEMBECOMES right_face right_face K 1 N 'Right Face'
  ITEMBECOMES left_face left_face K 1 N 'Left Face'
  ITEMBECOMES right_edge right_edge K 1 N 'Right Edge from End Node'
  ITEMBECOMES left_edge left_edge K 1 N 'Left Edge from Start Node'
  ITEMBECOMES coordinates coordinates Z * N 'Coordinates of Edge'
  ITEMBECOMES contourl.lft_id contourl.lft_id I 1 N 'Line Feature Table ID'
  ITEMBECOMES depthl.lft_id depthl.lft_id I 1 N 'Line Feature Table ID'

PRIMITIVECLASS rng
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES face_id face_id I 1 N 'Foreign Key to Face Table'
  ITEMBECOMES start_edge start_edge I 1 N 'Foreign Key to Edge Table'

PRIMITIVECLASS fac
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES ring_ptr ring_ptr I 1 N 'Foreign Key to Ring Table'
  ITEMBECOMES elevoida.aft_id elevoida.aft_id I 1 N 'Area Feature Table ID'

PRIMITIVECLASS fbr
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES xmin xmin F 1 N 'Minimum X Coordinate'
  ITEMBECOMES ymin ymin F 1 N 'Minimum Y Coordinate'
  ITEMBECOMES xmax xmax F 1 N 'Maximum X Coordinate'
  ITEMBECOMES ymax ymax F 1 N 'Maximum Y Coordinate'

PRIMITIVECLASS ebr
  ITEMBECOMES id id I 1 P 'Row Identifier'
  ITEMBECOMES xmin xmin F 1 N 'Minimum X Coordinate'
  ITEMBECOMES ymin ymin F 1 N 'Minimum Y Coordinate'
  ITEMBECOMES xmax xmax F 1 N 'Maximum X Coordinate'
  ITEMBECOMES ymax ymax F 1 N 'Maximum Y Coordinate'

/** Feature Section begins here

/** A technique is used which converts single INFO tables instead
/** of whole feature classes. The INFO tables consist of selected
/** features with selected items (much like routes/regions, but
/** without the topology). These INFO tables are converted instead
/** of the main PAT and AAT.

/** This allows the user to have multiple feature classes of the same
/** type (instead of the one AAT feature class, or one PAT feature class.)

/** In order to make this work correctly, we must ignore all current
/** feature classes so they don't get converted to the defaults. (Then we
/** define one feature class at a time). If we decide to use this method,
/** we are  responsible for stating our own schema statements. (Schema
/** statements  are usually created automatically if ArcInfo understands the
/** Primitive->feature relationship, like in default POLY or LINE conversion)

FEATURECLASS ARC IGNORE
FEATURECLASS POLY IGNORE
FEATURECLASS NODE IGNORE
FEATURECLASS POINT IGNORE
FEATURECLASS ANNO IGNORE
FEATURECLASS ANNO.VPF IGNORE

FEATURECLASS ARC contourl.lft 'Contour Line Feature Table' contourl.lfd
   ITEMBECOMES ID id I 1 P "Row Identifier"
   ITEMBECOMES ELEVNET# edg_id I 1 N "Edge Primitive ID" # edg1_id.lti
   ITEMBECOMES F_CODE f_code T 5 N 'FACC Feature Code' char.vdt
   ITEMBECOMES ZV2 zv2 S 1 N 'Highest Z-value (meters)' int.vdt
   ADDCOLUMN tile_id S 1 N 'Tile Reference ID' # tile1_id.lti
   SCHEMA contourl.lft edg_id edg id
   SCHEMA edg contourl.lft_id contourl.lft id

FEATURECLASS ARC depthl.lft 'Depth Line Feature Table' depthl.lfd
   ITEMBECOMES ID id I 1 P "Row Identifier"
   ITEMBECOMES ELEVNET# edg_id I 1 N "Edge Primitive ID" # edg2_id.lti
   ITEMBECOMES F_CODE f_code T 5 N 'FACC Feature Code' char.vdt
   ITEMBECOMES ACC acc S 1 N 'Accuracy Category' int.vdt
   ITEMBECOMES CRV crv S 1 N 'Depth Curve or Contour Value (meters)' int.vdt
   ADDCOLUMN tile_id S 1 N 'Tile Reference ID' # tile2_id.lti
   SCHEMA depthl.lft edg_id edg id
   SCHEMA edg depthl.lft_id depthl.lft id

FEATURECLASS POLY elevoida.aft 'Elevation Void Collection Area Feature Table' elevoida.afd
   ITEMBECOMES ID id I 1 P "Row Identifier"
   ITEMBECOMES ELEVNET# fac_id I 1 N "Face Primitive ID" # fac1_id.ati
   ITEMBECOMES F_CODE f_code T 5 N 'FACC Feature Code' char.vdt
   ITEMBECOMES VCA vca S 1 N 'Void Collection Attribute' int.vdt
   ADDCOLUMN tile_id S 1 N 'Tile Reference ID' # tile1_id.ati
   SCHEMA elevoida.aft fac_id fac id
   SCHEMA fac elevoida.aft_id elevoida.aft id

END
/************


ArcInfo to VPF conversion procedures

This section describes one methodology that can be used to convert an ArcInfo database into a VPF-compliant, product-specific database.

  Coverage processing
  Feature table processing
  The VPF translation process
  QC of the VPF database

Coverage processing

Any topologically correct ArcInfo coverage can be converted into a VPF formatted coverage using the Coverage to VPF tool. The typical VPF product, however,  will probably require some pre-processing of the ArcInfo data before translation in order to meet the particular specifications of that product.

Tiling the ArcInfo database

Tiling is the partitioning of geographic data spatially into subsets of manageable size. If the VPF database is to be stored in a tiled format, then the ArcInfo database must also be tiled before it is translated. This can be accomplished by using ArcInfo’s LIBRARIAN program to build a map library. Once the library data structure has been built, then the original ArcInfo coverages  can be inserted into the library which divides the data into separate tiled workspaces.

QC of the tiled ArcInfo database

Verify that the data has been inserted properly.

In order to insure that the LIBRARIAN INSERT command has properly inserted the data into the appropriate tiled workspaces, ARCPLOT can be used to compare a layer of tiled coverages with the original untiled coverage. A correctly inserted library layer will correspond perfectly to the untiled coverage within the established fuzzy tolerance.

Check for topological errors

After confirming that the data is present in the tiled workspaces, make sure that the inserted data is topologically correct. ArcInfo commands such as DESCRIBE, LABELERRORS, and NODEERRORS are useful for insuring that a coverage is “built” with the proper topology, that it is in the proper map projection, that all polygon features have labels, and that it contains no extraneous “dangling” arcs. If topological errors are not corrected before translating the data into VPF format, they will be reflected in the VPF database.

Build spatial indices

If spatial indices are required for the VPF product specification, then they need to exist for the ArcInfo coverages before they are translated. The ArcInfo command INDEX, which will build these spatial indices, should be implemented after the final use of the Build tool, since this latter command will erase any existing spatial index when rebuilding a coverage’s topology.

Feature table processing

Some VPF product specifications require that coverage features be divided into separate tables based on theme. For example, a transportation coverage might contain separate feature tables for roads, bridges, railroads, and ferry lines. These multiple feature tables must be built for the corresponding ArcInfo coverages before translation takes place. There are two different approaches to building these tables.

Restructuring feature attribute tables

One approach is to add and code all needed attributes to the coverage’s Feature Attribute Table (FAT), and then use INFO processing techniques (PULLITEMS, RESELECT, and PURGE) to split the FAT into smaller thematically unified INFO tables. These small feature tables would be used in place of the coverage.FAT when translating coverage features into VPF format. Any VPF join tables needed to link feature tables to primitive tables would have to be built as INFO tables first.

Routes, regions and annotation

A second approach is to split coverage features into subclasses and then add and code attributes to each subclass FAT. Routes, Regions, and Annotation feature class types provide for multiple subclasses within a coverage. For example, a transportation coverage might contain route subclasses for roads, bridges, railroads, and ferry lines. Additionally, Routes and Regions allow for many to many relationships between arcs and line features or polygons and area features, respectively. The Coverage to VPF tool will convert these feature subclasses by default into separate VPF feature tables without any additional INFO processing. Join tables linking the feature tables to the primitive tables are automatically created for each Route or Region subclass. There is no equivalent of the Route or Region feature class type for point features in ArcInfo. Multiple feature tables for point coverages must be created using the restructure method.

Additional tables

A VPF product specification may require tables in addition to the primitive and feature tables and the metadata tables automatically created by the Coverage to VPF tool (FIT tables, FCS, FCA). Value Description Tables (VDTs), complex feature tables, related attribute tables (RATs), and narrative tables are all possible VPF data structures. With the exception of narrative tables, these additional tables must be created or loaded into the INFO format. Narrative tables should be in ASCII format.

The VPF translation process

ArcInfo data can be converted into VPF formatted data using the Coverage to VPF tool. If the tool is executed with all the default options, the resulting data will be compliant to the VPF standard, but it will probably not meet all the requirements of a typical VPF product. Through the use of the conversion control file (CCF), different options to the tool can be utilized so that translated data will conform to the product specifications.

Creating conversion control files

The VPF Defense Standard is a flexible digital data format that allows for wide variation between products. The conversion control file (CCF) is an text file containing any number of VPF specific statements that allows the user to control the large number output options inherent in such a flexible format. There are dozens of valid CCF statements that can be used to customize a VPF database. Typically, a separate conversion control file is created for each ArcInfo coverage or library layer. With a few exceptions, most of the additional tables (VDTs, etc) associated with a coverage can be converted along with the coverage’s primitive and feature tables by including the appropriate statements in the CCF for that coverage. The exceptions, such as most related attribute tables, will have to be converted separately with their own CCF using the Coverage to VPF tool with the Table option.

Conversion of the Tileref coverage

If the VPF product is to consist of tiled data, then the tile reference coverage (TILEREF) must be the first VPF coverage created because the translater uses this coverage’s tiling scheme to create tile workspaces for the tiled coverages. The INDEX coverage for the ArcInfo map library is generally used as the input coverage since it serves an analogous purpose for the ArcInfo library. Because TILEREF is the first coverage converted for each VPF tiled library, its CCF should contain the appropriate statements to generate the library level metadata tables (LHT, GRT). If it is also the first coverage converted for the entire database, then the CCF should also include statements for the database level metadata (DHT).

Conversion of the tiled data

Once the TILREF coverage has been created, the tiled ArcInfo coverages can be converted. Each tile workspace where data for a library layer is present needs to be converted. This can be done using the batch mode of the Coverage to VPF tool. The CCF for each coverage should explicitly state which tables and table columns should be converted and which ones should be ignored because if it is not mentioned in the CCF it will generally be converted with default parameters.

Conversion of additional tables

Any tables associated with a coverage that are not converted along with the primary coverage files (feature tables, primitive tables, etc.), must be converted separately using the Coverage to VPF tool with the Table option.

QC of the VPF database

Each coverage should be checked for attribute accuracy and topological validity once it has been converted to VPF format. ArcInfo provides the command VPFLIST which displays VPF formatted tables, and the NIMA’s query tool, VPFVIEW, allows the user to graphically view VPF data. However, analytical tools to test topological relationships between tables and to provide summary statistics are not part of the standard ArcInfo package. These tools are available from ESRI with a services contract, or the user can build these tools in-house.

Build cross-tile topology

Connectivity of features between tiles is a requirement of the VPF Defense Standard, but the Coverage to VPF tool does not create cross-tile topolgy for a VPF coverage. After all the tiles for a coverage has been converted, then the Create VPF Tile Topology tool can be implemented to build topology between edge and face primitives that connect at tile boundaries.


Converting SDTS data

The Spatial Data Transfer Standard (SDTS) is a data exchange format for transferring different databases between dissimilar computing systems, preserving meaning and minimizing the amount of external information needed to describe the data. In the future, all Federal digital map data will be made available upon request in SDTS format. SDTS is documented in FIPS publication 173 available from the U.S. Department of Commerce.


The SDTS data structure

SDTS supports all types of spatial data including vector data structures, with and without topology; raster data, both gridded and image; data with different coordinate systems; data with different attribute models; and data with different graphic representations.

Because SDTS supports so many types of data , the standard is broken up into smaller subsets of options specific to a particular data type. These limited subsets of the SDTS options are called profiles. Each profile is an approved Federal Information Processing Standard in itself. The first profile to be approved and the only profile supported by the Import SDTS Wizard and the Export to SDTS tool is the Topological Vector Profile, (TVP) designed specifically for topologic vector data with geometry.

SDTS transfer files are like ArcInfo coverages, consisting of modules which are physical files. Each module, formatted as specified by Part 3 of the SDTS standard and ISO 8211, consists of one or more records. Each record consists of one or more fields. Each field consists of one or more sub-fields. The individual data items are carried by the sub-fields. The modules come in three groupings, Global, Data Quality, and Spatial Objects. The Global Information Modules define global parameters for interpreting the data transfer. The Data Quality modules contain information on the quality of the transferred data. Spatial Object modules include the locational, topologic, and attribute information for the data set. Not all files will be included in all data sets; see Part 4 of the SDTS standard for a complete list of the required modules.

SDTS Modules

Module	Module Type	Primary Field Name	Mnemonic
Global	Identification		IDEN
	Catalog	Directory	CATD
		Cross-Reference	CATX
		Spatial Domain	CATS
	Spatial Reference	Internal	IREF
		External	XREF
		Spatial Domain	SPDM
	Data Dictionary	Definition	DDDF
		Domain	DDOM
		Schema	DDSH
	Security		SCUR
	Transfer Statistics		STAT
Data Quality		Lineage	DQHL
		Positional Accuracy	DQPA
		Attribute Accuracy	DQAA
		Logical Consistency	DQLC
		Completeness	DQCG
Spatial Objects	Composite		FFnn
	Vector modules	Point-Node
		NP - Point	NPnn
		NL - Label point	NLnn
		NE - Entity point	NEnn
		NA - Area point	NAnn
		NO - Node, planar	NOnn
		Line
		LE - Complete chain	LEnn
		Polygon
		PC - GT-polygon chains	PCnn
		PW - Universe poly chains	PWnn
		PV - Void polygon	PVnn
		PX - Void polygon chains	PXnn
Attribute	Primary		Annn
	Secondary		Bnnn


Creating coverages from an SDTS transfer

  SDTS data products
  The Master data dictionary
  Multiple spatial objects and complex spatial objects

SDTS data products

The Import SDTS Wizard can read the U.S. Bureau of the Census TIGER and U.S. Geological Survey DLG-3 data in SDTS format as well as other data sets compliant with the SDTS Topological Vector, Raster or Point profiles. All SDTS transfers adhere to the following naming conventions. The files in a transfer all begin with the same four character prefix followed by a valid module name. In most cases the module name is a four character mnemonic (see table on SDTS modules). For spatial objects, it is normally one or two characters followed by a sequence number, nnn, or nn respectively. The transfer file names may contain both alpha and numeric characters. All characters are in uppercase. The Import SDTS Wizard is case sensitive.

Most transfers will be distributed in separate directories. It is common for USGS DLG-3/SDTS files for example, to use mixed case directory names. Most ArcToolbox tools will not accept pathnames with directories named this way but the Import SDTS Wizard will accept them as long as the directory name is included in the pathname you specify with the transfer prefix.

Please note that you should not use the Import SDTS Wizard to create a new coverage located in the transfer directory. If the directory name contains upper case characters, the wizard will be unable to verify your current workspace, and will fail.

The Master data dictionary

There is a fair amount of global or metadata information that may apply to several transfers. When there are multiple transfers that share this same information it is often distributed separately in a directory called "masterdd", referred to as a master data dictionary. The following is the listing of a directory DLG3 containing seven DLG-3/SDTS transfers and a master data dictionary.

CraterLakeHP	FalmouthTR	SSMarieHY	SedaliaHY
FalmouthHY	MilanTR	SSMarieTR	masterdd

The MASTERDD directory contains the following:

DLG3.VER	DLG3MDIR.DDF	DLG3MIDE.DDF	DLG3MQCG.DDF
DLG3MDEF.DDF	DLG3MDOM.DDF	DLG3MQCG.DDF	README

If the masterdd is located at the same directory level as the transfer directory, Import SDTS Wizard will automatically convert the SDTS transfer using the global information found in the masterdd. If the masterdd directory is missing or if you copy your transfer directory to a different location on your system, Import SDTS Wizard will still convert but the output will not contain this metadata information. If you do not have a masterdd directory with the SDTS transfer data you receive, then the modules of the master data dictionary are probably included in the transfer directory and will be converted with the rest of the transfer information. If your transfer does not contain the global modules, Import SDTS Wizard will issue a warning message indicating which modules are missing and continue to convert your dataset.

Multiple spatial objects and complex spatial objects

The SDTS spatial data model can be made up of more than one spatial object referred to as aggregated spatial objects which can be more easily thought of as data layers. The DLG-3/SDTS transfers may contain several different layers of spatial data that should be converted into separate coverages. These layers may overlap or may be adjacent to one another.

When you convert an aggregated spatial object or data layer, polygon and line topology are generated. Complex spatial object modules are converted to either regions or route/sections depending on the spatial object type. Related attribute tables are written to the output coverage. The relate environment is stored in <Line coverage>.REL and <Point coverage>.REL if it is created. An additional cross-reference table <Line coverage>.RELX will be written to store both the from and to table information for all related attribute tables. Attribute tables will be named with either <Line coverage> or <Point coverage> prefix and either APnn or ASnn extensions. Region and Route subclasses will be named with FFnn extensions.

The following is a listing of the TIGER/SDTS transfer files for Ohio, IN. The four-character file prefix is 2500.

2500AP02.DDF	2500AP35.DDF	2500DDOM.DDF	2500NE00.DDF
2500AP08.DDF	2500AP37.DDF	2500DDSH.DDF	2500NO00.DDF
2500AP09.DDF	2500AP38.DDF	2500DQAA.DDF	2500PC00.DDF
2500AP11.DDF	2500AP39.DDF	2500DQCG.DDF	2500SPDM.DDF
2500AP12.DDF	2500AP40.DDF	2500DQHL.DDF	2500STAT.DDF
2500AP14.DDF	2500AP41.DDF	2500DQLC.DDF	2500XREF.DDF
2500AP16.DDF	2500AP42.DDF	2500DQPA.DDF	2500AP23.DDF
2500AP17.DDF	2500AP43.DDF	2500FF00.DDF	2500XREF.DDF
2500AP18.DDF	2500AP44.DDF	2500FF01.DDF	2500IREF.DDF
2500AP19.DDF	2500AP46.DDF	2500FF02.DDF	2500IREF.DDF
2500AP20.DDF	2500AP47.DDF	2500FF03.DDF	2500SPDM.DDF
2500AP21.DDF	2500AP48.DDF	2500FF04.DDF
2500AP22.DDF	2500AP49.DDF	2500FF05.DDF
2500AP24.DDF	2500AP50.DDF	2500FF06.DDF
2500AP25.DDF	2500AP53.DDF	2500FF07.DDF
2500AP26.DDF	2500AP55.DDF	2500FF08.DDF
2500AP27.DDF	2500AP57.DDF	2500FF09.DDF
2500AP28.DDF	2500AP58.DDF	2500FF10.DDF
2500AP31.DDF	2500CATD.DDF	2500IDEN.DDF
2500AP32.DDF	2500CATS.DDF	2500IREF.DDF
2500AP33.DDF	2500CATX.DDF	2500LE00.DDF
2500AP34.DDF	2500DDDF.DDF	2500NA00.DDF


Creating an SDTS (TVP) transfer from a coverage

The Topological Vector Profile (TVP), which was designed specifically for planar vector data with topology, is one of the profiles supported by the Export to SDTS tool.

The ArcInfo coverage must not have a mask file, only clean coverages will export. The ArcInfo coverage must have projection defined or it will not be exported. The Input coverage must have polygon topology. It may also be built for lines and nodes and may contain regions and routes. All items in the PAT and all items in the optional AAT, NAT, and region and route subclasses will be written to the transfer as attribute primary modules with direct links to their corresponding spatial object modules.

All other attribute tables with the same Input coverage or in Input point coverage prefix will be written to the transfer as attribute secondary modules. If either <Input coverage>.REL or <Input point coverage>.REL relate tables exist, they will not only be written out as secondary attributes but will also be used in global modules to provide more information to the receiving system about table relationships. Log and tolerance files will be written to the SDTS transfer as well.

Step 1: Clean coverage

The coverage must be clean to export. Run the Clean tool if MSK files exist in the coverage directory.

Step 2: Build coverage

Use the Build tool to create polygon topology if it does not already exist. In addition it may also be built for Line, Node, Region, and Route. All built topology will be written to the SDTS transfer.

Step 3: Create coverage relate table (optional)

Create a relate table named <Input coverage>.REL. The optional point cover may also include a relate table.

Step 4: Add projection to coverage

A PRJ file is required. If it does not exist, use the Define Projection Wizard to create it.

Step 5: Convert coverage

Run the Export to SDTS tool.

Resulting SDTS (TVP) transfer files:

MMMMAF00.DDF	MMMMCATD.DDF	MMMMDQLC.DDF	MMMMNO01.DDF	MMMMAF01.DDF	MMMMCATS.DDF	MMMMDQPA.DDF	MMMMNP01.DDF	MMMMAF03.DDF	MMMMCATX.DDF	MMMMFF00.DDF	MMMMPC01.DDF	MMMMAPID.DDF	MMMMDDDF.DDF	MMMMFF01.DDF	MMMMSPDM.DDF	MMMMAPLE.DDF	MMMMDDOM.DDF	MMMMFF03.DDF	MMMMSTAT.DDF	MMMMAPNO.DDF	MMMMDDSH.DDF	MMMMIDEN.DDF	MMMMXREF.DDF	MMMMAPNP.DDF	MMMMDQAA.DDF	MMMMIREF.DDF	MMMMAPPC.DDF	MMMMDQCG.DDF	MMMMLE01.DDF	MMMMAXRF.DDF	MMMMDQHL.DDF	MMMMNA01.DDF


Supported data exchange formats

The ArcToolbox includes many tools for converting data. The tools transfer data into and out of ArcInfo from several sources, including other mapping systems, scanned data, satellite images, and other cell-based data.

This chapter simply summarizes the different formats supported and the tools that convert them. For more detailed descriptions, refer to the help on individual tools and the chapters on data conversion issues

  Supported vector formats
  Supported image formats
  Converting images
  Converting grids
  Converting DTED data
  Grids as lattices
  Converting latiices to other formats
  Creating tins


Supported vector formats

The following file formats generated by other mapping systems can be converted into ArcInfo coverages. Most data translators are bi-directional, that is ArcInfo coverages can be written out to the same format they were created from. Refer to the tool help for details and instructions on using these data translators.

Digital Feature Analysis Data (DFAD) - developed by National Imagery and Mapping Agency (NIMA) for use in aircraft flight simulators. NIMA distributes DFAD data to various federal and commercial military systems developers including the Defence Intelligence Agency and the U.S. Army Topographic Engineering Center. The DFAD converter will provide both federal and commercial NIMA mapping sites with an important tool for updating. All four DFAD data products are supported by the Version 7 DFAD converter.

 Level 1 - generally 1:250,000 scale data
 Level 2 - generally 1:50,000 scale data
 Level 1-C - generally 1:250,000 scale data
 Level 3-C - generally 1:50,000 scale data

The NIMA DLMS culture file format must be the 6/602 variety. Each DFAD file contains a series of data sets representing manuscripts.The DFAD to Coverage tool converts a DFAD file containing these manuscripts into an ArcInfo workspace with an output coverage generated for each manuscript. One manuscript may convert to two separate coverages if it contains polygon information. Complex header information is written to INFO files associated with each output coverage. The Coverage to DFAD tool converts back to a DFAD file.

Dual Independent Map Encoding (DIME) - the digital version of the U.S. Census Bureau’s Metropolitan Map Series, with address ranges and geographic codes. Address ranges are given for the left and right sides of the arc. GBF/DIME files usually cover the central city and contiguous populated areas of a Metropolitan Statistical Area. Each record contains the coordinates for a line segment in either latitude/longitude decimal degrees or State Plane coordinates. The from- and to-node numbers for each feature are also stored.

Digital Line Graph (DLG) - geographic data files provided by the Earth Science Information Center of the U.S. Geological Survey. These data files include information in two formats from the USGS planimetric map base categories such as transportation, hydrography, contours, and public land survey boundaries. Both optional and standard formats can be converted to ArcInfo coverages, but only the optional distribution format can be written.

STANDARD - (144 bytes per record) intended to minimize storage requirements.

OPTIONAL - (80 bytes per record) containing linkages for line, node, and area features, usually in meters, in the UTM coordinate system.

AutoCAD Drawing Interchange File (DXF) - the standard interchange format used by most CAD systems. AutoCAD DXF files contain entities organized into layers of related drawing information in either ASCII or binary format. AutoCAD Releases 9, 10, 11, 12 and 13(only ASCII) are supported.

Etak MapBase file - A digital street network ASCII file available from Etak, Inc., similar in content to the GBF/DIME format used by the U.S. Census Bureau and the U.S. Geological Survey. It has a fixed length record format suitable for data exchange on magnetic tape. Unlike GBF/DIME files, Etak files also store points that define the shape of each linear feature in addition to from- and to-nodes.

Interactive Graphic Design Software (IGDS) - the interchange format for Intergraph Microstation software. Commonly referred to as design files or DGN files and composed of a series of levels, each level containing one or more drawing elements in binary format. Elements may have attribute linkages pointing to attribute tables.

Initial Graphics Exchange Standard (IGES) - the IGES version 3.0 format, published by the U.S. Department of Commerce, in uncompressed ASCII format only. This format is often used to transfer CAD data between systems.

MOSS export file - an ASCII format file readable by the U.S. Department of Interior’s MOSS public domain GIS. The file contains points, lines, or closed polygon loops (possibly with islands) and a 30-character attribute field, called the subject value.

Spatial Data Transfer Standard (SDTS) - Federal Information Processing Standard 173 is a National standard for data exchange used by U.S. Federal agencies to make data available to state and local government as well as the general community. It was designed to transfer databases between different computing systems while preserving meaning and minimizing the need for external information describing the data. It supports all types of spatial data, including vector data structures, with and without topology; raster data, both gridded and image; data with different coordinate systems; data with different attribute models; and data with different graphic representations.

Shapefiles - the concept of shapefiles was adopted in ArcView 2 to allow limited editing of theme information. Shapefiles can be created in ArcView by screen digitizing lines, points, or polygons optionally attaching attributes and storing as a new theme or by writing a currently selected set of features and associated attributes in a theme to a shapefile. Shapefile spatial and attribute information can be edited in ArcView. Shapefiles include a file containing spatial information, a dBASE file with attribute information, and an index file.

The Shapefile to Coverage tool can convert the shapefile spatial and attribute information to an ArcInfo coverage. Shapefiles store only one of the following feature types: line, point, multipoint, or polygon. Polygon features may overlap and can be converted to regions. Lines can optionally be converted as routes and sections. Shapefiles can be generated with the tools in the Import to Shapefile toolset.

Standard Linear Format (SLF) - used to carry several NIMA data products. The ArcInfo SLF translator only converts the primary SLF data product, Interim Terrain Data (ITD) 2D, which is a terrain analysis product produced by NIMA’s Feature Extraction Segment of the Digital Product System (DPS). The coordinate system is longitude and latitude based on the WGS84 ellipsoid. Each SLF file contains a separate layer or category of data, including slope, drainage, transportation, vegetation, materials, and obstacles. Each layer contains a different set of standard attributes. To make use of the attribute information requires the necessary military specifications describing each of the various feature codes and their respective values. The SLF to Coverage tool stores extensive file history and header information in ASCII text files. To maintain the complex SLF data structure in ArcInfo, we are required to store relationships between features in JOIN tables and related files. The SLF to Coverage tool automatically defines and stores the relate environment. The Coverage to SLF tool requires feature attributes and header information to be structured the same as the output from SLF to Coverage.

Topologically Integrated Geographic Encoding and Referencing System (TIGER) - the line network product of the TIGER system available from the U.S. Census Bureau. The cartographic base is taken from GBF/DIME, where available, and from the USGS 1:100,000-scale national map series in all other areas, to have continuous coverage for the entire United States. The extract from the TIGER system is available in ASCII format on both CD-ROM (compact disc read-only memory) and tape media. All released versions of TIGER/Lines files are supported.

Vector Product Format (VPF) - originally developed by ESRI under contract to NIMA as part of the Digital Chart of the World (DCW) effort. VPF has been adopted into an international spatial standard as the Digital Geographic Information Exchange standard. VPF can be considered as a data model rather than a data format. It is designed for direct use rather than as a method of data exchange.

It is layered into five levels. At its lowest level, the database consists of geometric and cartographic primitives. Next is thematic information called features which make up coverages which in turn make up libraries. VPF import and export commands have been developed to convert a VPF database to an ArcInfo database. A single VPF cover or table can be converted. There is also a VPF demo that provides a graphical front end to enable users to visually select and convert entire libraries of data.


Supported image formats

Arc Digitized Raster Graphics (ADRG) - distributed on CD - ROM by the National Imagery and Mapping Agency. This data consists of raster images and other graphics generated by scanning source documents. ADRG data is geographically referenced using the equal arc-second raster chart/map (ARC) system in which the globe is divided into 18 latitudinal bands or zones. Each ADRG CD volume contains a set of data files arranged hierarchically. The raster data is organized by distribution rectangle; with each distribution rectangle there is one physical true color 3 band (RGB) composite image per zone, referred to as a Zone Distribution Rectangle (ZDR). There is also an overview image for the entire distribution rectangle. The IMAGE INTEGRATOR allows the user to display any image on the CD - ROM (either a ZDR or an overview image) by specifying its pathname on the mounted CD. (Reference Military Specification-MIL-A-890007.)

BIL, BIP, and BSQ - an ASCII data description file that describes the layout of the image data, black-and-white, grayscale, pseudocolor and multiband.

BMP - Windows bitmap image format.

DTED (Digital Terrain Elevation Data) - distributed by the NIMA. DTED is designed primarily for data storage and exchange. Each DTED file is arranged in 1 degree by 1 degree geographic areas where elevation matrix intervals vary according to latitude.

ERDAS - the following types of ERDAS images can be displayed:

ERDAS Rev 7.3 .lan and .gis files
ERDAS Rev 7.4 .lan and .gis files

GRASS (Geographical Resource Analysis Support  System) - a public-domain GIS created by the Army Corps of Engineers Construction Engineering Research Laboratory (CERL). GRASS 4.0 format is supported by the IMAGE INTEGRATOR.

Grid - there are two types of grids, integer and floating-point.

Integer grids can be used to represent discrete data (e.g., soil type and land use). The attributes for an integer grid are stored in a value attribute table (VAT).

Floating-point grids are used to represent continuous phenomena. These grids do not have a VAT because the cells in the grid can assume any value within a given range. The cells in this type of grid do not fall neatly into discrete categories. The cell value itself is the attribute at that location. For example, in a grid that represents elevation data in meters above sea level, a cell with a value of 10.1662 indicates that the location is about ten meters above sea level.

IMAGINE - ERDAS’ GIS/image processing product. IMAGINE is a multiband image stored together with metadata pertaining to the file in a single binary file. Direct display and plotting is supported through the IMAGE INTEGRATOR. IMAGINE files can be converted to stacks of grid, with one layer in the stack for each band in the grid using IMAGEGRID and GRIDIMAGE.

JFIF - JPEG File Interchange Format images. This image format uses JPEG compression.

RLC ( run-length compressed) - used for scanned monochrome images. The file is interpreted as a sequence of 16-bit words with each word corresponding to an unsigned short integer. The header is followed by the run-length compressed data for each row in the scanned image. Each row is stored as a sequence of words.

Sun Raster files - suitable for storing monochrome, grayscale, pseudocolor, and true color images. The files have a fixed-length header that is followed by an optional variable-length colormap. Sun Raster files support a byte-level run-encoding scheme. Includes: 1, 8, 24, or 32 bits per pixel.

Tag Image File Format (TIFF) - widely used in the desktop publishing world. It serves as an interface to several scanners and graphic arts packages. TIFF supports black-and-white, grayscale, pseudocolor, and true color images, all of which can be stored in a compressed or uncompressed format.


Converting images

Two ArcToolbox tools support the conversion between images and grids. One of the purposes of converting an image to a grid is to be able to use the GRID Map Algebra for geometric correction and adjustment.

Image to Grid converts black-and-white, grayscale, pseudocolor, and multiband images into grids.

Grid to Image is used to convert a grid into an image. GRIDIMAGE can convert to ERDAS, RLC, Sun Raster files, BIL, BIP or TIFF images.


Converting grids

Grids can also be created from ArcInfo coverages and ASCII files using ArcToolbox tools.

ASCII to Grid creates a grid from an ASCII file containing simple header information followed by a stream of z values. The header information consists of the origin, the number of rows and columns, the mesh point spacing, and optionally, the value used to represent NODATA mesh points. This information is followed by a space-delimited list of the z values. The output can be an integer or floating-point grid.

Point Coverage to Grid creates an integer grid from points in a coverage. Grid cells containing only one of the input points are assigned the value of a specified coverage item. Cells that do not contain any input points are assigned the NODATA value. A weighting table may be provided to resolve cases where a single grid cell includes more than one point.

Line Coverage to Grid creates an integer grid from a line coverage. Grid cells containing only one arc from the input coverage are assigned the value of a specified item. Cells that do not contain any arcs are assigned the NODATA value. A weighting table may be provided to resolve cases where a single grid cell includes more than one arc.

Polygon Coverage to Grid creates an integer grid from a polygon coverage. Grid cells falling within a single polygon are assigned the value of a specified coverage item. Cells that do not contain any polygons are assigned the NODATA value. A weighting table may be provided to resolve cases where a single grid cell includes more than one polygon.

Grids can be also be converted to coverages and ASCII files.

Grid to ASCII converts a grid to a simple ASCII text file. The file consists of header information containing keywords and values, followed by cell values in row-major order. With integer grids, the item in the VAT to be converted is specified on the command line.

Grid to Line Coverage converts an integer grid of linear features to a line coverage. A surface could be suitable for conversion to linear features following edge-enhancement operations.

Grid to Polygon Coverage converts an integer grid to a polygon coverage. Contiguous cells with the same value are grouped together to form polygons. Polygon boundaries are defined by the borders of cells in the grid. Attributes of the grid can be transferred to the coverage using RELATE or JOINITEM.


Converting DTED data

DTED files are designed to be contiguous, with no gaps and overlap only along adjacent boundaries. The terrain elevation information is expressed in meters. The elevation posts are defined by the intersections of rows and columns within a matrix. A DTED data set can be converted to ArcInfo GRID format directly off of CD-ROM using the DTED to Grid tool.

The DTED to Grid tool converts a US NIMA DTED file into a grid. At latitudes exceeding 50 degrees, the DTED data is no longer square cells. These will be resampled using bilinear interpolation to create square grid cells. The column/row (X,Y) orientation of the DTED data is converted to the row/column (X,Y) orientation of the grid data structure. DTED data is published in geographic decimal degrees (latitude and longitude) and the vertical unit of measure is meters.


Grids as lattices

  Lattices and Grids
  From DEMs
  From tins

Lattices and Grids

Lattices and grids are stored using the same data model. The lattice interpretation of the data model considers each mesh point as a surface value at the center of a cell; it does not imply an area of constant value. In contrast, the grid interpretation of the data model considers each cell as a square area with a constant attribute value. All locations within the cell are assumed to have the same value. The data model stores the z values in one of two formats: as integer or floating-point numbers.

There are additional data sources that can create a surface grid lattice. These include Digital Elevation Models (DEMs), ASCII text files, irregularly spaced points in coverages or GENERATE files, and tins.

The following table summarizes the commands that can be used to convert each supported data type to a lattice.

Type of input data	Input format	Conversion tool
	USGS DEMs	DEM to Grid
	ASCII files	ASCII to GRID
Regularly spaced data	Point coverages	Point Coverage to Grid
	Images	Image to Grid
	Tins	Tin to Grid
Irregularly spaced data	Point coverages	Point Coverage to Grid
	Line coverages	Line Coverage to Grid
	Polygon coverages	Polygon Coverage to Grid
From DEMs

The DEM to Grid tool creates a lattice from Digital Elevation Models (DEMs) in the USGS format. Digital terrain data covering most regions of the United States are available in the USGS format from the U.S. Geological Survey. DEMs covering most regions of the world are available in USGS formats from SPOT Image Corporation and STX Corporation.

Format	USGS	SPOT Corp.	STX Corp.
USGS 7.5'	4	4	4
USGS 1¡	4
Digital terrain data in the USGS format is available for two geographic extents: 7.5-minute quadrangles and 1-degree quadrangles. The DEM to Grid tool can convert either of these to a lattice. USGS 7.5-minute DEMs contain surface elevations at a constant mesh-point spacing of 30 meters; the z values are usually expressed in meters. In contrast, 1-degree DEMs contain ground elevations at an interval of 3 arc-seconds; the z values are expressed in meters.

From tins

The Tin to Grid tool interpolates mesh-point z values from a tin at a specified sampling interval to produce the lattice. The mesh-point z values are interpolated from the tin using either LINEAR or QUINTIC interpolation. The output lattice covers a rectangular area Mesh points falling outside the tin’s zone of interpolation are set to the NODATA value.


Converting lattices to other data formats

Possible formats

Lattices can also be converted back to these formats as the following table illustrates:

Output format	Data conversion tool
Tin	Grid to Tin
Line coverage	Grid to Line Coverage
Polygon coverage	Grid to Polygon Coverage
USGS DEM	Grid to DEM
ASCII file	Grid to ASCII
Image	Grid to Image
To tins

Grid to Tin creates a tin containing sufficient lattice mesh points to achieve a specified maximum z value difference between the two surfaces. It is frequently used to convert a lattice created from a DEM to a tin.

To coverages

There are many options for converting a lattice to a coverage. Significant mesh points representing heights of land, depressions, or significant changes in the surface can be extracted and converted to a point coverage.


Creating tins

The Create Tin Wizard is the Toolbox’s primary tool for generating tins. It is a powerful tool for building tins from multiple data sources. Each input feature can also be incorporated into the tin in accordance with the type of surface morphology it represents.

The Add coverage option is used to input point, line, and polygon coverages.

The Add Generate file option is used to input ASCII text files containing xyz coordinates for points, lines, or polygons in the GENERATE input file format. These files differ from standard GENERATE input files in that they also contain a z value for each x,y location. GENERATE input files can be used to input photogrammetric data gathered from stereoplotters.


Define Projection Wizard

Records the coordinate system information of your dataset including any associated projection parameters, datum and spheroid. It creates or modifies the geodataset’s projection definition file (PRJ) that stores the projection parameters. If your dataset is in geographic coordinates, using decimal degrees (DD) and based on the NAD27 datum, you would define the following parameters:

Projection: Geographic
Units: DD
Datum: NAD27 (US-NADCON)

To actually project the dataset or transform the datum or spheroid, you need to use the Project Wizard which requires that your dataset has a PRJ file.

Related Topics


Setting projection parameters

Parameters vary by projection. View details on the parameters specific to your chosen projection to determine the appropriate input.

  Units

  1st and 2nd standard parallels

  Radius of the sphere of reference

  Scale factor

  Scale factor at center of projection

  Longitude of center of projection

  Projection origin

  Latitude of center of projection

  Latitude of origin of projection

  Latitude of standard parallel

  Latitude of true scale

  False easting, False northing

  X and Y Shift

  Azimuth

Examples of parameters for some common projections.

  Universal Transverse Mercator (UTM) coordinate system

  State Plane Coordinate System

  Lambert Conformal projection

  Transverse Mercator projection

  Geographic coordinate system


Units

All projections use linear units of measure; you have two choices:

meters - Refers to International meters.

feet - Refers to US survey feet.

1 International meter = 3937/1200 US survey feet (exact)

To use a linear unit other than meters or feet, enter a conversion factor in the Units entry field. Your chosen unit must be expressed in units per meter. For example, to use km units, enter ‘0.001’, since 1 m = 0.001 km. On the other hand, if you want to use cm units, you would enter ‘100’, since 1 m = 100 cm.

Four angular units—expressing latitude and longitude values—are available for datasets in Geographic coordinates:

DD - Decimal Degrees
        example: 10.5 DD

DM - Decimal Minutes
        example: 630 DM

DS - Decimal Seconds
        example: 37800 DS

Radians
        example: 0.183259571 RADIANS


1st and 2nd standard parallel

There are 3 types of developable surfaces onto which most map projections are mathematically projected. They are the cylinder, cone and plane. Cylinders and cones may touch the spheroid (be tangent) along one parallel referred to as the Standard Parallel. They may also cut the spheroid (be secant) along two parallels. In this case they are referred as the First and Second Standard Parallels. Usually you get true scale and lowest distortion along the Standard Parallels. They are expressed in DMS.

For example, for California State Plane zone 1, which uses the Lambert Conformal Conic projection, the First and Second Standard Parallels are 40 00 00 DMS and 41 40 00 DMS respectively.


Radius of the sphere of reference

Projections are based on a mathematical model of the real world as a sphere or a spheroid. In the case of a sphere, it is completely defined with one parameter, the radius. The default radius of the Sphere of Reference is 6370997 meters; you can enter your custom value in meters.


Scale factor

A value that shows how much the scale has been adjusted along a specific meridian or parallel. For example, for UTM projection, the Scale Factor along the Central Meridian is 0.9996. In other words the scale is reduced along the Central Meridian by a factor of 1:2500. Scale distortion increases as you travel away from the Central Meridian and reaches true scale (1.0000) along two parallel lines about 180 km East and West of the Central Meridian.

Scale Factors are applied to distribute the distortions in scale within the study area. Scale distortions are an inevitable result of trying to fit a curved surface on a flat plane.


Scale factor at center of projection

The Scale Factor at the center of the projection. See also Scale factor.


Longitude of center of projection

The longitude that passes through the Center of the Projection. For UTM Zone 10,  the Center of Projection is (-123,0). The means the Longitude of Center of Projection for this UTM zone is 123 W. Typically for conic projections, a longitude near the center of the study area is chosen as the Central Meridian. For conic projections, the central meridian is the only line of longitude that is truly vertical on the map.


Projection origin:  Central meridian and Latitude of origin

The true origin of a projection is defined by the intersection of the Central meridian or the Longitude of center of projection and the Latitude of origin or the Latitude of center of projection, both expressed in degrees, minutes, seconds (123 0 0).

Usually a longitude near the center of the study area is chosen to be the Central meridian. This makes half of the x-coordinates positive and half of the x-coordinates negative. It is awkward to deal with negative coordinates. To offset these negative x-coordinates, a suitable constant positive value is added to all the x-coordinates after the data has been projected. This common practice is termed ‘adding a False Easting’. False Easting values are always defined in meters irrespective of the units of the dataset.

The Latitude of origin is often chosen to pass below the study area to make all the y-coordinates positive. However for a projection like UTM where the latitude of origin is the Equator, all the y-coordinates come out negative for datasets in the Southern Hemisphere. To offset these negative y-coordinates, a constant positive value is applied to all the y-coordinates after the data has been projected. This practice is termed ‘adding a False Northing’. False Northing values are always defined in meters irrespective of the units of the dataset.


Latitude of center of projection

The parallel of latitude expressed in DMS that passes through the center of the projection. There are 3 types of developable surfaces onto which most map projections are mathematically projected. They are cylinder, cone and plane. In case of a plane touching the spheroid at one point, we automatically arrive at the Center of Projection. The specific latitude that passes through this point of tangency becomes our Latitude of Center of projection. Unlike Latitude of Origin of Projection, you cannot conveniently adjust it to make your y-coordinates positive. You have to apply a False Northing.


Latitude of origin of projection

The Latitude value expressed in DMS that passes through a chosen origin of the projection. For example, in the case of the UTM projection, the latitude of origin is the Equator. In the California State Plane zone 1, which uses Lambert  Conformal Conic projection, the latitude of origin is 39 20 00 DMS. The Latitude of 0rigin can be conveniently chosen to pass below the study area. This automatically makes the y-coordinates positive. You do not need to apply a False Northing.


Latitude of standard parallel

There are 3 types of developable surface onto which most map projections are mathematically projected. They are the cylinder, cone and plane. Cylinders and cones may touch the spheroid (be tangent) along one parallel referred to as the Standard Parallel. They may also cut the spheroid (be secant) along two parallels. In this case they are referred as the First and Second Standard Parallels. Usually you get true scale and lowest distortion along the Standard Parallels. They are expressed in DMS.

For example, for California State Plane zone 1, which uses the Lambert Conformal Conic projection, the First and Second Standard Parallels are 40 00 00 DMS and 41 40 00 DMS respectively.


Latitude of true scale

The latitude along which you get true scale. For example for Eckert IV projection, the scale is true along parallels 40 30 00 DMS North and South.


False easting/False northing

False Easting is a constant value that is added to the x-coordinates of a dataset after it has been projected. False Eastings are often used to remove any negative values in x. False Eastings are always defined in meters irrespective of the units of the dataset.

False Northing is a constant value that is added to the y-coordinates of a dataset after it has been projected. False northings are often used to remove any negative values in y. False Northings are always defined in meters irrespective of the units of the dataset.

It a common practice to apply False Eastings and False Northings to datasets after they have been projected to arrive with a dataset containing only positive coordinates. Computing is easier with positive coordinates. You can also use False Easting and False Northing parameters to remove redundant parts of a coordinate. For example, if you know that a dataset’s Y-coordinates are all greater than five million you could set a False Northing of -5000000.


X-Shift/Y-Shift

X-Shifts and Y-Shifts come into play when you need to work with projections that don’t have built-in False Easting and False Northing parameters.

The False Easting/X-Shift parameters are often used to make sure a dataset doesn’t have any negative x-coordinates or to remove redundant parts of x-coordinates.

The False Northing/Y-Shift parameters are often used to make sure a dataset doesn’t have any negative y-coordinates or to remove redundant parts of y-coordinates.

Unlike the built-in false easting and northing parameters, PROJECT doesn’t undo the X-Shift and Y-Shift parameters correctly. For example, if you see the .prj file of your dataset shows an X-Shift of 500000, you know that a constant value of 500,000 was applied to all the x-coordinates after it was projected. If you want to project this data back to Geographic or some other projection, you must first ‘un-do’ the shift by subtracting 500,000 from all the x-coordinates. You would do this by entering an X-Shift of -500000.

If your .prj file shows a Y-Shift of 10000000, you know that a constant value of 10,000,000 was applied to all the y-coordinates of your dataset after it was projected. To project this dataset to some other projection, you must first normalize the data by subtracting 10,000,000 from all the y-coordinates. You would enter a Y-Shift of -10000000.

Unlike False Eastings/Northings, the values of X-Shifts/Y-Shifts are always entered in the units of your dataset.


Azimuth

Azimuth is an angular direction. A line that runs from the Equator to the North pole has an azimuth of zero. A line running East along the Equator has an azimuth of 90. An angular value expressed in DMS to specify the oblique aspect of a projection such as Oblique Mercator. The orientation is represented by a line that passes through a single point (origin of the projection) and the angle of Azimuth it subtends.


Common projection parameter examples

  Universal Transverse Mercator (UTM) coordinate system

  State Plane Coordinate System

  Lambert Conformal projection

  Transverse Mercator projection

  Geographic coordinate system


Geographic coordinate system

Units: DD
Datum: WGS84


State Plane Coordinate System (SPCS)

Units: feet
Datum: NAD83
FIPS Zone: 401


Universal Transverse Mercator (UTM) coordinate system

Units: meters
Datum: WGS84
Zone: 10


Lambert Conformal projection

Units: feet
Datum: WGS84
1st standard parallel: 40 00 00 DMS
2nd standard parallel: 41 40 00 DMS
Longitude of center of projection: -122 00 00 DMS
Latitude of origin of projection: 39 20 00 DMS
False easting: 2000000 m
False northing: 500000 m


Transverse Mercator projection

Units: meters
Datum: WGS84
Scale factor at center of projection: 0.99996
Longitude of center of projection: -123 00 00 DMS
Latitude of origin of projection: 00 00 00 DMS
False easting: 500000 m
False northing: 0 m


Selecting a datum or spheroid

A Datum is a system of measurement that includes an initial starting point and a specific spheroid. Selecting a Datum automatically selects the appropriate spheroid. For example, if you select NAD 1927 (US-NADCON) as datum for your Geographic dataset, the Clarke 1866 spheroid associated with this datum is automatically recorded in the .prj file.

To change the datum from NAD27 to NAD83, for example, requires that your dataset has a datum defined.

Use this option to change to a different datum.

A Spheroid is a representation of the Earth, characterized by longitudes (parallels) and latitudes (meridians). Selecting a Spheroid does not include a datum; it does, however, automatically set its related Semimajor axis (Equatorial radius) and the Semiminor axis (Polar radius) values.

If your specific spheroid is not included, enter its Semimajor axis and Semiminor axis values in meters and the spheroid field will read Custom spheroid.

This option is limited to changing the projection of your dataset based on the same spheroid.


Define Table

Creates an empty INFO table and defines its items.

Notes

Items are defined using the standard data types.

Table names can have up to 32 characters.

Item names are limited to 16 characters. The name can be any combination of characters, except blanks, equal signs (=), commas and the current delimiter character. However, the first character of an item name cannot be a number (09), hyphen (-), asterisk (*), slash (/), plus sign (+), comma (,), single quotation mark ('), or left or right parenthesis. Item names are not case sensitive and each item name must be unique.

We recommend not to name the table with Arc file extensions, such as AAT, BND, LOG, LUT, NAT, PAT, PRJ, RAT, TAT, TIC, since these files are created and maintained by ArcInfo.

Related Topics


Name the table you want to create. The name can have up to 32 characters.


This is the column number in the Text file, not in the output point attribute table.

Use the arrow buttons to navigate from one item to another.


Inserts the item in the table and increments the Item number counter by 1.


Removes an current Item number from the table.


The type of item to be created:

Integer - integer stored as 1 byte per digit (width from 1 to 16). Maximum value possible is 9,999,999,999,999,998 and the minimum value is -999,999,999,999,999. If the value is negative, one byte of storage is used for the minus sign.

Character- character (width up to 320 alphanumeric characters).

Binary - whole numbers stored as binary integers (width of 2 or 4 bytes only). The maximum value for width of 2 is 32,767 and the minimum value is -32,768. The maximum value for width of 4 is 2,147,483,647 and the minimum is -2,147,483,648.

Floating point - decimal numbers stored in internal floating point representation (width of 4 or 8 bytes only). A 4-byte width is single precision real (approximately 7-9 digits of precision). An 8-byte width is double precision real (approximately 15-17 digits of precision). The maximum value for a 4-byte width is 3.402823466e+38, and the minimum positive value is 1.175494351e-38. The maximum value for an 8-byte width is 1.7976931348623158e+308, and the minimum positive value is 2.225073858507201e-308.

Numeric - decimal numbers stored as 1 byte per digit, including the decimal point and minus sign if the value is negative (width from 1 to 16).

Date - dates in the form of MM/DD/YY or MM/DD/YYYY (item width is fixed at 8 and stored internally as YYYYMMDD).


Item name - The name of the new item.

The name can be any combination of characters, except blanks, equal signs (=), commas and the current delimiter character.  Invalid characters within the name are replaced with an underscore (_).

The first character of an item name cannot be a number (09), hyphen (-), asterisk (*), slash (/), plus sign (+), comma (,), single quotation mark ('), or left or right parenthesis.  Leading numbers or invalid characters are replaced with a capital A.

For example, ‘my 1st item’ becomes ‘MY_1ST_ITEM’; ‘2nd item’ becomes ‘AND_ITEM’.

NOTE: Because item names are not case sensitive, lower case characters are converted to upper case characters.


Item width - the internal storage width, in number of characters or bytes, that the item requires.

NOTE: Numeric items use a byte of storage for the decimal point and for the negative sign if the value is negative. Be sure to make the input width large enough to avoid having problems entering your data.


Display width - The number of spaces used to display the item values.


Decimal places - The number of digits to the right of the decimal place for item types which hold decimal numbers. For Numeric items, the number cannot exceed Item width minus 1. The number zero (0) is valid.


The total number of items that will be defined.


DEM to Grid

Converts a DEM in USGS format to a lattice. A lattice is essentially the same as a grid, providing the same functionality.

Notes

The cell size of the grid created by the DEM to grid tool is the same in both the x and y directions. If the input USGS DEM has a different cell size in the x and y directions, it is resampled during the conversion process. It is resampled using bilinear interpolation at cellsize equal to the smaller of the input DEM’s cell sizes in x or y.

The tool transfers the projection and units information contained in the DEM header record to a map projection file in the Output grid directory.

When a Z-factor other than 1 is given, the Output grid ZUNITS are set to UNKNOWN.

The tool applies the spatial resolution value stored in the DEM. In USGS DEMs, this information is stored in Data Element 14 in Logical Record Type A. The spatial resolution value is used to scale all input USGS DEM elevation values.

Projecting DEMs

Supported file extension

Description of USGS DEMs

Digital terrain data covering most regions in the United States is available in the USGS DEM format from the U. S. Geological Survey.  For more information write the National Cartographic Information Center, 507 National Center, Reston, VA  22092.

It is important to note the differences between lattices created from USGS 7.5-minute and 1-degree DEMs. The following table compares lattices created from these two sources:

Factor                 Grid from a           Grid from a
                       7.5-minute DEM        1-degree DEM
Geographic extent
 in lat long:          7.5'  x 7.5'          1¡ x 1¡
 in km (approx.):      12 km x 14 km         90 km x 110 km

Projection:            UTM                   GEOGRAPHIC
Zone:                  yes                   no
Ground UNITS:          meters              arc-seconds
Surface ZUNITS:        meters              meters
Spheroid:              CLARKE1866          WGS72
Xshift:                0.000000            0.00000
Yshift:                0.000000            0.00000

Distance between       30 m x 30 m         3 arc-seconds
 elevation points                          75 m x 90 m
 in x and y                              (approx. in USA)

Number of elevation    varies,             constant
 points in x and y     approx. 380 x 450   1201 x 1201

Variation in ground    no variation,       varies with
 distance between      spacing is          the latitude
 elevation-point       constant
 spacing across
 the grid

Grids constructed from USGS 1-degree DEMs are not immediately suitable for the volume, slope, or accurate visibility analysis because the x,y locations are measured in latitude and longitude, but the z values are measured in meters. Consequently, the actual distance on the ground represented by one ground UNIT is not constant; and the ground UNITS and the surface ZUNITS are not in the same units of measure.

Unlike USGS 7.5-minute DEMs that contain surface elevations at a constant spacing of 30 meters, 1-degree DEMs contain ground elevations at an interval of 3 arc-seconds. The actual distance in ground units represented by 3 arc-seconds varies with latitude even within the grid. For example, in the vicinity of southern California, at the top of the grid, 3 arc-seconds measure 76.86 meters in x, and 92.36 meters in y. At the bottom of the grid, 3 arc-seconds measure 77.11 meters in x. In the region of the North Pole, the distance in x approaches zero.

The 7.5-minute USGS DEMs are a by-product of the ortho-photomapping program. Some orthophotos were produced using semiautomatic profiling devices that yield elevations along profiles. “When these heights are re-sampled to a 30 meter square grid, the interpolation technique produces estimated elevations which have a much stronger spatial autocorrelation along the direction parallel to the profiles than in the orthogonal direction. Many images produced from these models have clearly visible ‘stripes’ parallel with the scanning direction of the profiler”.  For a reference on this topic see:

Mark, D., “Automated Detection of Drainage Networks from Digital Elevation Models”, Proceedings of the Sixth International Symposium on Computer Assisted Cartography (Auto-Carto VI), Vol. 2, 1983: 288-298.

You can check the data for this effect by applying the ArcInfo GRID HILLSHADE function to the grid. Display the hillshade grid with the ArcInfo IMAGE command in GRID or ARCPLOT. If striping is visible you may want to consider using the ArcInfo GRID FOCALMEAN function to smooth the elevation values.

Related Topics


The DEM you want to convert.


The grid you will create.


Choose the data type for your output grid:

Float – creates a grid with floating point coordinate values. Floating point grids preserve coordinate accuracy at the expense of disk storage space.

Integer – creates a grid with integer coordinate values. If your accuracy requirements permit it, create an integer grid. It uses less disk space and processing tends to be faster.


Select the format of the input DEM.

USGS – uses the standard 7.5-minute, 1-degree, or any other USGS DEM formats.

SPOT – uses SPOT’s Terrain Access Made Easy (TAME) format.


The z-factor states how many ground units in your DEM equal one elevation, or z-unit. It is possible that a DEM’s ground units are in meters and its elevation units are in feet. The z-factor value 1 maintains the DEM’s ground and elevation units in the output lattice. To equalize ground and elevation units, use the z-factor 0.3048 to convert feet to meters, and the z-factor 3.2808 to convert meters to feet.

NOTE: The ground units of a 1-degree USGS DEM are typically in 3 arc-seconds. The actual ground distance for 3 arc-seconds varies with the latitude of the grid, increasing from the poles toward the equator.


Projecting DEMs

To make a surface model suitable for volume, slope and accurate visibility analysis, the ground units in the 1-degree USGS DEM must be projected to a nonangular unit of measure, such as UTM or Lambert. And the surface ZUNITS should be expressed in the same units of measure as the ground UNITS.

Use the Project Wizard with Bilinear or Cubic resampling to convert a grid to the desired projection or to change datums. The following projection parameters are typical for this procedure:

Input projection:

projection geographic

units ds

zunits meters

datum wgs72

Output projection:

projection utm

zone 11

units meters

zunits meters

datum nas_c

The datum WGS72 does not share a common transformation method with NAD27 or NAD83 so an equivalent datum must be used.

Note that the Project Wizard does not perform ZUNITS conversion. Use ArcInfo GRID algebra (e.g. outgrid = ingrid * 0.305) to convert ZUNITS.


DFAD to Coverage

Converts a DFAD transfer file to a set of coverages in a new workspace.

Notes

The output coverages may contain overlapping features. For this reason topology is not automatically built so that features will be more accurately preserved.

Each DFAD file contains a number of manuscripts. Each manuscript is converted to a separate coverage in the Output workspace.

The coverages will be named using a common prefix. The coverages will be named DS<nnnn>, where nnnn is the order that the manuscript appeared in the file.

A node attribute table (NAT) is built to flag the exit nodes. DFAD files carry an identifier in the coordinate list for digitized points that exit the manuscript. These points are tagged with a negative latitude representing magnitude, and are stored in DSnnn.NAT.

The output coverage’s ACODE and PCODE INFO files are related through the FACODE field to the output coverage’s Cover-ID field in the arc attribute table. The output coverage’s XCODE INFO file is related through the FACODE field to the Cover-ID field in the polygon attribute table.

In addition to the standard feature attribute tables, each coverage will contain the following INFO files.

Supported file extension

Related Topics


The DFAD file you want to convert to a set of coverages.


The workspace you will create to store the set of coverages.


INFO files

DATAFILE NAME: DSnnn.ACODE
COL ITEM NAME         WDTH OPUT TYP N.DEC
 1  FACODE              4    5  B    -
 5  HEIGHT              4    5  B    -
 9  FICODE              4    5  B    -
13  SMCCODE             4    5  B    -
17  DIRECT              1    1  N    -
18  WIDTH               2    3  B    -

DATAFILE NAME: DSnnn.PCODE
COL ITEM NAME         WDTH OPUT TYP N.DEC
 1  FACODE              4    5  B    -
 5  HEIGHT              4    5  B    -
 9  FICODE              4    5  B    -
13  SMCCODE             4    5  B    -
17  NSTRUCT_PSK         2    2  N    -
19  PCT_TREE_COV        2    2  N    -
21  PCT_ROOF_COV        2    2  N    -

DATAFILE NAME: DSnnn.XCODE
COL ITEM NAME         WDTH OPUT TYP N.DEC
 1  FACODE              4    5  B    -
 5  HEIGHT              4    5  B    -
 9  FICODE              4    5  B    -
13  SMCCODE             4    5  B    -
17  ORIENTATION         2    3  B    -
19  LENGTH              2    3  B    -
21  WIDTH               2    3  B    -

DATAFILE NAME: DSnnn.DES
COL ITEM NAME         WDTH OPUT TYP N.DEC
1   IDENTIFIER         20   20  C    -
21  VALUE              30   30  C    -

The relate environment used to link features and attribute tables is saved in an INFO relate table for each coverage. The relate environment can be restored.

DATAFILE NAME: DSnnn.RELATE
COL ITEM NAME         WDTH OPUT TYP N.DEC
 1  RELATION            8    8  C    -
 9  TABLE-ID          128  128  C    -
137 DATABASE            8    8  C    -
145 ITEM               16   16  C    -
161 COLUMN             32   32  C    -
193 TYPE               16   16  C    -
209 ACCESS              4    4  C    -


DIME to Coverage

Converts a DIME file to a line coverage and an ACODE attribute table containing DIME field attributes. The Output coverage is similar to a newly digitized coverage with a set of feature attributes in a related INFO table.

Steps for converting GBF/DIME files

Notes

Coverage lines can be related to their ACODE attributes by the <cover>-ID item.

Since other tools may alter internal node numbers (FNODE# and TNODE#), consider maintaining the DIME from-nodes and to-nodes (F-NODE and T-NODE ) as separate AAT attributes.

Supported file extension

Related Topics


Steps for converting GBF/DIME files

Follow these steps to create an ArcInfo coverage with line and polygon topology.

1	Use the DIME to Coverage tool to create a coverage.

All of the records in the DIME file may not be converted into lines. Any records that have missing coordinates cannot be converted, and records that have an NS-CODE of ‘9’ will be added to the ACODE table as alternative addresses.

2	If Geographic coordinates were converted, use the Project Wizard to convert the latitude and longitude coordinates to a suitable planar coordinate system. An example would be projecting  a coverage from decimal degrees to UTM meters in Zone 15. This step is not necessary if the State Plane option was specified to use the State Plane coordinates.

3	Edit the coverage to remove invalid long arcs connected to only one useful node.

Extraneous arcs are easier to select and delete before running the Clean tool.

4	Create topology.

If any new arcs are created as a result of the Clean tool, they must be assigned a unique User-ID and the attributes corrected before running ArcInfo commands such as ADDRESSCREATE and TURNTABLE.

If only line features are needed, use the Clean tool with the Feature class set to Line to identify intersections as well as build an AAT. Alternatively, to build both polygons and arcs, begin by using the Clean tool with the Feature class set to Poly.

Now create label points for each polygon and update the PAT with the new label points using the Create Polygon Labels tool. After building the polygon coverage, create arc topology using the Build tool with the Feature class set to Line.

Note: Remember that each time a new coverage is created, the ACODE table is also copied. You can delete the previous version of the coverage or change the name of the ACODE table so it will not be copied each time

5	Add attributes to the AAT from the ACODE table (optional).

If you want to add attributes from the ACODE table to the coverage AAT, you can use the Join Tables tool using the coverage User-ID as the Relate item. The ACODE table may contain more records than the AAT because GBF/DIME files contain records with duplicate coordinates and different addresses. These are usually identified by a value of ‘9’ in the NS.CODE item in the ACODE table. The DIME to Coverage tool writes an ACODE record for these GBF/DIME records, but not an arc feature.


The DIME file you want to convert.


The new coverage you will create.


Choose which coordinate system you want to use to create coverage arcs.

Geographic – creates latitude-longitude coordinates (in decimal degrees).

State Plane – creates State Plane coordinates (in feet).


For the 1980 census, the U.S. Census Bureau created Geographic Base Files (GBF) or Dual Independent Map Encoding files (DIME) which were ASCII files containing geographic coordinates of line segments and census area codes for metropolitan areas. All of the DIME files are now being replaced by TIGER/Line for the 1990 census. The TIGER/Line files include both the 1980 and the 1990 census area codes so that databases can be used with 1980 census data as well as 1990 data.


ACODE table

An attribute table named <Output coverage>.ACODE is created which contains all of the fields in a standard DIME file plus the line User-ID. Thus, each DIME record can be related to a line via the User-ID. These are the items contained in the ACODE table:

57 ITEMS: STARTING IN POSITION    1

COL  ITEM NAME         WDTH OPUT TYP N.DEC
1    Output coverage-ID  4    6  B    -
5    PRE.DIR             2    2  C    -
7    STREET.NAME        20   20  C    -
27   STREET.TYPE         4    4  C    -
31   SUF.DIR             2    2  C    -
33   NS.CODE             1    1  C    -
34   L-ED                6    6  C    -
40   R-ED                6    6  C    -
46   FILLER1             4    4  C    -
50   F-MAP.BASIC         3    3  I    -
53   F-MAP.SUF           2    2  C    -
55   T-MAP.BASIC         3    3  I    -
58   T-MAP.SUF           2    2  C    -
60   CODING.LIMIT        1    1  C    -
61   L-F-ADD             6    6  I    -
67   L-T-ADD             6    6  I    -
73   R-F-ADD             6    6  I    -
79   R-T-ADD             6    6  I    -
85   FILE.CODE           4    4  I    -
89   CENSUS.ID           6    6  I    -
95   CHECK.DIGIT         1    1  I    -
96   L-TRACT.BASIC       4    4  I    -
100  L-TRACT.SUF         2    2  I    -
102  R-TRACT.BASIC       4    4  I    -
106  R-TRACT.SUF         2    2  I    -
108  L-ZIP               5    5  I    -
113  R-ZIP               5    5  I    -
118  SMSA                4    4  I    -
122  FILLER2             5    5  C    -
127  F-NODE              4    4  I    -
131  T-NODE              4    4  I    -
135  L-PLACE             4    4  I    -
139  R-PLACE             4    4  I    -
143  L-STATE             2    2  I    -
145  L-COUNTY            3    3  I    -
148  L-MCD               3    3  I    -
151  FILLER3             5    5  C    -
156  L-BLOCK             3    3  I    -
159  FILLER4             3    3  C    -
162  R-STATE             2    2  I    -
164  R-COUNTY            3    3  I    -
167  R-MCD               3    3  I    -
170  FILLER5             5    5  C    -
175  R-BLOCK             3    3  I    -
178  FILLER6             3    3  C    -
181  F-SP.ZONE           2    2  C    -
183  T-SP.ZONE           2    2  C    -
185  FILLER7            24   24  C    -
209  F-LATITUDE          6    6  I    -
215  F-LONGITUDE         7    7  I    -
222  T-LATITUDE          6    6  I    -
228  T-LONGITUDE         7    7  I    -
235  F-SPY               7    7  I    -
242  F-SPX               7    7  I    -
249  T-SPY               7    7  I    -
256  T-SPX               7    7  I    -
263  FILLER8            42   42  C    -

**  REDEFINED ITEMS  **
96   L-TRACT             6    6  C    -
102  R-TRACT             6    6  C    -
50   F-MAP               5    5  C    -
55   T-MAP               5    5  C    -


Dissolve

Simplifies a coverage by merging adjacent polygons, lines or regions which have the same value for a specified item. The tool determines the feature classes in the Input coverage and lists those available for dissolving.

  Poly

  Line

  Poly & Line (Net)

  Region subclass

The Dissolve item determines which values are compared for simplifying and which attributes are transferred to the Output coverage. Choose All items to use all items past the <cover>-ID as a single Dissolve item. All attributes are copied to the Output coverage, but User-IDs are altered. If there are no items past the <cover>-ID, the <cover>-ID is used as the Dissolve item. This option is useful after an Append to dissolve map sheet boundaries. Or choose a single item name if you want to merge adjacent features with the same value for that item. Only the Dissolve item is maintained in the Output coverage.

Notes

You can use a redefined item as the Dissolve item, provided that its begin column is the begin column of a normal item, and its end column is the end column of a normal item. The redefined item may span several normal items. It is transferred to the Output coverage as a regular item.

Route systems are copied to the Output coverage. All section subclasses are maintained.

The node attribute table (NAT) will be maintained for any nodes whose arcs were dissolved.

Processing planar graphs

Recommended post-processing

Update the internal node numbers with the Renumber Nodes tool to ensure uniquely and sequentially numbered nodes.

Related Topics


Dissolve polygons

Polygon topology is created in the Output coverage.

An existing AAT will not be maintained in the Output coverage.

Only one label point is preserved for merged polygons.

All dangling arcs are removed.

Pseudo nodes are removed (unless they are the only node in a polygon, e.g., an island or donut).

If a pseudo node has attributes that are not zero or blank, arcs will not be joined for polygon features.

Region subclasses are maintained, but regions may change shape when polygons or arcs are dissolved.

If all polygons attributes are coded with the same value, then Dissolve with Poly using the All items option will leave you with a null set. If you wish to retain the bounding or outer polygon, then be sure to code the universe polygon with a different value than the rest of the set.

Example

The following coverage is dissolved with Poly on an item called CLASS.


Dissolve lines

Nodes between adjacent arcs containing equal values for the dissolve item are eliminated.

The new <cover>-ID of the merged arc will be the lowest <cover-ID> of the combined arcs.

If a set of merged arcs contains over 500 vertices, a pseudo node is added and a new arc is begun.

An existing PAT will not be maintained in the Output coverage.

Route-system sections residing on merged arcs will have their F-POS and T-POS adjusted so that they occupy the original locations.


Dissolve polygons and lines with Net

Arcs are joined if all item values for one arc are identical for all item values of the other arc on an item-by-item basis.

Both a PAT and AAT, and polygon topology, are created in the Output coverage.

The output AAT has the same items as the Input coverage; only the records for the dissolved arcs will be removed.

Only one label point is preserved for merged polygons.

Dangling arcs and pseudo nodes are not removed.

Arcs are joined as units and before two arcs are joined, the total number of vertices is compared against the 500 vertex limit. If greater than 500, the join is not done.

Route-system sections attached to a deleted arc are removed and ARCLINK# is renumbered.

Region subclasses are maintained, but regions may change shape when polygons or arcs are dissolved.


Dissolve region subclasses

Region topology is created in the Output coverage.

All Input coverage attributes are maintained in the Output coverage.

Example

The figure below shows polygons P and Q that have single associated regions R and S. Merging polygons P and Q yields an empty region intersection set. Since Dissolve takes the intersection and not the union, the region subclass after the Dissolve contains a hole.


The coverage whose polygons, lines or regions you want to dissolve.


Choose the feature class you want to dissolve.

Poly – dissolves polygons

Line – dissolves arcs

Poly & Line (Net) – dissolves polygons and creates a PAT and an AAT for the Output coverage.

Region.<subclass> – dissolves region subclasses and maintains all attributes in the Output coverage.


The tool eliminates nodes or arcs between adjacent lines or polygons containing equal values for the Dissolve item. Choose the Dissolve item.

All items – features with the same values for all items after the <cover>-ID will be merged and all attributes will be copied to the Output coverage.

If there are no items past the <cover>-ID, the <cover>-ID is used as the Dissolve item.

Single Dissolve item – features with the same value for that item will be merged. Only this item will be maintained in the Output coverage.


The coverage you will create.


Dissolve Regions

Creates a new region subclass by merging polygons or regions that have the same value for a specified item. The output regions contain both topology and attributes. The tool determines the feature classes in the Input coverage and lists those available for dissolving.

Poly – merges both adjacent and discontiguous polygons. To view an example click [image].

Region.<subclass> – merges regions from the specified subclass. To view an example click [image].

The Dissolve item determines which attributes are transferred to the Output subclass. Items available for use as Dissolve item with the Poly option are in the polygon attribute table (PAT). Items available for use with the Region.<subclass> option are in the region subclass polygon attribute table (PATregion).

All items – merges features with the same value for all items. All attributes are maintained in the Output subclass. The tool uses the <cover>-ID as Dissolve item if there are no items after the <cover>-ID.

Single item name– merges features with the same value for that item. Only this item is maintained in the Output subclass.

Notes

You can use a redefined item as the Dissolve item, provided that its begin column is the begin column of a normal item, and its end column is the end column of a normal item. The redefined item may span several normal items. It is transferred to the Output coverage as a regular item.

The Poly option is similar to the Dissolve tool with the Poly option, except that Dissolve creates a coverage and Dissolve Regions creates a region subclass.

The Region.<subclass> option is similar to the Dissolve tool with the Region.<subclass> option, but Dissolve cannot create a new subclass.

To maintain the Input coverage, name the Output coverage differently.

All feature classes of the Input coverage are copied to the Output coverage when Output coverage is a new coverage.

To dissolve multiple region subclasses and polygons use the Query Regions tool, which simultaneously merges polygons and multiple region subclasses into a new subclass, based on multiple Dissolve items.

Related Topics


Example for dissolving a region subclass

This example uses Dissolve Regions to merge a single region subclass in a new coverage.

The coverage BOXES has a region subclass RED with regions R1, R2, R3 and R4. Regions R1 and R2 are identical overlapping squares. The subclass PAT has an item TEST with the same value for each region. Using TEST as the Dissolve item creates one output region.

NOTE: Regions are merged horizontally and vertically.


Example for dissolving polygons

The polygons in coverage 'vegcov' are merged using ATTR1 as the Dissolve item to create the region subclass LANDUSE. There is a many-to-one mapping of polygons and their attributes to a region subclass.

VEGCOV.PAT:

Rec    AREA   PERIMETER VEGCOV# VEGCOV-ID  ATTR1  ATTR2
  1  -50.387   28.683      1        0                 0
  2   11.958   16.856      2        1      FOREST   100
  3   13.882   15.116      3        2      FOREST   200
  4   21.489   26.812      4        3      SCRUB    100
  5    1.541    5.182      5        4      FOREST   200
  6    1.517    5.161      6        5      WATER    999

VEGCOV.PATLANDUSE:

Rec    AREA   PERIMETER LANDUSE# LANDUSE-ID  ATTR1
  1   27.381   30.015       1         0      FOREST
  2   21.489   26.812       2         1      SCRUB
  3    1.517    5.161       3         2      WATER


The coverage whose polygons or regions you want to dissolve.


Choose the Feature class you want to merge.

Poly – dissolves polygons to create the Output subclass.

Region.<subclass> – dissolves regions of the selected subclass to create the Output subclass.


The coverage you will create. It cannot already exist unless it is the same as the Input coverage.

The tool automatically displays the Input coverage name. If you don't change the name, the new Output subclass is created there, provided that a region subclass with that name does not already exist.


The region subclass you will create. If Output coverage is the same as Input coverage, the subclass name cannot already exist.


Choose how to merge features:

All items – features with the same values for all items after the <cover>-ID will be merged and all attributes will be maintained in the Output subclass.

The tool uses the <cover>-ID as Dissolve item if there are no items after the <cover>-ID.

Single Dissolve item – features with the same value for that item will be merged. Only this item will be maintained in the Output subclass.


DLG to Coverage Wizard

Converts a Digital Line Graph (DLG) file in either Standard or Optional format into ArcInfo coverages.

Notes

Topology data contained in the DLG file is ignored. You may choose to use the Build tool after executing the wizard, creating topology on the newly created coverage. Sometimes the coverage will have arc intersections and will need to be cleaned using the Clean tool.

The coordinate precision of the output coverage is determined by the current creation rule as outlined by the precision settings in the ArcToolbox options dialog. If the precision setting has not yet been established during the current ArcInfo session, then the creation rule will be Single. This means the DLG to Coverage Wizard will create an output coverage in single precision. (Coordinate values in DLG files have a format definition of F12.2.)

The Output coverage may require editing before polygons or lines can be built and feature attribute tables can be created. For example, checks should be made on the Output coverage to ensure that label points occur within their polygons, arcs match at nodes, polygons close, arcs do not cross, and so on.

Supported file extension

Related Topics


Digital Line Graphs (DLG) are geographic data files provided by the Earth Science Information Center (ESIC, formerly NCIC) of the U.S. Geological Survey. These data files include information from the USGS planimetric map base categories such as transportation, hydrography, contours, and public land survey boundaries. The DLG format is often used to transport data between ArcInfo and other mapping systems.


Categories

The name of a specific DLG category to be converted from the DLG file. Only the selected category will be converted. Otherwise, only the first category in the DLG will be written to the output coverages. A DLG category is equivalent to a layer. Usually, only one category is included in a DLG file. However, some DLGs contain more than one category. Categories are listed in DLG Header records. Selecting categories enables you to create a set of coverages from a number of layers or categories contained in the DLG.


Area records

When the Import all Area records option is chosen, all area records in the DLG file are converted to label points in the Output coverage and the major and minor codes for these Area (A) records are written to the Output coverage PCODE table.

Usually the label point for the first Area record is in the outside polygon, (universe polygon in a coverage). The Skip the first Area Record checkbox allows you to ignore this label since it does not contain attributes. When this option is chosen, labels for all other Area records and the corresponding major/minor codes, are written to the Output coverage PCODE table.

The Import only those Area records with attributes option allows you to convert the label location for those Area records that carry major/minor codes. For some DLG categories, only Area records with attributes have valid label locations, so importing area records without attribute records is not desired. The first Area (A) record is not included in this option.


DLG attributes

Code files for a particular feature class are only created if feature attributes are found in the DLG. The ACODE table holds line attributes; the PCODE table holds line polygon attributes.

The items for each Code file created in INFO by the DLG to Coverage Wizard consist of the following:

COL ITEM NAME        WDTH OPUT TYP N.DEC
 1  cover-ID            4    6  B    -
 5  MAJOR1              6    6  I    -
 9  MINOR1              6    6  I    -
13  MAJOR2              6    6  I    -
17  MINOR2              6    6  I    -
 .    .                 .    .  .    .
 .    .                 .    .  .    .
 .    .                 .    .  .    .
 .  MAJORn              6    6  I    -
 .  MINORn              6    6  I    -

Cover-ID is each feature’s unique identifier. MAJOR1 is the first major feature code in the DLG; MINOR1 is the first minor code. There are as many major/minor pairs in the table as the maximum number of pairs for that feature class in the DLG. If no value appears for a particular code, it will be set to -99999 in the INFO data file to signify ‘No data’.

Attribute codes are organized as major and minor pairs. Code pairs are encoded in two integer fields each containing six digits (i.e., FORTRAN 2I6 format). Each major code represents the category or class to which a DLG feature belongs (e.g., road, stream, or other line class), while minor codes describe each feature more specifically. Thus, a feature class can have multiple pairs of attribute codes.

Feature numbers in the DLG Area (A) records become label point User-IDs for polygons; feature numbers in Line (L) records become User-IDs for arcs in the Output coverage. The same User-IDs are written to the Output coverage ACODE and PCODE tables.

The DLG feature numbers for Node (N) records become User-IDs for nodes in the Output coverage. There is no corresponding Code table for node attributes. The User-IDs and attribute codes for Node (N) records are stored directly in the Output coverage node attribute table (NAT).

For the Output point coverage, the DLG feature numbers in degenerate (zero-length) Line (L) records become User-IDs for points in the point coverage. An associated XCODE table is created to hold degenerate Line (L) attribute codes.


Converting degenerate lines as points

In a DLG, points are stored as zero-length arcs, called degenerate lines. You can choose to convert any degenerate lines to points by specifying an Output point coverage. An INFO table with the extension XCODE will be created for the new Output point coverage. It contains all major and minor code pair values for degenerate Line (L) records. No coverage will be created from degenerate line records unless an output point coverage is specified.

You have the option of joining the XCODE attribute table to the new point coverage’s arc attribute table (AAT) automatically. This makes it easier to access these attributes but makes your AAT larger. If you do not join these two tables, define a relate and use that to access the XCODE table’s attributes.


DLG coordinates and adding a shift

When writing a single precision coverage to a DLG file, you may then apply a positive shift in order to preserve your original coordinate accuracy. For example, a single precision coverage in UTM typically has a negative Y shift of 5,000,000 so the y-coordinates can be utilized correctly as the precision of the coverage will not allow such large values.

The DLG to coverage Wizard writes the projection parameters stored in the DLG file to a projection definition file (PRJ) stored in the Output coverage subdirectory. Values specified for X shift and Y shift are used to create xshift and yshift records in the PRJ. The xshift and yshift parameters will be used in other tools that can read the PRJ file, such as the Coverage to DLG tool and the Project Wizard.

This example shows the parameters stored in a PRJ file.

PROJECTION UTM
UNITS METERS
ZONE 16
YSHIFT 3000000
PARAMETERS

Control Point Information


Control Point Information

DLG header records may also contain parameters of a transformation which are used to convert the internal file coordinates to the ground coordinate system. The DLG to Coverage Wizard will automatically apply any transformation parameters found in the header records to the feature coordinates and control points (in addition to any specified shift).

The header records in the DLG file provide information used to determine the tic locations of the output coverages.

If the fields used to store control point information are blank, the DLG to Coverage Wizard will generate tics for the output coverages.

DLG files usually provide four control points representing the four corners of the map area in the same map coordinate system used to store geographic features. Any transformation or x,y shift applied to the feature coordinates will apply to the control points as well.


Output coverage and attributes

The Output coverage is created from the DLG data. If the Input DLG file contains data produced by the USGS, the Output coverage will usually contain line, polygon and node features created from nondegenerate Line (L) records, Area (A) records and Node (N) records. A node attribute table (NAT) is created for node features. An INFO table with an ACODE extension is created to contain the major/minor pair values for all Line (L) records. Similarly, an INFO table with a PCODE extension will contain Area (A) records.

You have the option to build the output coverage for polygon and/or line topology and join these associated attribute tables to the newly created PAT and AAT files. This is done to make it easier to access these DLG attributes as opposed to relating the files to the corresponding feature attribute tables.

DLG attributes


DLG file properties

DLG Type - There are two DLG formats: DLG Standard and DLG Optional format. These are documented in the DLG Data Users Guides available from any of the USGS Earth Science Information Centers. You should acquire all DLG documents if you plan to use DLG data or DLG formats to transfer ArcInfo data.

Map Name - A descriptive name of the contents. Up to 40 characters in length.

Scale - The map scale. The default value is 0.

Date - Source date, revision date and revision code. Dates entered as YYYY. Code is: P - photo revision, I - photo inspection, D - digital revision. The default is today’s date and no revision code.

Category - The name of the data category or layer. The name can be up to 20 alphanumeric characters in length.

Number of Areas - The number of Area records in the DLG file.

Number of Lines - The number of Line records in the DLG file.

Number of Nodes - The number of Node records in the DLG file.


DTED to Grid

Converts a United States National Imagery and Mapping Agency Digital Terrain Elevation Data (DTED) file into a grid.

Notes

At latitudes exceeding 50 degrees, the DTED data is no longer contained in square cells. These cells will be resampled, using linear interpolation, to create square grid cells.

The column/row (Y,X) orientation of the DTED data is converted to the row/column (X,Y) orientation of the grid data structure.

DTED data is published in geographic decimal seconds (latitude and longitude), and the vertical unit of measure is meters. DTED files are designed to be contiguous, with no gaps and overlap only along adjacent boundaries.

There is a subdirectory for each degree of longitude. The subdirectory name format is <E/W>DDD, where DDD is the degree of longitude. Within this subdirectory are data files for each degree of latitude named <N/S>DD.DT1, where DD is the degree of latitude.

Data can be converted directly from a CD without first copying the data to a disk.

The horizontal units of converted DTED data are decimal seconds, and the vertical units are meters. Therefore newly converted DTED data is of limited use in its raw form and should be projected to a planar coordinate system.

All DTED data is on the WGS84 datum. Using the three parameter datum transformation method available in the Project Wizard, this data can be transformed to other datums. Note that transformation of WGS84 data to any North American datums also requires use of this method.

The Create header file option allows the user to create a metadata header file during the conversion. This header file contains information outlined in the MIL-PRF-89020 section 3.12 through 3.13.

Refer to Military specification MIL-PRF-89020A for further information.

Related Topics


The DTED file you want to convert to a grid.

NOTE: You must specify the full pathname to the file.


The grid you will create.


Create optional metadata header file. This file can be used when converting the grid back to a DTED file. This option will only work when processing the job on a remote Geoprocessing Server, as it uses the DTEDGRID ArcInfo Workstation command, which offers this capability. The ArcObjects method is used when the job is run locally. It does not support header file creation.


dted data      +              +              +              +

               10             20             40             10

grid data      +      +       +       +      +       +      +

               10     15      20      30     40      25     10


Directory of E:\dted

e072   e077   e082   e086   e090   e094   e098   e102   e106   e110
e073   e078   e083   e087   e091   e095   e099   e103   e107   e111
e074   e079   e084   e088   e092   e096   e100   e104   e108   e112
e075   e080   e085   e089   e093   e097   e101   e105   e109   e113
e076   e081

  Directory of E:\dted\e087

n66.dt1   n68.dt1   n70.dt1   n72.dt1   n74.dt1   n67.dt1   n69.dt1   n71.dt1   n73.dt1   n75.dt1


DXF to Coverage Wizard

Converts an AutoCAD Drawing Exchange File (DXF) to a double precision coverage.

DXF files contain drawing elements referred to entities, inserted by a single AutoCAD command. When converted to a coverage, each entity becomes a single feature.

Supported DXF entities

Notes

DXF files in both ASCII and binary formats are supported. The format is automatically detected.

The ASCII format is the standard interchange format used by most CAD systems.

The binary format is structured exactly the same as the ASCII format, but is stored in double precision and executes much faster. Only AutoCAD Releases 10 and 11 binary files are supported

The output TIC and BND files identify the minimum and maximum coordinates of the coverage features.

Supported file extension

Related Topics


DXF Entity types	Convert to

POINT, SHAPE	Points
LINE , 3DLINE	Two-point arcs
RACE , SOLID , 3DFACE	Four- or five-point arcs
TEXT, ATTRIBUTE	Annotation or points
INSERT	Points
CIRCLE , ARC	Up to 361 point arcs
POLYLINE	Multipoint arcs
POLYLINE with bulge	Up to 360 point arcs
BLOCK	Points, two-, four-, five-point
and multipoint arcs
LWPOLYLINE	R13 multipoint arcs


DXF Blocks

Up to 999 layers and 999 unique blocks can be converted.

The Explode Blocks option can convert blocks containing up to 8 levels of nested blocks.

DXF entities convert to these coverage features

Notes

Arcs longer than 500 points are split with the same User-ID.

Circle and Arc entities are stored in DXF files by feature definition as curves through a set of points. In the new coverage, the distance between arc vertices is determined by placing one vertex at each arc degree around the circle or curve. For example, a circle will have 361 vertices: one for each degree around the circle and one last vertex (which equals the first vertex) to close the circle.

Curves converted from Blocks will have 73 vertices: one vertex for every five degrees and one last vertex to close the circle.

Only one elevation value per entity is converted (i.e., the DXF Group code 38 or the first z value for group code 30). Additional individual z values are ignored.

If the Explode Blocks option is selected, one or more options (ie Arcs, Points, Text to Points…) must be checked for the block features to be included in the conversion to coverage.


ACODE and XCODE items

Arc attributes

The coverage ACODE file will contain the following items:

ITEM NAME       WDTH  OPUT  TYP   N.DEC
<cover>-ID        4     5     B
DXF-LAYER        31    31     C      -
DXF-COLOR         3     3     I      -
DXF-THICKNESS     4    12     F      3
DXF-TYPE         10    10     C      -
DXF-ELEVATION     4    12     F      3
DXF-HANDLE       16    16     C      -
DXF-CURVE         1     1     I      -

DXF-LAYER - the layer to which the entity belongs. Although layer names can be longer than 16 characters, they must be unique within the first 16 characters because the DXF-LAYER item definition is only 16 characters wide. The default is 0.

DXF-COLOR - the color (DXF Group code 62) of the entity. If there is no specific color for an entity, it is assigned the default line color found in the DXF layer table in the header of the DXF file. If there is no layer table and no Group code 62 for the entity, DXF-COLOR will be 0. A negative color value means the layer was turned off.

DXF-THICKNESS - the thickness of the entity (DXF Group code 39). The default is 0.

DXF-TYPE - the line type (CONTINUOUS, DASHED, etc.) for DXF Group code 6. If there is no specific line type for the entity, it is assigned the default line type found in the DXF layer table in the header of the DXF file. If there is no layer table, DXF-TYPE will be blank.

DXF-ELEVATION - one elevation value for the entire entity. This value is taken from either group code 38 or the initial z value from group code 30. Group code 38 exists only in AutoCAD DXF files prior to Release 11. Elevation is a single value for the entire entity. Additional Z values representing (X,Y,Z) coordinates for multiple points along a single entity are not converted.

DXF-HANDLE - the DXF entity handle from group code 5. Entity handles are maintained internally in AutoCad and while we preserve the hex value of the original DXF element, it may be overwritten by AutoCad if you convert back to a DXF. It is similar in function as ArcInfo's <cover>#.

DXF-CURVE - indicates whether this line is a curve (Circle or Arc) or a regular line (TRACE, POLYLINE, LWPOLYLINE, 3DFACE or LINE). Set to 1 for a curve and 0 for a non-curve, it is mainly used with ARCDXF to regenerate curves.

Point attributes

The coverage XCODE file will contain the following items:

ITEM NAME       WDTH  OPUT  TYP   N.DEC
<cover>-ID        4     5     B
DXF-LAYER        31    31     C      -
DXF-COLOR         3     3     I      -
DXF-THICKNESS     4    12     F      3
DXF-TYPE         10    10     C      -
DXF-ELEVATION     4    12     F      3
DXF-HANDLE       16    16     C      -
DXF-ANGLE         4    12     F      3
DXF-SIZE          4    12     F      3
DXF-TEXT         xx    xx     C      -

Except for the items listed below, the items in the XCODE file are the same as those in the ACODE file.

DXF-ANGLE - rotation angle in degrees (DXF Group code 50).

DXF-TYPE - the line type for the point feature.

Text attributes

If Text entities are converted with the Text to Points option, the XCODE file will contain these additional items:

ITEM NAME       WDTH  OPUT  TYP   N.DEC
DXF-ANGLE         4    12     F      3
DXF-SIZE          4    12     F      3
DXF-TEXT         xx    xx     C      -

DXF-ANGLE - the angle of the text.

DXF-SIZE - the size of the text.

DXF-TEXT - the text value for the DXF-ATTRIB. If the entity is a Point, Shape or Insert, this field will be blank.

Attribute definitions

If Attributes and Attribute definitions are converted with the Attributes to Points option, the XCODE file will contain these additional items:

ITEM NAME      WDTH  OPUT  TYP   N.DEC
DXF-ATTRIB      xx    xx     C      -
DXF-IID          4     5     B      -

DXF-ATTRIB - holds the BLOCK name for INSERT points, the shape name for SHAPE entities and the tag or item name for ATTRIBs and ATTDEFs. DXF-TEXT will store the item value for ATTRIB and ATTDEF entities. DXF-ATTRIB will be blank for text and point entities.

DXF-IID - used to link ATTRIBUTES to the corresponding INSERT entity. Each INSERT entity can have multiple ATTRIBUTE entities. INSERT entities are converted to point features with a unique User-ID. This User-ID is stored in DXF-IID item of all the ATTRIBUTES entities associated with that INSERT.


The name of the DXF file to be converted. This file must be in AutoCAD’s DXF ASCII or binary format.


Layers

Lists all available layers in the DXF file. A layer is a grouping of a portion of the entities of a drawing. Multiple layers can be defined for one drawing. The characteristics of a layer are globally applied to all entities of that layer. When converted, any combination of layers, and entities within each layer, can be specified for inclusion in a single coverage. Check those layers you want to convert.


The layer you selected to convert, its entity types and a set of conversion options.


The number of arcs created with the Arcs option.

The following DXF entity types can be converted to arcs:

Line
3Dline
Trace
Solid
3Dface
Circle
Arc
Polyline
LW Polyline


The number of points created with the Points option.

The following DXF entity types can be converted to points:

Point
Shape


The number of text entities in the selected layer.


The number of attribute entities in the selected layer.


The number of attribute definition entities in the selected layer.


The number of insert entities in the selected layer.


The entities supported in ArcInfo:

DXF Entity types	Convert to

POINT, SHAPE	Points
LINE , 3DLINE	Two-point arcs
RACE , SOLID , 3DFACE	Four- or five-point arcs
TEXT, ATTRIBUTE	Annotation or points
INSERT	Points
CIRCLE , ARC	Up to 361 point arcs
POLYLINE	Multipoint arcs
POLYLINE with bulge	Up to 360 point arcs
BLOCK	Points, two-, four-, five-point
and multipoint arcs
LWPOLYLINE	R13 multipoint arcs


Converts point entities to points.

The following DXF entity types can be converted to points:

Point
Shape


Converts text entities to points.


Converts text entities to annotation in the subclass DXF.
Each layer creates a unique annotation level.


Converts attribute and attdef entities to points.


Converts attribute and attdef entities to annotation in the subclass DXF.
Each layer creates a unique annotation level.


Converts inserts to points.


Performs the equivalent of exploding blocks for all points, lines, or multipoint lines.

Text entities within blocks are converted with the Text to Anno or Text to Point options.

Attributes are converted with the Attributes to Annotation or Attributes to Points options.

Inserts cannot be converted to points with this option.


The coverage you will create.


Eliminate

Removes polygons or lines from a coverage by merging them with adjacent features. Features are selected for deletion based on logical expressions or applying the criteria contained in a Selection file.

Eliminate is often used to remove sliver polygons created during polygon overlay or buffering.

  Eliminating polygons

  Eliminating lines

Notes

You can improve performance by indexing the items used in your logical expressions.

To preserve an arc from deletion, assign it a negative User-ID; the next longest arc will be eliminated instead.

How to build a query

How the default fuzzy tolerance is calculated

Related Topics


Eliminating polygons

A deleted polygon’s label point is also removed.

A deleted polygon is merged with the neighboring polygon that has the Longest shared border or the Largest area.

Use the Keep polygons with an outside border option to preserve the outer boundary of polygons that border the universe polygon.

Regions are maintained, but the eliminated polygons are removed from the region subclasses.

Route-systems attached to eliminated polygon arcs are removed, and ARCLINK# is renumbered.


Eliminating lines

Arcs and route-systems can be simplified by removing selected arcs and adding the equivalent distance to the connecting arc that preceeded it in the processing order. The resultant arc assumes the direction of the connecting arc.

All arcs must be split where they intersect other arcs, otherwise Eliminate will abort execution. Use Clean with the Line option to split overlapping arcs.

Route-systems belonging to eliminated arcs (whether actually removed or not) will be deleted. Those belonging to arcs that increased in length by absorbing eliminated arcs will have their F-POS and T-POS adjusted so that they occupy the same set of locations as previously.


Processing order for Eliminate

Eliminate processes coverage features in a top-to-bottom and left-to-right order. Arcs selected for elimination will be merged with the preceeding arc and will assume its directionality.


 A Selection file stores the specifications of the selection criteria to be applied against specific coverages and INFO data files. It does not store the actual selected features or records, only the selection methods. Selection files are created with the WRITESELECT command in ARCPLOT.


 A sliver polygon is a small areal feature commonly occurring along the borders of polygons following a topological overlay operation where the polygon boundaries do not match exactly. Buffering can also produce sliver polygons.


The universe polygon is the first record in a polygon attribute table. It represents the area beyond the outer boundary of the coverage. It’s the only polygon that never has a label point, and so has a User-ID value of 0. Its area equals the negative sum of all the polygons in the coverage. Also referred to as the external polygon.


The coverage with polygons or arcs you want to merge with neighboring features.


The coverage you will create.


Choose how you want to select features.

Build a query – use the Query Builder to create one or more logical expressions that select the features you want to merge.

Selection file – use a pre-existing file that identifies the features you want to merge.


The feature classes available for merging.

Poly – merges selected polygons.

Line – merges selected lines.


Choose whether you want to keep polygons with an outside border.

Checked – maintains all selected polygons that border the universe polygon.

Unchecked – allows the elimination of selected polygons that border the universe polygon.


Choose how you want to merge adjacent polygons.

Longest shared border – merges a selected polygon with a neighboring unselected polygon with the longest shared border.

Largest area – merges a selected polygon with a neighboring unselected polygon with with the largest area.


Opens the Query Builder to build or edit a logical expression.


Lists the expressions you have built.


Erase tool
Erase

Creates a new coverage by overlaying the polygons of the Erase coverage with the features of the Input coverage. Only those portions of the Input coverage features falling outside the erase polygon outside boundaries are copied to the Output coverage.

Erase discovers the feature classes in the Input coverage and offers the available erasing methods:

Poly – splits the input polygon arcs where they overlap the erase polygons, drops the arcs inside the erase polygons, and builds the remaining arcs into a new polygon coverage. Label points lying outside the erase area are retained, and new polygon label points are generated as required.

Input region subclasses are maintained and erased. They are maintained as empty subclasses when all the regions have been removed.

Route-systems are ignored.

Line – splits the input arcs where they overlap the erase polygons, drops those portions inside the erase polygons, and builds the remaining arcs into a new line coverage.

Route-systems are duplicated for arcs split into multiple pieces, and eliminated for removed arcs.

Point – points inside the erase polygons are dropped, and the remaining points are built into a new point coverage.

Poly & Line (Net) – polygons and arcs are erased. Polygon topology is rebuilt with an updated PAT and AAT. Route-systems are maintained.

Line & Point (Link) – arcs and points are erased. Line topology is rebuilt with an updated AAT and PAT.

Geometry – arcs, data points and annotation in a coverage with or without topology (no attribute files) are erased. Route-systems are maintained but regions, PAT and AAT are not saved.

Notes

Annotation is erased if its lower-left starting point falls within the erasing polygon.

New nodes have their attributes set to zero.

How the default fuzzy tolerance is calculated

Processing planar graphs

Related Topics


The outside boundaries of the Erase coverage define the area of Input coverage features to be removed. Any Erase coverage polygon with an internal number greater than 1 is considered inside the erasing window; an internal polygon number of 1 is considered outside.


The coverage with features you want to remove.


Choose the features you want to erase:

Poly – polygons

Line – arcs

Point – points

Poly & Line (Net) – polygons and arcs

Line & Point (Link) – arcs and points

Geometry – arcs, data points, and annotation in a coverage with or without topology.


The outer polygon of this coverage defines the erasing area.


The coverage you will create.


Etak to Coverage

Converts an Etak MapBase file to a coverage.

Notes

Output coordinates are in decimal degrees of latitude and longitude.

An attribute table named <Output coverage>.ACODE is created by this tool. Attributes associated with polygons in the Etak file are also contained in the ACODE table and can be associated with each polygon using each arc’s left-right polygon identifiers.

Landmark coverage point attributes are saved in an INFO table named <Landmark coverage>.PCODE. These attributes can be related to each point by the User-ID.

The coverage produced by this tool requires further processing to build topology and to join the code table into the coverage AAT and PAT. Typically, Build using both the Poly and Line options will be adequate to build feature topology. However, there may be errors in the coordinates which require the use of the Clean tool. Since all Output coverage attributes are stored in the ACODE table, a number of steps may be required to create feature attribute tables and an address coverage.

Etak feature types

ACODE table items

PCODE table items

Supported file extension

Related Topics


The Etak file you want to convert to a coverage.


The coverage you will create.


The coverage you will create from landmark features in the Etak file.


Etak Features

The four feature types are DIME or D types, Alternate address or A types, Shape features or S types, and Landmark or L types. If the feature type is D, an arc is created along with a corresponding ACODE record. Shape (S) records are used to add vertices to the arcs. If the feature type is A, then a record is added to the ACODE file. Each A record contains an alternative address record for an arc. (This is useful when building address coverages in ArcInfo NETWORK.) If the feature type is L and a Landmark coverage was specified, then a point feature is created along with an associated PCODE record.

The type of feature or class of road is stored in the item called ROAD.CLASS. The classifications are meant to correspond to differences in driving and may vary in exact meaning from locality to locality. The possible values for ROAD.CLASS are

Class	Description

1 or A	Interstate highway or equivalent

2 or B	Major highway (limited access or partly limited access)

3 or C	Access (providing access to limited access highways) or minor highway

4 or D	Arterial or collector

5 or E	Local street

6 or F	Unpaved

8	Railroad

9	Ramps (access from class 3 to 2 and 1)

S	Shoreline

P	Political boundary

Z or Y	Artificial boundaries at geographic limit of database or to partition large 2-cells (the areas to the left and right of an arc)

Q	Incomplete feature; coordinates are correct but other information is suspect.

N	Incomplete feature; coordinates incorrect but street name and address are correct


ACODE table items

COL ITEM NAME  WDTH OPUT TYP  DESCRIPTION
1 out_cover-ID    4    6  B   User-ID of each arc
5 TYPE            1    1  C   The Etak record type
6 CLASS           1    1  C   The road class
7 ETAK.ID         8    8  I   Etak ID number
15 NAME          50   50  C   Street or feature name
65 F-NODE         8    8  I   Etak start node number
73 F-X           11   11  C   X-coordinate of the from node
84 F-Y           11   11  C   Y-coordinate of the from node
95 T-NODE         8    8  I   Etak end node number
103 T-X          11   11  C   X-coordinate of the end node
114 T-Y          11   11  C   Y-coordinate of the end node
125 L-POLY        8    8  I   Etak number of left polygon
133 L-F-ADD      10   10  I   Left address at from-node
143 L-T-ADD      10   10  I   Left address at to-node
153 L-STATE       2    2  C   Left state code
155 L-MSA         4    4  I   Left Metropolitan Statistical Area
159 L-COUNTY      3    3  I   Left county name
162 L-MCD         3    3  I   Left Minor Civil Division
165 L-PLACE       4    4  I   Left place name
169 L-ZIP         9    9  I   Left ZIP code
178 L-TRACT       6    6  I   Left track number
184 L-BLOCK       3    3  I   Left block number
187 R-POLY        8    8  I   Etak number of right polygon
195 R-F-ADD      10   10  I   Right from address
205 R-T-ADD      10   10  I   Right to address
215 R-STATE       2    2  C   Right state name
217 R-MSA         4    4  I   Right SMSA
221 R-COUNTY      3    3  I   Right county name
224 R-MCD         3    3  I   Right MCD code
227 R-ZIP         9    9  I   Right ZIP code
236 R-TRACT       6    6  I   Right tract number
242 R-BLOCK       3    3  I   Right block number
245 SHAPE.COUNT   4    4  I   Number of shape points
249 ONEWAY        1    1  C   One-way code
250 INTERPOL      1    1  C   The address range interpolated
251 RESERVED      6    6  C   Reserved for future use


PCODE table items

COL ITEM NAME      WDTH OPUT TYP  DESCRIPTION
1 landmark_cover-ID   4    5   B  Landmark coverage User-ID.
5 TYPE                1    1   C  The type of feature
6 CLASS               6    6   C  Landmark class described below
12 ETAK.ID            8    8   I  Etak ID of the landmark feature
20 NAME              50   50   C  Landmark name
70 X                 11   11   C  X-coordinate of feature location
81 Y                 11   11   C  Y-coordinate of feature location
92 CELL.COUNT         2    2   I  Number of other Etak features (up to 10)
94 CELL1.DIMENSION    1    1   I  Referenced feature type
0 = point
1 = line
2 = polygon

95 CELL1.ID           8    8   I  References Etak ID of one of the features defining the landmark

103 CELL2.DIMENSION   1    1   I  Remaining feature references in these items
104 CELL2.ID          8    8   I
112 CELL3.DIMENSION   1    1   I
113 CELL3.ID          8    8   I
121 CELL4.DIMENSION   1    1   I
122 CELL4.ID          8    8   I
130 CELL5.DIMENSION   1    1   I
131 CELL5.ID          8    8   I
139 CELL6.DIMENSION   1    1   I
140 CELL6.ID          8    8   I
148 CELL7.DIMENSION   1    1   I
149 CELL7.ID          8    8   I
157 CELL8.DIMENSION   1    1   I
158 CELL8.ID          8    8   I
166 CELL9.DIMENSION   1    1   I
167 CELL9.ID          8    8   I
175 CELL10.DIMENSION  1    1   I
176 CELL10.ID         8    8   I
184 RESERVED         77   77   C


Etak’s MapBase is a digital street centerline map product that is similar in content to the GBF/DIME format used by the U.S. Census Bureau. Each record represents a single linear feature with addresses and political, census, and ZIP code boundary information. Etak has also included road class designations and, in some areas, major landmark features.


Coverage to Geodatabase Wizard
Route Event Table to Feature Class Wizard

Converts point or line events into a point or line feature class and assigns it the ESRI Simple Feature Class behavior.

An event is a row in a table that has a route location. A route location describes a portion of a route (line event) or a single location along a route (point event). Events are stored in a file known as an event table. This can be an INFO, a dBASE, or a geodatabase table.

Related Topics


Route event table

The Input route event table can be an INFO, dBASE, or geodatabase table.


Route event type and associated attributes

Point events are converted to a collection of simple features with Multipoint M geometry. A Multipoint is a set of points that represent one feature with a common set of attributes and has a number of x, y, m coordinate values.

Line events are converted to a collection of simple features with Polyline M geometry.  The Polyline is an ordered collection of paths that can be disjoint or connected.

When selecting the event type, the Event key field identifies which route the event is on. It can be any numeric or text field. For Point events, the Location field specifies the measure values. For Line events, From-M and To-M fields are specified. Measure fields can be any numeric type. An optional offset field can be used to laterally offset each event from the route.


Route feature class

Routes are stored in a route feature class. A route is any PolyLine feature that stores M values. Events are defined upon the routes in a Route feature class. You can browse to select any route feature class.  The route key field is required. It matches values in the event key field.  Like event key field, this can be any numeric or text field.

Values in the route key field are unique: Route keys may or may not be unique within a route feature class. For routes stored in a personal or ArcSDE geodatabase, locating route events will be faster if the route keys are unique. However, if your data does not have unique route keys (or you are unsure), do not check this option because the underlying segmentation algorithm will only look for one route with the corresponding route key, if you indicate that the route keys are unique. The event being processed may or may not locate itself on the route feature that was found. NOTE: This setting has no effect for routes stored in a coverage and shapefile.


Output type

The output options are a Geodatabase or a Shapefile.

If Geodatabase, the new feature class can be in a feature dataset or it can be stand-alone. The stand-alone feature class will contain features that have no topological associations with features in other feature classes. For a geodatabase, the domain extent or measure range of a feature class is dependant on the minimum m and precision values. Use the default values or change the Precision, Minimum and Maximum M values.

If Shapefile, the output feature class will contain simple features with no topological associations.

The feature class name or shapefile name cannot begin with a numeric character.


Convert route events

The tool allows you to convert selected or all events. Use the query builder to specify which events to convert.


Supported File Extensions
Supported file extensions for various formats

The following extensions are used for the various data formats supported in the ArcToolbox. These extensions are particularly important when ArcToolbox conversion tools are added to the ArcCatalog. For example, the SDTS to Grid Wizard supports files with an extension of ‘DDF’. This wizard will only work in the ArcCatalog if a custom file type with an extension of ‘DDF’ is selected.

Files dragged and dropped onto Toolbox tools must also have these extensions in order for the dropped files to be valid in a particular tool. In the Floating Point Data to Grid tool, for example, only files with an extension of ‘FLT’ can be dragged and dropped onto it from the Windows Explorer or ArcCatalog.

Data format	Extension

ASCII file	TXT

Arc Digital Raster Grid (ADRG) 	OVR

Atlas Geo File 	AGF

Census Bureau DIME file	GBF

dBASE file	DBF

Digital Elevation Model	DEM

Digital Feature Analysis Data	DFAD

Digital Line Graph (Level 3)	DLG

Drawing Exchange File	DXF

Etak MapBase	ETAK

Floating point data file	FLT

Interactive Graphics Design Software 	DGN

  (Microstation Design File)

MapInfo Interchange Format	MIF

MOSS public domain GIS	MSS

Spatial Data Transfer Standard	DDF

Standard Linear Format	SLF


Extract Wizard

The Extract Wizard will guide you through the process of reselecting map features from an Input coverage, based on feature attribute values. The Feature class that you select from the Input coverage will be in the Output coverage. You will use the Query Builder to create the set of attributes to extract.

Line or point features

Line features include routes, sections and annotations.

Area features

Area features include polygons and regions.

Related Topics


Subclasses

Specify a unique name for a new region subclass in each Input coverage. Each polygon in that coverage becomes a region in the specified region subclass. You need to specify a Subclass name to use polygon attribute values in the query or dissolve panels of the wizard.


Overlay functions

When two subclasses are used, the Extract Wizard (AREAQUERY) can mimic classical overlay functions of Intersect, Union, Identity, Clip, and Erase.

Intersect

Intersect finds what's common between two coverages. All items beyond the <COVER>-ID are copied to the Output coverage. The Output coverage contains all the polygons of the Input Coverages. The Subclass specified with the Output coverage name will have the shared attributes of the subclasses specified on the next panel.

Union

Union combines the attributes of up to thirty-two polygon coverages into one coverage. To preserve attributes, specify a subclass name for each coverage and include the attribute items in the list of output items.  All items beyond the <COVER>-ID are copied to the Output coverage. The Output coverage contains all the polygons of the input coverages and the output subclass represents the union area.

Identity

Identity computes the intersection of the input coverages by integrating them and finding those features of the non-identity subclasses that intersect with the identity subclass. It preserves ALL the identity subclass features. The identity operation varies based on which region subclass is the ‘identity’ class.

Clip

Clip extracts those features from an Input coverage that overlap with a Clip coverage. Multiple coverages are integrated, then the 'clip' subclass is used to 'clip' the other subclasses.

Erase

Erase removes the Input coverage features that overlap the Erase coverage polygons. Multiple coverages are integrated, then those portions of subclasses that overlap with the ‘erase’ subclass are removed.


Attribute items

Choose names of items selected from the various region polygon attribute tables (PATs) or the polygon PATs of the Input coverages. Attribute value combinations of these items will be unique for each output region and are written to the Output coverage subclass PAT.

Select "*" to include all items of that subclass PAT.

A final dissolve is performed based on the list of Output items. Each item in the list is inspected, and all items associated with it are returned. For a redefined item, the Extract Wizard (AREAQUERY) will include the normal items that support it. For a normal item, it includes all redefined items that overlap. This set constitutes the output items. As a result, the output may have greater granularity than indicated by the input items alone.

When the items are written to the subclass PAT, the prefixes are stripped off, unless there is a conflict of names between two or more subclasses. In this case, the prefixes are maintained.


Tolerance

Specify the minimum distance between arc coordinates in the Output coverage.

The default value shown is taken from an Input coverage TOL file. If a TOL file does not exist, the tolerance is calculated to 1/10,000 of the width or height of the map extent, whichever is greater (BND). If the BND is undefined, the tolerance is set to 0.001.

The Extract Wizard will not accept a tolerance value of 0.

If the specified tolerance is too large, Input coverage polygons may not be preserved in the Output coverage.


Output coverage

Region subclasses transfer to the Output coverage only if you have specified an attribute from that subclass on the Attribute item panel, or you have used the subclass in the query.

The AAT, NAT and route-systems of the input coverages are NOT maintained in the Output coverage.

The Wizard rewrites TICs from all input coverages to the Output coverage. Starting with the second input coverage, TIC User-IDs update according to an offset value determined by adding one to the value of the last TIC read. If, for instance, the last TIC had a User-ID of 5, TICs in the next set would increment by 6.


Feature Class to Geodatabase

Loads a feature class into a Geodatabase as a stand-alone feature class or into a feature dataset.

The output Coordinate System is determined from the Input feature class. This can be modified if you are loading the feature class into a new feature dataset or a stand-alone feature class. If you are loading into an existing feature dataset, these parameters cannot be altered.

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings…. You may also choose to not include certain columns from the input table in the new Geodatabase table.

This process does not preserve object identity and always results in a simple feature class that contains no subtypes, default values, and so on.

Notes

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the Geodatabase you specify and whether you are using SDE or Access.

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Spatial Reference and Domain extents

Spatial index grid

Related Topics


The feature class you want to load into a Geodatabase.


The Geodatabase into which you want to load the Input feature class.


The feature dataset into which you want to load the feature class; it is optional.


The output feature class you will create.

The feature class name cannot begin with a numeric character.


Provides access to the Output Settings dialog, where you can view and change the spatial reference, change the Grid Size, and edit the items of the output feature class.


Standard field-to-item data type mapping

dBASE data types	ARC/INFO data types

Type	Width	Output + Dec	Type	Width	Output	Dec

Character	<expC>	(n)	C	n	n	-

Numeric	<expN>	(n,m)n<=7	F	4	n	m

n<=7,m=0	B	4	n	-

n>7	F	8	n	m

Date	<expD>	D	8	10	-

Logical	condition>	B	2	5	-

Memo	<expM>	C	10	10	-


Find Building Conflicts

Searches a region coverage for overlapping and closely-spaced buildings, based on a specified distance, and records the occurrences.

The tool is used for post-processing of output from the Simplify Buildings tool. The tool creates a buffer around each building or group of connected buildings. The areas where buffers overlap indicate a conflict. The overlapping areas are assigned a FREQUENCY value of 2 or more in the Output coverage polygon attribute table (PAT), according to how many buffers overlap. A value of 1 indicates a non-conflicting area.

Notes

The Input coverage should be the result of the Simplify Buildings tool, which creates the preliminary region subclass BLDGSIM, and the Clean tool, which creates region topology.

The Output coverage is created only if conflicts are identified. It contains the region subclass BUF for the buffered regions. The <Output coverage>.PAT contains the item FREQUENCY to store the number of conflicts.

Buildings connected in one group are not considered as conflicting with each other. Only the outer boundary of such a group will be checked with neighboring buildings or groups of buildings.

Example

Related Topics


Choose the coverage with buildings that are overlapping or too close together. It must have region topology and contain the item BDS-GROUP in region subclass BLDGSIM.


Buildings within this distance of each other will be marked as conflicting. The value—in coverage units—must be greater than zero (0).


The coverage you will create.

NOTE: It is only created if conflicts are identified.


Example of buildings analyzed with the Find Building Conflicts tool


Floating Point Data to Grid

Converts an IEEE floating point format, 32-bit signed file of binary floating point numbers into a grid.

Notes

 An ASCII header file that has the same name as the Input float file with an extension of “hdr” is required. The file must be in the same directory as the floating point file and consist of header information defined by a set of keywords.

 The NODATA_value is the value in the input file that denotes that those cells should be assigned the value of Nodata in the output grid. Nodata is normally reserved for cells whose true value is unknown.

 Supported file extension

Related Topics


The floating point file you want to convert to a grid.


The grid you will create.


ASCII header file format

<NCOLS xxx>
<NROWS xxx>
<XLLCENTER xxx | XLLCORNER xxx>
<YLLCENTER xxx | YLLCORNER xxx>
<CELLSIZE xxx>
{NODATA_VALUE xxx}
BYTEORDER <MSBFIRST | LSBFIRST | VMS_FFLOAT>

where xxx is a number, and the keyword NODATA_VALUE is optional.


Frequency

Searches an Input table for unique occurrences of one or more Frequency items. For each unique combination of values found, a record is generated in an Output table listing the case number, the unique combination found and the number of times the combination occurs. You can also append the total value of one or more Summary items for all instances of that combination.

Frequency is useful during the initial examination of a table to see what values it contains, or as an aid in classification to help identify cases that are not different. It can also be used to identify unusual cases for closer examination.

Notes

The Output table contains the following items:

Case item (4,5,B), with a default name of CASE#. Or you can specify any name when you choose For both input and output table to also append this item to the Input table.

FREQUENCY (4,5,B), containing the number of times each unique combination occurs.

Frequency items and their unique combination of values.

Summary items (8,18,F,6), and their total value for each unique occurrence of the Frequency items.

The value attribute table (VAT) is the only valid Input table for a grid.

Example

This example searches the Input table LANDUSE.PAT, for combinations of the Frequency items LU-CODE and COST/HA. The Summary item AREA is added to the Output table LANDUSE.TAB. Note that the Case item TABLE# has been appended to LANDUSE.PAT.

LANDUSE.PAT

Record   AREA  LANDUSE#  LANDUSE-ID  LU-CODE  COST/HA  TABLE#
1      10,000         1           0      100    15000       1
2      40,000         2           1      300    30000       4
3      15,000         3           2      200    30000       3
4      20,000         4           3      100    15000       1
5      22,000         5           4      100    20000       2
6      13,000         6           5      100    15000       1
7      50,000         7           6      400    45000       5
8      30,000         8           7      200    30000       3

LANDUSE.TAB

$RECNO TABLE#  FREQUENCY   LU-CODE   COST/HA   AREA
1      1         3            100    15,000   43000
2      2         1            100    20,000   22000
3      3         2            200    30,000   45000
4      4         1            300    30,000   40000
5      5         1            400    45,000   50000

Related Topics


The table with the items you want to count.


The table you will create.


The Case item contains the case number for each unique occurrence of the Frequency item(s). Choose which tables will have this item.

For output table only – adds the item named CASE# to the Output table.

For both input and output table – adds the item name you specify in New item name to both tables. The Case item in the Input table contains the Output table record number to which that Input table record was classified. You can use the Case item to link the two tables.


Lists the items available to identify unique code combinations.


Choose the items whose unique code combinations you want to identify.


Lists the items available to summarize item values over all unique occurrences of the Frequency items.


Choose the items you want to summarize for unique occurrences of the Frequency items.


Check the box to show only the Frequency items you have selected.


Check the box to show only the Summary items you have selected.


Specify a name for Case item. This item is added to both the Input table and the Output table.


Geodatabase to Coverage

Converts a geodatabase feature class to a coverage.

The Input can either be a stand-alone feature class or a feature dataset containing one or more feature classes. If the input is a stand-alone feature class, the option Export each feature class to its own coverage creates a single output coverage. If the input is a feature dataset containing several feature classes, the tools batch grid is automatically populated and opened and you can either export each feature class to its own coverage or Merge all feature classes into a single coverage.

Notes

Multiple feature classes from different feature datasets can be entered simultaneously.

The Merge all feature classes into a single coverage option lets you merge several feature classes into one coverage. When selecting composite feature classes such as region and route, note that there must be a one-to-one mapping between the input feature classes and the output subclass. It is not possible to merge all input feature classes into one output subclass.

Annotation feature classes can be written to existing coverages if only annotation features are being converted. If annotation features are converted with other feature types, such as point or line and the Merge all feature classes into a single coverage option is selected, a new coverage must be created.

For detailed information on field type to item mapping between geodatabase and coverages, click here

The attributes in a geodatabase annotation feature class will be converted to a corresponding coverage annotation subclass Text Attribute Table (TAT). The coverage annotation pseudo items ($SIZE, $SYMBOL, etc) will be populated as well. The size of each annotation feature will be converted from the unit points to a corresponding size in map units. Note that the size is closely related to the font being used. ArcMap provides many symbol properties that are unavailable in Workstation ArcInfo, such as fill pattern, advanced background options, and shadow. Therefore, only those properties supported by Workstation ArcInfo can be retained.

To create a corresponding textset for use with ArcInfo workstation (Arcplot and Arcedit), use the information in a text file that is created in the same directory as the output. This file contains a list of the unique symbols used by the annotation features. It specifies the font, style, color, etc for each symbol. The file is named <output coverage>_<subclass>.sym. You can find a sample AML that automates this process in http://gis.esri.com/arcscripts/index.cfm Language: AML, Software: ArcInfo Workstation, Category: Graphics and Symbols, Keyword: Annotation.

Related Topics


The name of the feature class or feature dataset containing the feature class you want to convert to a coverage.


The name of the Ouput coverage to be created.


The coverage feature class to be created.


A Subclass Name is required for feature classes Region, Route and Section, and is optional for Annotation.


Choose if you want multiple feature classes in a geodatabase dataset to be converted to separate coverages or merged into one coverage.

Export each feature class to its own coverage: each feature class will be exported to it’s own, individual coverage.

Merge all feature classes into a single coverage: all the feature classes will be merged into a single output coverage.


Geodatabase to Shapefile

Converts a geodatabase feature class to a shapefile.

Notes

You can only convert one feature class to a shapefile.

For detailed information on field type mapping between geodatabase and Shapefile and dBase, click here

Related Topics


The name of the geodatabase feature class or dataset you want to convert to a shapefile.


The name of the shapefile you will create.


Geodatabase to Table

Converts a Geodatabase table to an INFO or dBASE table.

The Default Geodatabase to INFO item type mapping

The Default Geodatabase to dBASE item type mapping

Notes

The maximum record length for an INFO table is 4096 bytes; for a dBASE table it is 4000 bytes. When the limit is exceeded, the table is converted, but the tool issues a warning message after the conversion that the table may be unusable.

INFO table item names are limited to 16 characters in length, dBASE item names are limited to 10 characters. Item names longer than the stated limits will be truncated at those limits.

If an item name is used more than once in the Output table, possibly due to truncation of item names exceeding the limit, the last 2 characters in the item name will be replaced by an underscore “_” and a number.  The number will start with 1, and increase sequentially making each redundant item name unique. Example

The maximum number of fields for a dBASE data file is 255. The tool will convert only the first 255 items if this dBASE limit is exceeded.

BLOBs are not supported in INFO or dBASE.  Fields defined as BLOB data type will not be converted.

Related Topics


The geodatabase table you want to convert.


Choose an Output table type:

INFO creates an INFO table.

dBASE creates a dBASE table.


The table you will create; it will be the type selected in Output table type.


Default mapping Geodatabase to INFO

The data types between Geodatabase and INFO differ, making it necessary to map Geodatabase item data types into the appropriate INFO field types. The field data type conversion is as follows:

Geodatabase	   INFO	          INFO	     INFO	INFO
Data Type	Item Type    Item Width   Output Width   No. Dec

Object ID	      B	4	       9	  -
Short Integer	      B	2	       5	  -
Long Integer	      B	4	       9	  -
Float	      F	4	       12	  3
Double	      F	8	       18	  5
Text	      C	255	       255	  -
Date	      D	8	       10	  0
Blob	      NA	NA	       NA	  NA


Default mapping Geodatabase to dBASE

The data types between Geodatabase table and dBASE differ, making it necessary to map Geodatabase item data types into the appropriate dBASE field types. The field data type conversion is as follows:

Geodatabase	         dBASE	         dBASE
Data Type	       Item Type	      Item Width

Object ID	N	9
Short Integer	N	4
Long Integer	N	9
Float	F	13
Double	F	19
Text	C	255
Date	D	8
Blob	NA	NA


Example of truncation of field names and unique field name creation.

Geodatabase Field Names 	Output INFO Field Names
Hydrometric_Station_ID	Hydrometric_Stat
Hydrometric_Station_Name	Hydrometric_St_1
Hydrometric_Station_Type	Hydrometric_St_2

Geodatabase Field Names	Output dBASE Field Names
Hydrometric_Station_ID	Hydrometri
Hydrometric_Station_Name	Hydromet_1
Hydrometric_Station_Type	Hydromet_2


Generalize Lines
Simplify Lines

Reduces details from lines and polygon boundaries based on a specified tolerance and simplification method. If polygon topology exists for the Input coverage, it is not preserved in the Output coverage; however, it does preserve the polygon attribute table (PAT).

The Weed tolerance determines the degree of simplification. To produce cartographic outputs, set the Weed tolerance equal to or greater than the threshold of separation, i.e., the minimum allowable spacing between graphic elements. For other display or for data reduction, we recommend that you experiment with a variety of values to find a suitable Weed tolerance.

The tool provides two line generalization methods:

Remove points – keeps the so-called critical points that depict the essential shape of a line and removes all other points. The tool uses a published algorithm (Douglas and Peucker, 1973) with enhancements to connect the end-nodes of an arc with a “trend line”. The distance of each vertex to the trend line is measured perpendicularly. Vertices closer to the line than the tolerance are eliminated. The arc is then divided by the vertex farthest from the trend line, which makes two new trend lines. The remaining vertices are measured against these lines, and the process continues until all vertices within the tolerance are eliminated. .

This method is efficient for data compression and for eliminating redundant detail; however, the line that results can contain sharp angles and spikes which reduce the cartographic quality of the line.

Use this option for relatively small amounts of data reduction or compression and when you don’t need high cartographic quality. To view an example, click [image].

Remove curves – applies shape recognition techniques that detect bends, analyze their characteristics, and eliminate insignificant ones. A bend that is too narrow will be widened slightly to satisfy the tolerance. The resulting line is more faithful to the original and shows better cartographic quality.

Use this option if you need high cartographic quality. To view an example, click [image].

If the Check for topological errors option is checked, the process will stop and a message will be posted if topological errors are encountered during simplification of the lines.  Topological errors include lines crossing, lines overlapping, zero-length lines, collapsed polygons, and holes falling outside of polygons.

Recommended post-processing

To recreate topology and update feature attribute tables, use the Build tool.

Notes

Regions in the Input coverage are reduced to preliminary regions in the Output coverage.

To preserve the Input coverage, name the Output coverage differently.

Related Topics


The coverage with lines you want to generalize.


The Weed tolerance determines how much detail will be removed from lines or polygon boundaries. The value is in coverage units and must be greater then zero (0).


Choose a Simplification method:

Remove points removes redundant detail to create simplified lines or polygon boundaries, while preserving their essential shape. The resulting lines can have sharp angles and spikes. Use this option for data reduction and if you do not need cartographic quality output.

Remove curves removes unwanted curves from lines and polygon boundaries with a more refined method. The resulting lines are therefore more truthful to their original shape. Use this option if you need high cartographic quality output.


The coverage you will create. If it is the same name as the Input coverage, the Input coverage will be replaced.


Example of line simplification using vertex removal algorithm.


A generalized line created with the Remove points option


A generalized line created with the Remove curves option


Specifies whether to check for topological errors or not.


David H. Douglas and Thomas K. Peucker, ‘Algorithms for the Reduction of the Number of Points Required to Represent a Digitized Line or Its Caricature’, Canadian Cartographer, 10, No. 2 (December 1973).


Generate to Coverage Wizard

Converts an ASCII file to a coverage or adds features to an existing coverage. The wizard provides an easy mechanism to create coverages from raw coordinates or add features to existing coverages. This means that any coordinate data can be loaded into a coverage as long as you can put the coordinates into the appropriate Generate format. For example, to generate lines, you would need to create a text file that has a User-ID number for each line, followed by the series of xy coordinate pairs that define the line.

A coverage created by the Generate to Coverage Wizard is similar to a coverage created by digitizing, as topology has not yet been defined for the features in the coverage. Other tools such as Build or Clean can be used to create the topology.

Notes

When generating features for an existing coverage, the coordinate precision for new features will be the same as the coordinate precision of the existing coverage.

To add tics to a coverage without replacing existing tics, choose feature class Tics and do not copy tics from an existing coverage. Note: a generated tic will replace an existing tic if the ID numbers are the same.

While processing duplicate tics with the same ID number, the last tic read with the same ID number is the one whose coordinates are stored in the coverage tic file.

Generated Polygons will be closed automatically from the last vertex entered to the first vertex, if the two vertices are not the same.

The wizard updates the boundary of the coverage (BND) to include all the newly generated features. Tics for the coverage will be defined at the four corners of the coverage boundary unless: tics already exist, or are generated by choosing Tics, or are copied from an existing coverage.

Coordinates read from a text file can be in x y z format. The wizard ignores the z values if they exist.

Related Topics


Descriptions of input for different features:

  Annotation

  Circles

  Curves

  Fishnet

  Lines

  Links

  Points

  Polygons

  Routes

  Tics


Annotation

Adds annotations to the coverage.

Anno ID - The ID number for the annotation being added.

X and Y coordinates - identifies the coverage coordinates for the lower-left beginning point of the text string being entered.

Angle - is the text angle given in degrees counterclockwise from the horizontal, which is zero degrees. If angle is 0, generated annotation will be one-point annotation. If angle is other than 0, generated annotation is two-point annotation.

Size - is the annotation height in coverage units. Note: The wizard will not verify that the size value you enter for annotation is given in coverage units. Be sure you enter Size correctly.

Text - is the text string to be generated.

Click the Add Anno button to define another annotation.


Circles

Generates circles, each with a specified center and radius.

Enter a circle by specifying the Circle-ID, the X and Y coordinates for the center of the circle, and the Radius. The Radius is specified in coverage units. The Circle-ID will be assigned to both the arc and the label. Click the Add Circle button to define another circle.

When Add Labels is checked, labels will be added at the center of each circle, and the Anno ID will be assigned to both the arc and the label.


Curves

Generates curves using the specified grain value as the distance between vertices on each curve. The grain value must be a positive integer or real number. The default value is 1.

There are two types of curves:

Center - the specified points include the starting point of the curve, a center point around which the curve is generated, and the ending point on the curve (i.e., curves are clockwise and circular). This is the default method for curve generation. Center curves are specified with Curve ID, Start (X,Y), Center (X,Y) and End (X,Y).

Along - all three points occur along the curve (i.e., all three points are fit through the curve). Along curves are specified with Curve ID, Start (X,Y), Along (X,Y) and End (X,Y).

Use the Add Curve button to begin defining another curve.


Fishnet

Creates a fishnet of rectangular cells. Nodes are created at intersection points of each cell.

Origin (X,Y) - the fishnet origin is the lower-left corner of the fishnet.

Y axis (X,Y) - a point on the positive y-axis from the origin point and is used to orient the fishnet.

Cell size - refers to the size of the cells in the x and y directions. Cell sizes are expressed in coverage units and should reflect the map projection of the coverage. As an example, a cell size of 0.5 is half of a degree in geographic, but 0.5 meters in UTM.

If 0 is entered for Cell size, then it will be automatically computed based on Rows, Columns and Corner (X,Y).

Rows and Columns – the values are used with the Cell size to determine the size of the fishnet.

If 0 is entered for the number of Rows and Columns, the specified Cell size will be used to automatically calculate how many rows and columns can fit within the area defined by the origin and the upper-right corner without exceeding the corner coordinates.

Corner (X,Y) – the upper-right corner of the fishnet.

When Add Labels is checked, labels will be added at the center of each fishnet cell.


Lines

Adds arcs to the coverage.

Enter the Line ID for the line feature then enter the X coordinate and Y coordinate pairs.

Use the Add Coord button to add another coordinate to the same line.

Use the New Line button to begin the definition of a new arc.


Links

Adds links to the coverage. Links are defined by two coordinate pairs: Start X,Y and End X,Y.

Enter a coordinate for each, then click the Add Link button to define another link.

Identity links can be added by specifying the same coordinates for both X,Y pairs.


Points

Adds points to a point coverage, or label points to a polygon coverage.

Enter the Point ID and X,Y coordinates for each point feature. Click the Add Point button to define another point.


Polygons

Adds polygons and label points to the coverage.

Enter a Polygon ID and the Label X,Y coordinates for the polygon label. Then enter the X,Y coordinate pairs for each vertex along the polygon boundary. If 0 is entered for Polygon ID, Label X coord and Label Y coord, then no polygon label will be generated for that polygon.

Click the Add Coord button to add another coordinate to the same polygon.

Click the Add Poly button to define a new polygon.

Do not use a Polygon ID = -99999. This has a special meaning. The Coverage to Generate File tool, when used on polygons, flags all island polygons with this special ID. The Generate to Coverate Wizard will ignore all polygons with an ID of -99999.

Polygons will be closed automatically from the last vertex entered to the first vertex, if the two vertices are not the same.

The User-ID of the arcs that make up the newly generated polygon features will be zero.


Routes

Creates arcs from X,Y coordinate data and defines routes on them.

Specify the Route ID (the value of the User-id in the route attribute table (RAT)). Enter a Measure value, an X coordinate value, and a Y coordinate value. Click the Add Coord button to add another section to the route.

Click the Add Route button to define a new route.


Tics

Adds tics to the coverage.

If you choose the option to copy tics from an existing coverage, you cannot also add tics interactively.

If you choose the option to copy tics, then decide not to, click the Remove button to reset.

Enter a tic by specifying the Tic ID, X coordinate and Y coordinate. Click the Add Tic button to enter another tic.


Coordinates and feature definitions will be read from a text file. This information must begin on the first line of the file and be in the same format as if prompted from the terminal, in integers and real numbers. Geographic coordinates in degrees, minutes and seconds (DMS) must be converted to decimal degrees before they can be used as input coordinates.


Copying tics

Copying the tics from a specified coverage to the Output coverage will delete any existing tics in the generated coverage before copying tics from the specified existing coverage. You may want to copy tics so that the boundary of the new coverage matches that of another. If tics are not copied into the coverage or generated using the Tics option, the boundary will be defined using the extents of the features created. Tics will be placed at the 4 corners of the box defining that extent.


Route information

Route name - Name of the route-system to be created or appended to. The name can be any alphanumeric string up to 11 characters long not starting with a number.

Dissolve fuzzy - A numeric distance in coverage units used to dissolve (merge) adjacent sections. Adjacent sections are dissolved if none of the original measure values along the sections are displaced more than this distance from their original location. If no value is specified, no sections are dissolved.

If you want only adjacent sections with equal measure/length ratios dissolved, check the option to combine them.


Annotation information

You can specify the annotation subclass name, level and the text symbol number associated with the set of annotations.

Annotation subclass - Name of the subclass the annotation will be written to. This subclass name can be any alphanumeric string up to 11 characters long not starting with a number. To add annotation to the coverage without specifying a subclass name, leave this option blank. A coverage can have multiple annotation subclasses.

Annotation level - Specifies a storage category. For example, annotation for secondary roads may be stored in a different level than major highways. The level for a piece of annotation may be accessed using the $LEVEL pseudo item in ArcEdit, or by using the LEVEL item in the annotation feature attribute table after using the ArcInfo ADDTEXT command.

Annotation symbol - A text symbol number that defines the display characteristics for font, color, style, slant and quality.


Each route is associated with a measurement system, a linear method consisting of a starting value and other values along the route. Attributes (or events), such as highway accidents, can be positioned on routes using these measures.


A section is a feature class in ArcInfo that is a component of the route-system data model used to implement routes. They form the infrastructure of route-systems much like arcs form the infrastructure of polygons. Sections are the arcs, or portions of arcs, used to define each route.


Grid to ASCII

Converts an integer or floating point grid to an ASCII file. The ASCII file consists of header information containing keywords, followed by cell values in row-major order.

Notes

The end of each row of cell values is terminated with a carriage return in the ASCII file.

The NODATA_VALUE is the value in the ASCII file assigned to those cells with a value of Nodata. This value is normally reserved for those cells whose true value is unknown.

The tool writes out the origin only as LLCORNER. Either LLCORNER or LLCENTER can be used with the ASCII to Grid tool.

Header format and description

Sample listing of an ASCII file

Supported file extension

Related Topics


Sample listing of an ASCII file converted from a grid

NCOLS 480
NROWS 450
XLLCORNER 378923
YLLCORNER 4072345
CELLSIZE 30
NODATA_VALUE –9999
43 2 45 7 3 56 2 5 23 65 34 6 32 54 57 34 2 2 54 6
35 45 65 34 2 6 78 4 2 6 89 3 2 7 45 23 5 8 4 1 62  ...


The grid you want to convert.


The ASCII file you will create.


Lists the numeric grid cell items. Choose the one whose value you want connected to the ASCII file. The default item is VALUE.


Header format and description

<NCOLS xxx>
<NROWS xxx>
<XLLCENTER xxx | XLLCORNER xxx>
<YLLCENTER xxx | YLLCORNER xxx>
<CELLSIZE xxx>
{NODATA_VALUE xxx}
ROW 1
ROW 2
.
.
.
ROW n

where:

NCOLS is the number of columns in the ASCII file.

NROWS is the number of rows in the ASCII file.

XLLCENTER | XLLCORNER is either the x coordinate for the center or lower left corner of the lower left most cell in the grid.

YLLCENTER | YLLCORNER is either the x coordinate for the center or lower left corner of the lower left most cell in the grid.

CELLSIZE is the length of a cell’s edge.

NODATA_VALUE is the value in the ASCII file representing unknown values. It is optional, and defaults to -9999 if not specified.

xxx are numbers, and the cell values are space delimited.


Grid to DEM

Converts an ArcInfo grid to a Digital Elevation Model (DEM) in the United States Geological Survey (USGS) format.

Notes

The Output DEM is an ASCII operating system file with variable length records. Some applications may require the files to be in fixed record length format. Conversion from variable to fixed length format can usually be performed by the operating system. See your system administrator for details.

All Input grid cell sizes with the Nodata value are assigned, per USGS specification, the value of -32767 in the output DEM. In addition, the void area flag (Data Element 25 in Logical Record Type A) of the output DEM is set to the value 2 if any Nodata values are present. If you need to represent Nodata cells with a different value, use the ArcInfo GRID command LATTICEOPERATE with the REPLACE option and a selection expression to change the Input grid z values.

By default, the tool stores a program-calculated spatial resolution value (Data Element 14 in Logical Record Type A) to maintain the highest level of precision possible for the Input grid. This value is used to scale the Input grid’s z values, except the Nodata value, before they are written to the Output DEM’s elevation arrays. The output Nodata value, -32767, is never scaled.

Projection and units information from the Input grid will be transferred to the appropriate data elements in the Logical Record Type A (header record). A value of -9999 will be used for undefined or unsupported parameters.

USGS DEMs do not support all UNITS, ZUNITS and projections options supported by ArcInfo grids.

USGS-supported ground UNITS are:

Radians, Feet, Meters, Arc-seconds

USGS-supported surface ZUNITS are:

Feet and Meters

USGS-supported projections in DEMs

Supported file extension

Related Topics


USGS-supported projections in DEMs

Projection name	ArcInfo keyword

Albers Conical Equal Area	ALBERS
Azimuthal Equidistant	AZIMUTHAL
Equidistant Conic	EQUIDISTANT
Equirectangular (Plate Caree)	EQUIRECTANGULAR
General Vertical Near-Side Perspective	PERSPECTIVE
Geographic 	GEOGRAPHIC
Gnomonic	GNOMONIC
Lambert Azimuthal Equal-Area	LAMBERT_AZIMUTHAL
Lambert Conformal	LAMBERT
Mercator	MERCATOR
Miller Cylindrical	MILLER
Oblique Mercator	OBLIQUE_MERCATOR
Orthographic	ORTHOGRAPHIC
Polar Stereographic	POLAR
Polyconic	POLYCONIC
Sinusoidal	SINUSOIDAL
State Plane	STATEPLANE
Stereographic	STEREOGRAPHIC
Transverse Mercator	TRANSVERSE
Universal Transverse Mercator	UTM
Van Der Grinten I	GRINTEN


The grid you want to convert.


The z-factor states how many ground units in your grid equal one elevation, or z-unit. It is possible that a grid’s ground units are in meters and its elevation units are in feet. Use the value 1 to maintain the grid’s z-units in the DEM. To equalize ground and elevation units, use the z-factor 0.3048 to convert feet to meters, and the z-factor 3.2808 to convert meters to feet. Other USGS-supported ground units are Arc-seconds and radians.


The DEM you will create.


Choose the data type for the elevation in the output DEM:

Floating point – Z-value scaling preserves a Floating point description of the elevations

Integer – Z-value scaling rounds the description of the elevations to the nearest Integer.

Note: Some programs used to read USGS DEMs require an integer description of the elevations.


Every cell location in a grid has a value assigned to it. When adequate information is known about a location relative to the theme of the grid, then the assigned value identifies the zone, thematic category or surface value associated with the location. When inadequate information is available for a cell location for the theme, the location can be assigned to Nodata on the grid representing that theme. Nodata and ‘0’ are not the same; ‘0’ is a valid value. For this reason, Nodata cells cannot be used in calculating the statistics in a grid's STA table.


Grid to Floating Point Data

Converts grid cell values to a signed, 32-bit, binary file in IEEE floating point format suitable for data transfer to other applications. Two outputs are created:

A binary floating point file of cell values.

An ASCII header file containing a set of keywords. The file name is the same as the Output float file plus the extension '.hdr'.

Notes

The Nodata value is always written out as –9999.

To convert Nodata to something other than –9999.

Supported file extension

Related Topics


The Nodata value is the value in the output file assigned to those cells in the input grid which contain the cell value, Nodata. This value is normally reserved for those cells whose true value is unknown.


To convert the Nodata value to something other than -9999

1	Convert Nodata to the desired value with the ISNULL or CON functions in GRID.

2	Convert the grid to a floating point file with the Grid to Floating Point Data tool.

OR

1	Convert the grid to a floating point file with the Grid to Floating Point Data tool.

2	Edit the ‘NODATA_value’ in the ASCII header file to the new value.


The grid you want to convert to floating point numbers.


The floating point file to be created.


The grid cell item you want to represent in the floating point file.


Grid to Image

Converts a grid to a single-band image, or a grid stack to a multi-band image. Grids can be converted to most popular formats, typically with several compression options to reduce file size. Single grids can be converted with a colormap file specifying the color associated with each grid value. A colormap cannot be written for a grid stack.

Colormap options

Available output image formats

Available image compression options

Notes

Compressed images typically require less disk space. However, complex grids may not benefit from compression, actually becoming larger with compression.

The number of bits used to store output pixel values varies between image formats. Binary grids (values 0 and 1) convert to 1-bit images. Non-binary grids convert to 8-bits or higher depending on the output format and the input cell values.

Image formats store unsigned integers. The results are unpredictable if the Input grid contains floating point or negative values. Use the ArcInfo GRID function RECLASS to remap negative numbers to positive, and the INT function to truncate floating point values to integers.

If the values of the input grid are outside the range 0 to 255, no colormap will be written to the output image. Use the SLICE function in GRID to transform the gird values to the appropriate range:

stretchedgrid = slice(grid,eqinterval,256,0)

A world file that stores the image-to-map transformation is created. Some image formats also store this georeferencing information in the image header.

How the BIL, BIP, and BSQ formats handle Nodata values

Related Topics


A grid stack is a set of grids representing various layers of information, referenced by an INFO table. A stack is treated as a single entity for multivariate analysis.


A colormap file is a user-defined ASCII file containing color information. The format of the file is:

cellvalue red green blue

where red, green and blue are integers in the range 0 to 255.


The repeating sixteen Nominal colors are:

0  black        8  orange
1  white        9  light green
2  red         10  pale green
3  green       11  pale blue
4  blue        12  dark blue
5  cyan        13  pale red
6  magenta     14  light gray
7  yellow      15  dark gray


The world file contains the image pixel dimensions and the location of the upper-left pixel with respect to the coordinate system.


How the BIL, BIP, and BSQ formats handle Nodata values

The BIL, BIP, or BSQ formats convert grid Nodata cells to zero values in the image. However, the statistics file (.STX) created during the conversion contains values taken directly from the grid STA file, and therefore, does not reflect the added zero values. Although the image statistics are not strictly correct, the image display will be the same as the original grid.

If accurate .STX values are required, convert grid Nodata values to zeros with the ISNULL and CON functions in ArcInfo GRID before converting the grid to an image.


The grid or grid stack you want to convert to an image.


Available output image formats

BIL - creates a band interleaved by line file.

BIP - creates a band interleaved by pixel file.

BMP - creates a Windows bitmap file. The grid values must fall in the range of 0 to 255.

BSQ - creates a band sequential file.

ERDAS - creates an ERDAS Rev 7.4 image.
If the input grid is a single grid, the output image is a GIS file (.GIS).
If the input is a stack of grids, the output image is a multiband file (.LAN).

IMAGINE - creates an ERDAS IMAGINE image.

JFIF - creates a JPEG-compressed image in JFIF format.

RLC - creates a run-length compressed image. Since an RLC image can only contain pixel values of 0 or 1, all nonzero cell values in the input grid will receive a value of 1 in the output RLC image. Grid stacks can not be converted to RLC format.

SUNRASTER - creates a Sun Raster file.

TIFF - creates a TIFF image.


Available image compression options

Output image      Compression      G4     LZW*

BIL, BIP, BMP,        N/A          N/A    N/A
BSQ, JFIF, ERDAS,
IMAGINE, GRASS

Sun Raster file   Sun run-length   N/A    N/A

TIFF types:

Black and White   TIFF 2         Group 4  TIFF LZW
Grayscale         PackBits         N/A    TIFF LZW
Palette Color     PackBits         N/A    TIFF LZW
True Color        PackBits         N/A    TIFF LZW

JFIF images are always compressed with the JPEG method, yielding high compression ratios but with some data loss (a quality threshold of 75 (on a scale of 0 to 100) is used, resulting in slightly different pixel values after decompression. The JFIF format is best used for grayscale or color images.)

*You must have a license to use the LZW compression option.


The colormap you want to include with the image you will create. A colormap cannot be included for a grid stack.


Colormap options

None – no colormap is included.

Nominal – includes a 16-color map. Use this option if your grid represents nominal or discrete data.

Grayscale – includes a 256-color grayscale map. We recommend that you stretch the input grid to the range of 0 to 255.

Colormap file – includes the colormap file with your color specifications.


The colormap file you want to include with the image you will create.


The image you will create.


Grid to Line Coverage

Converts a grid representing raster linear features to a line coverage. The tool contains a vectorization program designed primarily for conversion of scanned maps and for raster/vector conversion of line features together with the Line Coverage to Grid tool.

Description of tool choices

Notes

The grid's foreground cells form the linear features to be converted to vectors.

Most of the processing of the tool occurs in the raster domain to preserve the accuracy of the original features. It is capable of processing very large grids. Temporary scratch space requirements are minimal since no results are written to disk until the arc assembly begins.

Related Topics


The integer grid you want to convert to a line coverage.


Choose the cells values that will identify the grid’s foreground cells.


Cells with positive values identify the grid’s foreground cells.


All cells, except those with the value Nodata, identify the grid’s foreground cells.


Choose the thinning methods you want to apply to foreground cells.


Choose whether you want to thin the foreground cells before vectorization.

Checked – thins the foreground cells. This influences the maximum line thickness. NOTE: Do not use this option on a grid with line features that are 3 or less grid cells wide.

Unchecked – does not thin foreground cells. This influences the maximum line thickness.


Choose whether you want to apply a filter as the first phase of thinning.

Checked – smoothes the boundaries between the grid’s foreground and background cells. NOTE: Line features that are 3 or less grid cells wide are removed.

Unchecked – no smoothing of boundaries occurs.


If Thin foreground cells is checked, the tool automatically uses a Maximum line thickness value of 10 times the grid cell size.

If Thin foreground cells is unchecked, the tool automatically uses a Maximum line thickness value of 2 times the grid cell size.

Its unit of measure is that of the Input grid.

You achieve best results with a thickness value that is equal to the widest line you want to thin. Enter a value to suit your needs.


The thickness’ unit of measure.


Choose how you want the vectorization process to handle turns.

Checked – smoothes junctions, intersections and corners. Use this option for natural features, such as streams and contours.

Unchecked – preserves rectangular junctions, intersections, and corners. Use this option for man-made features, such as streets and utility networks.


Set the processing tolerances for the line coverage you will create.


A dangling arc must at least be as long as the dangle length to be retained in the coverage you will create. The tool removes dangling arcs that are shorter than the Dangle length.

If Thin foreground cells is checked, the tool automatically uses a dangle length of 0.7.

If Thin foreground cells is unchecked, the tool automatically uses a dangle length of 0.

Its unit of measure is that of the Input grid.

Enter a value that suits your needs.


The dangle length’s unit of measure.


Two vertices on an arc must at least be as far apart as the Weed tolerance to be retained in the coverage you will create. The tool removes vertices that are closer together than the weed tolerance. The resulting arc’s shape is typically more straight. The arc is generalized.

Its unit of measure is that of the Input coverage.

You must use a value equal to or greater than 0. We recommend a value that is smaller than (2.5 times cell size).


The weed tolerance's unit of measure.


If you want to transfer the values of the grid cell item VALUE to the Output coverage AAT, specify a name for the new AAT item. No values are transferred if an item name is not provided.


The line coverage you will create.


Description of tool choices

Set as foreground cells - Specifies the cell values that will identify the foreground cells. The grid is viewed as a set of foreground cells and background cells. Foreground cells form the linear features to be converted to vectors.

Cells with positive values – All cells whose VALUE is greater than zero belong to the foreground. All cells whose VALUE is less than or equal to zero or NODATA will belong to the background.

All cells – all cells with valid values belong to the foreground. All cells whose VALUE is NODATA belong to the background.

Cell thinning - Specifies whether or not the foreground cells of the grid will be thinned before vectorization.

Thin foreground cells – If checked the foreground cells will be thinned. This influences the maximum line thickness. NOTE: Do not use this option on a grid with line features that are 3 or less grid cells wide. If unchecked, the tool does not thin foreground cells. This influences the maximum line thickness.

Apply filter – Specifies whether or not a filter will be applied as the first phase of thinning. If checked, the grid will be filtered to smooth the boundaries between foreground and background cells. This option is appropriate only if the Thin foreground cells option has been checked.

Maximum line thickness - The maximum thickness, in map units, of linear features in the input grid. The default thickness is 10 times the  cell size if the Thin foreground cells option is checked, or 2 times the cell size if unchecked. Linear features thicker than the specified Maximum line thickness may be vectorized with more than one arc.

Round junctions – Specifies whether round or sharp turns will be made at turns or junctions. It is also used during the vector conversion process to spline curves or create sharp intersections and corners. If the option is checked, the tool attempts to smooth corners and junctions. This is best for vectorizing natural features such as contours or streams. If this option is unchecked, the tool attempts to preserve rectangular corners and junctions. This is best for vectorizing man-made features such as streets or utility networks.

Set processing tolerances

Dangle length – Minimum length, in map units, of dangling arcs that will be retained. The default is 0.7 times the Maximum line thickness if the Thin foreground cells option is checked, and zero if unchecked.

Weed tolerance – The weed tolerance, in map units, for generalization of arcs. Uses the Douglas-Puecker algorithm for line generalization. The default is 0.0. Values must be greater than or equal to zero. Best results are obtained with a value less than 2.5 times the cell size.

Line attribute to hold grid cell attribute – The name of the item to be created in the AAT of the Output coverage to contain the values of the grid cell item VALUE. If nothing is entered for this option, the grid cell values will be not written to the AAT.


Grid to Point Coverage

Converts a grid representing raster point features to a point coverage. For each cell of the Input grid, a point will be created in the Output coverage. The points will be positioned at the center of the cells they represent. Only Nodata cells will not be transformed into points.

To transfer the grid's cell values to the point coverage, the Grid cell item must be specified.

Notes

The Input grid can have any cell size and any data type. It can have valid cell values as well as Nodata values.

For the grids whose edge columns and rows consist of cells with valid values, the boundaries of the Input grid and the Output coverage will differ by one half of the cell size on each side. The reason is that the Xmin and Ymim values for grids are based on the lower left corner of the lower left cell in the grid, while Xmax and Ymax are determined by the coordinates of the upper right corner of the upper right cell. The Output coverage points are positioned in the centers of the cells which they represent. The BND and tic locations are taken from the outermost points.

Example

Related Topics


Example showing how the boundaries of the input and output are different

Listing of BLUEGRID.BND:

XMIN  = 0.00000
YMIN  = 0.00000
XMAX  = 9.00000
YMAX  = 9.00000

Convert BLUEGRID to a point coverage. The boundary of BLUEPNTCOV.BND is:

XMIN  = 0.50000
YMIN  = 0.50000
XMAX  = 8.50000
YMAX  = 8.50000

Listing of BLUEPNTCOV.TIC:

Record  IDTIC        XTIC       YTIC
     1      1     8.50000    0.50000
     2      4     8.50000    8.50000
     3      2     0.50000    0.50000
     4      3     0.50000    8.50000


The grid you want to convert to a point coverage.


The point coverage you will create.


Enter the name of the item in the Output coverage PAT where the values of the grid cell item VALUE will be stored.


Grid to Polygon Coverage

Converts a grid to a polygon coverage. Arcs are created from cell borders in the grid, and polygons are built from groups of contiguous cells having the same cell values.

Notes

Cells which have a Nodata value in the Input grid will receive the value -9999 in the Output coverage. Therefore, the user should ensure that no cells in the Input grid have the value -9999 unless they should be mapped as Nodata.

Coordinates for the coverage are determined by boundary (BND) and the cell size, both stored as an integral part of the Input grid.

The Output coverage contains four tics located at the map corners, a boundary file, the projection file (PRJ) from the Input grid, and polygons with label points and a polygon attribute table (PAT). The PAT contains an item named GRID-CODE used to store the values of item VALUE from the Input grid value attribute table (VAT).

Special considerations are needed for the conversion of some complex grids, such as image files, which contain many small groups of cells, and a large number of rows and columns (e.g., greater than 500). A complex grid, when converted to coverage polygons, may contain polygons with many interior polygons or donuts. If this degree of detail is not needed then the grid should be smoothed or reclassified before conversion to vector format.

Related Topics


The grid you want to convert to a polygon coverage.


The polygon coverage you will create.


Two vertices on an arc must at least be as far apart as the Weed tolerance to be retained in the coverage you will create. The tool removes vertices that are closer together than the weed tolerance. The resulting arc’s shape is typically more straight. The arc is generalized.

Its unit of measure is that of the Input coverage.

You must use a value equal to or greater than 0. We recommend a value that is smaller than 2.5 times the cell size.


Grid to Tin

The tool creates a tin by including sufficient Input grid cells as to not exceed a specified maximum error between the grid and the tin. The tool is also frequently used to convert a grid derived from a USGS DEM to a tin surface model.

Conversion options

Notes

When the Input grid’s output ZUNITS and ground units are not the same units of measure, the tool will ask if you want to standardize the output units by applying a Z-factor. If you click Yes, the output ZUNITS are converted to ground UNITS For example, if the ground UNITS are in meters and surface ZUNITS are in feet, the output ZUNITS are expressed in meters. If you do not want the Output grid ZUNITS to be standardized, click No when prompted to maintain the default Z-factor of 1.

When a Z-factor other than 1 is given, the output ZUNITS are set to UNKNOWN in the projection file.

The Z-value tolerance is not adjusted by the Z-factor, so the tolerance used should be in the ZUNITS of the Input grid.

Boundaries around internal Nodata mesh points are not included in the Output tin. Triangles will be formed across these regions, permitting interpolation to be performed in these areas.

 The number of points selected by the tool is a function of the specified Z-value tolerance and the smoothness of the Input grid. If a small Z value tolerance is specified or the lattice surface is irregular, more points will be required to build the tin.

A Z-value tolerance near zero usually results in some Input grid cells not being selected. Points with the Nodata value or in regions of constant slope are not required to create the tin.

The tool incrementally improves the tin surface until it meets the specified Z-value tolerance error criterion. First it generates a candidate tin surface using sufficient Input grid cells to fully cover the perimeter of the lattice surface. Once the candidate tin surface is generated, the tool compares the two surfaces at each mesh point to see how well they compare to the Z-value tolerance. Those triangles in the candidate tin that do not meet the error criterion are identified.

If any triangle in the candidate tin does not meet the specified tolerance, the tool selects additional significant mesh points to be inserted into the tin. This procedure is repeated until all triangles in the tin meet the Z-value tolerance error criterion.

Related Topics


The grid you want to convert to a tin.


Indicates the maximum acceptable difference between a point’s z-value in the grid and in the tin. It is a measure of how accurately the tin surface replicates the grid surface.

The tool automatically uses the result of: (zmax – zmin) / 100. Its unit of measure is that of the Input grid. Choose a value greater than 0 that suits your needs.


The maximum number of points allowed in the newly created tin. This places a limit on processing time and the size of the output data model.

NOTE: The Z-value tolerance is not achieved if processing stops because the Max. number of tin points has been reached. By default, as many points are added to the tin as needed to achieve the Z-value tolerance.


The Z-factor states how many ground units in your grid equal one elevation- or z-unit. The tool checks the units of the Input grid; if they are different, the tool asks if you want to standardize them by applying a Z-factor. If you answer Yes, a Z-factor is entered for you. For example, if surface units are feet and ground units are meters, the Z-factor 3.281 is applied to convert feet to meters. A factor of 0.3048 is used to convert meters to feet.

The grid’s elevation units are multiplied by the Z-factor and the result is applied to the tin’s elevation units. The grid data remains unchanged.


The tin you will create.


Conversion options

Z-value tolerance – the maximum allowable error in the z-value of each grid cell and its corresponding location in the Output tin. It is a measure of how accurately the tin surface follows the original grid. The specified Z-value tolerance must be greater than 0. The default Z-value tolerance is (zmax – zmin) / 100.

Max. number of tin points – the maximum number of points allowed in the Output tin. This places a limit on processing time and the size of the output data model.

NOTE: The Z-value tolerance is not achieved if processing stops because the Max. number of tin points has been reached. By default, as many points are added to the tin as needed to achieve the Z-value tolerance.

Z-factor – number of ground x,y UNITS in 1 surface ZUNIT. The input ZUNITS are multiplied by the specified Z-factor to adjust the Output tin’s ZUNITS to another unit of measure. By default, no Z-factor is applied.


The available commands for the current file type. Click a subcommand to view its definition in the definition window on the right. Double-click the subcommand to add it to the file content window below. Edit the content window to add the subcommand’s argument(s), as needed.


The definition of the command selected in the command list. Review the command’s arguments and add the necessary information to the File contents box below.


The Command arguments, along with the selected command, are added to the file contents below when the Add button is clicked or when you press enter. Ensure all required arguments for the selected command are entered and your spelling is correct. No validation of the input is made.


Click to add the contents of the Command arguments box to the file.


The contents will be written to an output file. Use keyboard shortcuts to edit the file, such as Ctrl-C to copy, Ctrl-X to cut and Ctrl-V to paste sections of selected text. Use the Save button on the right to save the contents to a new header/control file.


Opens a browser to save the contents of the file list to a new file.


Moves the selected entry in the file list up.


Moves the selected entry in the file list down.


Deletes the currently selected entry in the file list.


Closes the Header and Control File Builder and places the saved file in the tool option.


Identity

Creates a new coverage by overlaying the polygons of the Identity coverage with the point, line or polygon features of the Input coverage. All features in the Input coverage and only the overlapping features in the Identity coverage are copied to the Output coverage. Attributes from both coverages are copied to the output.

Feature classes

Poly – splits the Input coverage arcs where they overlap the Identity coverage and builds them into a new polygon coverage with label points. Its User-IDs are set to the polygon internal number minus 1.

Region subclasses in either coverage are maintained in the Output coverage. Subclasses with identical names and attribute schemas are appended.

Line – splits the Input coverage arcs where they overlap the Identity coverage and builds them into a new line coverage. Each arc's LPOLY and RPOLY values are set to the internal number of the Identity coverage polygon to its left and right side.

Point – transfers the attributes of the Identity coverage polygon to each point that falls within it.

Join feature attribute tables

When checked, all items from both coverages are copied to the Output coverage. When there are duplicate items, only the Input coverage item will be copied. To see an example, click [image].

When unchecked, only the internal numbers (<cover>#) from both coverages are copied to the Output coverage, saving disk space. Use the relate environment if you need to access attributes in the input coverages. To see an example, click [image].

Notes

The Input coverage, Identity coverage and Output coverage must have different names, even when in different workspaces.

Data model content inherited by the output

How the default fuzzy tolerance is calculated

Processing planar graphs

Related Topics


Join all attributes


Join only internal numbers


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Feature classes

Feature attribute table items

User-IDs (when Join feature attribute tables is checked)

Tics

Annotation

Node attribute table (with feature class Line)

Projection file

Route-systems


The coverage you will overlay with the Identity coverage to combine their features. All features of the Input coverage are preserved in the Output coverage.


Choose the feature class from the Input coverage that you want to overlay and preserve in the Output coverage.

Poly – overlays polygons with polygons

Line – overlays lines with polygons

Point – overlays points with polygons


The polygon coverage you will overlay with the Input coverage.


Choose whether you want to Join feature attribute tables.

Checked – the tool transfers the attributes from the specified feature classes of both coverages to the Output coverage.

Unchecked – the tool transfers only the <cover># from both coverages.to the Output coverage.


The coverage you will create.


IGDS to Coverage Wizard

Converts an Interactive Graphics Design Software (IGDS) file into a coverage.

Notes

Working units are calculated from units of resolution using the working unit parameters contained in the design file header. Working units are real world units such as meters or feet. The sub-units defined for the working unit’s master units define the resolution of the design file. For example, the master units may be meters and the sub-units may be centimeters.

If you extract cells from a design file into a coverage and you plan to convert the coverage back into a design file using the Coverage to IGDS Wizard, it is best to place cells as points.

If you plan to use the Coverage to IGDS Wizard to convert the coverage back to a design file, be sure to read the Coverage to IGDS Wizard help on each panel before using the IGDS to Coverage Wizard. There are a number of issues regarding how attribute linkages are passed to a IGDS file and how the original source file is used.

Supported file extension

Related Topics


Level options

Levels - Select the level you wish to convert. A level is similar to a map layer. Each level can be different or they may be used together. You may convert one or more levels each time you run this wizard. Once you select a level, choose the combination of attributes you wish to convert using the adjacent lists.

Layer name - Character string describing the level. This is an arbitrary name that does not appear in the IGDS file. The name you choose cannot have more than 16 characters and must not contain any blanks. The layer name will be placed in the IGDS-LAYER item in the associated ACODE INFO file.

Element types - The elements present in the selected level.

  List of supported IGDS elements

  List of unsupported IGDS elements

Colors - The unique color values of the element type you have chosen for the currently selected level.

Line styles - The unique line style values of the element type you have chosen for the currently selected level.

Line weights - The unique line weight values of the element type you have chosen for the currently selected level.


Attribute linkages

You have the choice of creating INFO tables that contain attribute information and/or creating an Alink file that maintains the linkages in a binary format.

  Creating INFO attribute tables

  The Alink file


Join the ACODE file to associated feature attribute tables

In addition to positional information, each IGDS element contains information on symbology, attributes and other properties. This information is stored in an INFO file named <Output coverage>.ACODE. Using the <cover>-ID item, the file can be joined to the coverage’s AAT or PAT file and used for analysis if you choose this option. One record is created in the ACODE file for every arc/point/text placed.

  Example of an ACODE file generated using all possible options.

Set the width of the IGDS-Text item

If you are converting text entities, you may specify the width of the IGDS-Text item (1 to 255). The default is 12.


Supported IGDS elements

Only these types of IGDS elements can be translated into an ArcInfo coverage.

Type	Description

2	Cell - a complex element defining a group of elements that describe a symbol. Cells may either be placed as points positioned at the origin of the cell (its ‘true’ location), or as the actual symbol described by its components. Each cell has a six-character name that is stored in the IGDS-TEXT item in the ACODE file.

3	Line - a two-vertex line or point. Lines are placed as two-vertex arcs. Lines with the same beginning and ending vertices will be converted to points.

4	Linestring - a multivertex Line. Line strings are placed as multivertex arcs. The maximum number of vertices an IGDS line string can have is 101.

6	Shape - a closed multivertex polygon. Shapes are placed as multivertex arcs with identical starting and ending vertices.

7	Text Node - a complex element defining a group of text elements having common characteristics, such as a paragraph, where each line is a text element. Text node components are placed as independent text elements sharing a complex element ID in the IGDS-CPXID item in the ACODE file.

11	Curve - A parametric spline curve defined by a set of vertices and a cubic interpolation polynomial. Curves are treated like line strings, and the interpolation between vertices is ignored.

12	Complex String - a complex element defining a group of connected linear elements (line, line string, curve and arc). Complex string components are placed as independent elements sharing a common element ID in the IGDS-CPXID item in the ACODE file.

14	Complex Shape - a complex element defining a group of connected linear elements (line, line string, curve and arc) that form a closed polygon. Complex shape components are placed as independent elements sharing a common element ID in the IGDS-CPXID item in the ACODE file.

15	Ellipse - an ellipse with an arbitrary primary and secondary axis of rotation. Ellipses are placed as 361 vertex arcs with identical starting and ending vertices.

16	Arc - an arbitrary section of an arbitrary ellipse. Arcs are stroked and placed as ArcInfo arcs. The number of vertices per degree of sweep varies with the amount of sweep to take care of arcs with extremely large radii. If the sweep angle is greater than 30 degrees, 1 vertex per degree is stroked. If the sweep angle is between 11 and 30 degrees, 5 vertices per degree are stroked. If the sweep angle is less than 11 degrees, 10 vertices per degree are stroked.

17	Text - up to 255 characters of text. Text may either be placed as points positioned at the text origin (its ‘true’ location), or as annotation with the lower-left-hand corner at the text origin. Annotation rotation, spacing and height are based on values in the text element. The first 12 characters of text are stored in the IGDS-TEXT item in the ACODE file. Enter data fields are ignored. Text will be converted to annotation features by default.


Unsupported IGDS elements

The following types of IGDS elements are ignored if they are encountered in a design file and are not translated into ArcInfo. Any element types not listed here are unknown and also ignored.

Type	Description

1	Cell Library Header

8	Digitizer Setup Data

9	Design File Header

10	Level Symbology

13	Conic

18	Surface (complex)

19	Solid (complex)

22	String

23	Circular Truncated Cone

24	B-Spline Surface (complex)

25	B-Spline Surface Boundary

26	B-Spline Knot Element

27	B-Spline Curve (complex)

28	B-Spline Weight Factor

66	MicroStation Application

87	Raster Header

88	Raster Component


Input IGDS file

Specify the name of the IGDS file to be translated. An IGDS file may also be called a “design” file, so the extension .dgn is often, but not always, used.

The wizard is unable to determine if a design file is 2 or 3 dimensional. If you are unsure, open the file in Microstation and see if you can export the file to a 2D or 3D design file. This will tell you the current setting.

Note: If the translation takes a long time to complete and the coordinates of the second and subsequent points of translated arcs are wrong, then the IGDS file is probably 3D.


The ACODE file

Here are the IGDS items found in the file:

COLUMN  ITEM NAME  WIDTH  OUTPUT  TYPE
 1      COVER-ID      4     5      B
 5      IGDS-LAYER   16     16     C
21      IGDS-TYPE     3     3      I
24      IGDS-LEVEL    2     2      I
26      IGDS-GGNO     5     5      I
31      IGDS-CLASS    1     1      I
32      IGDS-PROPS    8     8      C
40      IGDS-COLOR    3     3      I
43      IGDS-STYLE    1     1      I
44      IGDS-WEIGHT   2     2      I
46      IGDS-TEXT    16    16      C
70      IGDS-ATTPTR   4    11      B
74      IGDS-ZVALUE   8    10      F
82      IGDS-CPXID    4     5      B
86      IGDS-CPXTYPE  3     3      I
89      IGDS-OFFSET   6     7      I

COVER-ID - unique identifier for each feature.

IGDS-LAYER - an arbitrary name given to a level,   or a group or subset of levels meeting certain extraction criteria. The text string “DEFAULT” will be stored if no layer name is given.

IGDS-TYPE - element type (1 to 127).

IGDS-LEVEL - element level (1 to 63). This level value also is the annotation level value which can be used with the ARCPLOT ANNOTEXT command.

IGDS-GGNO - graphic group number of the element. A value of 0 means the element does not belong to a graphic group.

IGDS-CLASS - element class. Possible values are:

0 - Primary
1 - Pattern component
2 - Construction element
3 - Dimension element
4 - Primary rule element
5 - Linear patterned element
6 - Construction rule element

IGDS-PROPS - properties flags stored as a string of 8 characters where each character may be a ‘1’ or a ‘0’. From the left (character index 1), the flags are:

1 - Hole/solid
2 - Non-snappable
3 - Planar
4 - View independent
5 - Attributes present
6 - Modified
7 - New
8 - Locked

IGDS-COLOR - element color (0 to 255).

IGDS-STYLE - element line style (0 to 7).

IGDS-WEIGHT - element line weight (0 to 31).

IGDS-TEXT - type-dependent character data. If the element is a cell, this item contains the cell name. If the element is a text element, this item contains the first 12 characters of text. The Text width option can be used to increase the width of IGDS-TEXT.

IGDS-ATTPTR (FILE or ATTBOTH options only) - pointer to the attribute linkage data in the Alink file. This is a 16-bit word offset.

IGDS-ZVALUE (with 3D files only) - z value of the first point in the element.

IGDS-CPXID - complex element ID. All components of a single complex element will share a common complex element ID. Noncomplex components will have an element ID of zero.

IGDS-CPXTYPE - complex element type of complex element owning this element. Noncomplex elements will have an element type of zero.

IGDS-OFFSET - this value is the starting word number of the element.  In other words, it marks each element’s position in the design file. Each value must be unique. The SOURCE option with the ARCIGDS command uses this item.


Creating INFO attribute tables

The IGDS To Coverage Wizard preserves all levels of all types of attribute linkages. There are three types or families of attribute linkages that can exist in an IGDS file.

1. The earlier IGDS DMRS linkages, still valid in Microstation, are one family.

2. The standard database packages RIS, Informix, Oracle and dBASE, make up another linkage family. Both have standard formats but each type stores different information about the links.

3. The third family, User data linkages, are User defined. There is no set format for User data linkages. The information is stored in multiples of four word blocks. The number of and content of the blocks varies from application to application and must be known to the user than if these linkages are to be used to link to existing attribute data.

It is possible to have multiple linkages for a single feature. A line element may have one DMRS linkages and two User data linkages. Any element may have up to a total of five attribute linkages.

To preserve all attribute linkage types, the IGDS To Coverage Wizard generates three separate linkage tables, one for each linkage type. Coverage features are linked to these files by <cover>-ID number. A single feature may have one or more records in one or more INFO tables. This means there may be a one to many relationship between features and the linkages for that feature.

It may be necessary to use ArcInfo CURSORS to step through multiple records in the relate tables. See Design file attributes in the concepts section for alternative ways of accessing attribute data using the database linkage information in the STDDB file.

Item listing of ATTS.ACODE:

COLUMN   ITEM NAME       WIDTH  OUTPUT  TYPE  N.DEC
 1       COVER-ID          4      5      B     -
 5       IGDS-LAYER       16     16      C     -
21       IGDS-TYPE         3      3      I     -
24       IGDS-LEVEL        2      2      I     -
26       IGDS-GGNO         5      5      I     -
31       IGDS-CLASS        1      1      I     -
32       IGDS-PROPS        8      8      C     -
40       IGDS-COLOR        3      3      I     -
43       IGDS-STYLE        1      1      I     -
44       IGDS-WEIGHT       2      2      I     -
46       IGDS-TEXT        12     12      C     -
58       IGDS-FONT         5      5      I     -
63       IGDS-CPXID        4      5      B     -
67       IGDS-CPXTYPE      3      3      I     -
70       IGDS-OFFSET       4      7      B     -

Item listing of COVER.DMRS:

COLUMN   ITEM NAME      WIDTH  OUTPUT  TYPE  N.DEC
 1       COVER-ID          4      5     B     -
 5       HEADER            4      4     C     -
 9       ENTITY            2      6     B     -
11       OCCUR             4     11     B     -

Item listing of COVER.STDB:

COLUMN   ITEM NAME        WIDTH  OUTPUT  TYPE  N.DEC
 1       COVER-ID             4      5     B     -
 5       HEADER               4      4     C     -
 9       PRIMARY-ID           2      6     B     -
11       SECONDARY-ID         2      6     B     -
13       ENTITY               2      6     B     -
15       MSLINK               4     11     B     -

Item listing of COVER.USER:

COLUMN   ITEM NAME        WIDTH  OUTPUT  TYPE  N.DEC
 1       COVER-ID             4      5     B     -
 5       LINK-ID              2      5     B     -
 7       FOUR_WDBLK          20     20     C     -
**  REDEFINED ITEMS  **
 7       WORD1                4      4     C     -
12       WORD2                4      4     C     -
17       WORD3                4      4     C     -
22       WORD4                4      4     C     -

To use these linkages, you must convert or copy the data out of dBASE III, DMRS, etc., and put the data into a supported DBMS. Then you must set up relates to that data.

Note: If you plan to use the Coverage To IGDS Wizard to convert your coverage back into IGDS format and you plan to keep the attribute linkages, be sure to update information for newly added features in both ACODE and STDDB files. The Coverage To IGDS Wizard will extract attribute linkages from the <cover>.alink file first if it exists, then from any or all of the linkage tables. If you want your attribute linkages to be read from the linkage tables, delete your <cover>.alink system file.


The Alink file

The Alink file is a binary file that contains all attribute linkages. The ACODE file will have an item called IGDS-ATTPTR which will contain a pointer to the location in the Alink file containing the data for each element. The pointer is a 16-bit word offset. The first 16-bit word is an integer specifying the number of 16-bit words to follow of attribute linkage data for that element. The linkages will not be written out to INFO tables with this option.

To use this Alink file, you must write a program to extract the information.


Cells

A cell is a complex element defining a group of elements that describe a symbol. Cells may either be placed as points positioned at the origin of the cell (its ‘true’ location), or as the actual symbol described by its components. Each cell has a six-character name that is stored in the IGDS-TEXT item in the ACODE file.

When you are specifically converting the cells in a level, you may choose which cell definition is converted. The drop down list gives all of the cell definitions used in the selected level.


Image to Grid

Converts an image into a grid or set of grids. Valid image formats are BIL, BIP, BMP, BSQ, CADRG, CIB, ERDAS, GRASS, IMAGINE, JFIF, NITF, RLC, Sun Raster file and TIFF.

Notes

If the Input image is a pseudocolor image, its colormap will be written to the Output colormap. If there is no colormap in the Input image, or no output colormap file name is specified, then no colormap information will be read from the image. The colormap is not part of the grid, but is a separate output.

If the Input image is a multiband image, then an image band can be chosen. If All is chosen, a grid is created for each band in the input image, resulting in an output grid stack. A stack is a set of grids referenced by an INFO table.

The maximum number of characters for an output stack name is 9.

If the Input image has no georeferencing information, then the cell size of the Output grid will be 1.0, and the center of the lower-left cell of the grid will have the coordinates (0.0, 0.0). The BND of the grid will be (-0.5, -0.5, NCOLS-0.5, NROWS-0.5).

If the input image contains georeferencing information in an accompanying world file or stored in the image header, then the image-to-map transformation will be used in creating the grid. If the image-to-map transformation involves nonuniform scaling in the x and y directions or rotation, then the image will be rectified prior to its conversion into a grid, using the specified resampling method. The default resampling option for this rectification is nearest neighbor. The grid will contain square cells.

If the input image is a GRASS cell map, the GRASS category information will be transferred to the output grid VAT into an item called CATEGORY.

TIFF images have a field (Photometric Interpretation field) that causes an image to be inverted when displayed. This display information is not maintained when the image is converted to a grid.

A VAT file will not be created for the output grid if the input is a binary image (containing only the values 0 and 1, as in a scanned line drawing). An STA file will be created, but it will contain the value 0 for the mean and -1 for the standard deviation, indicating that no true statistics have been calculated for the grid. Use the GRID BUILDVAT and BUILDSTA commands to build a VAT and STA file if they are needed.

Image names are case sensitive and are recognized by ArcInfo in this way.

Related Topics


The Input image can be a BIL, BIP, BMP, BSQ, CADRG, CIB, ERDAS, GRASS, IMAGINE, JFIF, NITF, RLC, Sun Raster file or TIFF image.


The Band option is the image band number you want to convert. The default is to convert all bands in the image resulting in a grid stack.


The algorithm to be used when resampling the grid. This will occur if the input image requires rectification.

Nearest neighbor - Calculates the value of each output cell by assigning it the value of the nearest pixel in the Input image.

Bilinear interpolation- Calculates the value of each output cell by interpolating from the values of the four nearest pixels in the Input image based upon the weighted distance to these pixels.

Cubic convolution- Calculates the value of each output cell using the values of the 16 nearest pixels in the Input image to fit a smooth curve through the output cell center.


This optimizes the internal format of the grid for use with either Grid or ArcScan, resulting in improved performance.


The name of the output ASCII colormap file.


The grid or grid stack you will create. The maximum number of characters for an output stack name is 9.


Import from Interchange File

Converts an ArcInfo export interchange file. An interchange file can be used to transport coverages, INFO tables, text files such as AML macros, and other ArcInfo files between various machine types. It contains all coverage information and appropriate INFO table information in a fixed-length ASCII format.

Notes

The tool can read any interchange file, including ones that have been fully or partially compressed.

The data type of the interchange file is determined automatically.

If the interchange file was made with the Arc EXPORT command using the Stack option, the stack directory will be recreated without any of its associated grids. If the interchange file was made with the Stackall option then both the stack directory and the grids associated with that stack are recreated. Only the grids that do not presently exist in the workspace will be recreated.

This tool and the Export to Interchange File tool can be used to back up individual coverages to tape for archiving (as opposed to backing up entire user workspaces). For example, coverages corresponding to map library layers within a single tile (i.e., map sections) can be archived to tape and restored to disk only as they are needed.

If multiple volumes are provided by the Export to Interchange File tool, the ASCII interchange file name must be in the format interchange_file.E00 through interchange_file.Enn, where nn is the last volume ID. If only one volume is produced, this file name must have the.E00 extension.

Issues when using different versions of ArcInfo

Related Topics


The interchange file you want to import.


The coverage or other dataset you will create.


INFO to dBASE

Converts an INFO table to a dBASE table.

The Default mapping option

The Define mapping option

Notes

By default, the tool creates dBASE field names using the INFO item names. When an INFO item name contains invalid characters for dBASE field names, such as hyphens (-) and periods (.), those characters are substituted with valid ones. All illegal characters are converted to underscores (_), unless the illegal character is the first letter, in which case it is converted to ‘A’. You may override these default characters and change any other dBASE field characteristics by choosing the Define mapping option.

For INFO item names that are longer than 10 characters, the tool creates dBASE field names truncated to the first 10 characters.

The maximum record length for an INFO table is 4096 bytes; for a dBASE table it is 4000 bytes. When the dBASE limit is exceeded, the table is converted, but the tool issues a warning message after the conversion that the table may be unusable.

The maximum number of fields for a dBASE data file is 255. The tool will convert only the first 255 items if this dBASE limit is exceeded.

Related Topics


The INFO table you want to convert.


The dBASE table you will create.


Choose the data type mapping from INFO items to dBASE fields.

Default mapping - performs the default item-to-field data type definitions.

Define mapping - you explicitly define the definitions of each dBASE field converted from the INFO items.


Default mapping

The data types between INFO and dBASE differ, making it necessary to map INFO item types into the appropriate dBASE field types. The default INFO to dBASE data type conversion is as follows:

ArcInfo item types             DBASE field types
Type  Width  Output  Dec
  C     n       -     -        Character  <expC> (n)
  D     -       -     -        Date  <expD>
  B     2       -     -        Numeric  <expN> (6,0)
  B     4       -     -        Numeric  <expN> (11,0)
  I     n       -     -        Numeric  <expN> (n,0)
  N     n       -     m        Numeric  <expN> (n,m)
  F     -       n     m        Numeric  <expN> (n,m)

With Default mapping, the tool truncates character fields longer than 254 to the first 254 characters and issues a warning message.

When converting to an N type item, the total width will be at least two digits greater than the number of decimal places, as required by dBASE. For example, an INFO item defined as 1,1,I will become 2,N in the output .dbf table. The Define mapping option will not override this.


Choose the item to be converted.


The name of the new dBASE field, which may be up to 10 characters in length.


The field storage and output width of the new dBASE field.


The dBASE field data type.


The number of decimal places for the decimal data types.


The name of the INFO item being converted.


The width of the INFO item being converted.


The type of the INFO item being converted.


The number of decimal places for the INFO item.


Define mapping

The data types between INFO and dBASE differ making it necessary to map INFO item types into the appropriate dBASE field types. The default data type mapping can be overridden by applying the Define mapping option.

You may define the mapping for only the items you want to control. All items that are not specifically defined are converted using the default INFO to dBASE mapping technique.

When converting to an N type item, the total width will be at least two digits greater than the number of decimal places, as required by dBASE. For example, an INFO item defined as 1,1,I will become 2,N in the output .dbf file. The Define mapping option will not override this.


Click to view the item definitions for the Input INFO table.


The record length refers to the number of bytes necessary to store a row of data in a table. You can determine the record length of your INFO table by taking the start column value of the last item in your INFO table and adding its input width.


INFO to DBMS

Converts an INFO table to a DBMS table.

This tool does not support remote processing using a Geoprocessing Server.

Notes

The default item-to-column data type conversion charts for all supported databases outline the default field types created.

By default, the tool creates DBMS column and table names using the INFO item names. When an INFO item name contains characters not valid for DBMS column names, such as hyphens (-) and periods (.), those characters are substituted with valid ones. All illegal characters are converted to underscores (_), unless the illegal character is the first letter, in which case it is converted to ‘A’, or the last character, in which case it is converted to ‘0’. Several DBMS's may do some additional item name filtering.

If the Default mapping option is specified, the tool truncates character fields longer than 256 to the first 256 characters and issues a warning.

The tool converts blank strings in INFO to NULL values in the DBMS.

The tool does not convert redefined items.

Additional information placed in the Table options field is appended to the SQL CREATE TABLE statement submitted to the DBMS. The options vary between DBMS systems. For the ORACLE DBMS this can include the table STORAGE clause. Consult your particular DBMS SQL CREATE TABLE documentation for a full description of additional table creation parameters.

If an INFO item name is a DBMS-reserved word, the table transfer will fail. For example, item names such as SELECT or FROM cannot be converted to DBMS column names. See your DBMS-specific documentation for a list of reserved column names. Use the Define mapping dialog to rename reserved word items when transferring the file to the DBMS.

If an INFO character item contains paths to system files, you can insert these files into a binary large object (BLOB) column in the DBMS table. To do this, use the Define mapping option and define the INFO item containing the path to the system files to be converted to a BLOB column in the DBMS table. This is the inverse of the DBMSINFO command where BLOB data is written to disk files and the INFO item contains the paths to the files. This facility is only available for DBMS systems which support BLOBs.

This tool requires that the Database Integrator (DBI) be installed. DBI is part of core ArcInfo Workstation. If DBI is not installed the tool will produce a “No available databases, contact your DBMS administrator” warning message when this tool is opened.

Supported DBMS

Related Topics


The name of the database to receive the INFO table. The database name cannot exceed sixteen characters.


Additional native mode DBMS table creation parameters


Choose the data type mapping from INFO items to DBMS fields.

Default mapping - performs the default item-to-field data type definitions.

Define mapping - you explicitly define the definitions of each DBMS field converted from the INFO items.


The new name for the DBMS column.


The DBMS column data type. These can be either ArcInfo-generic SQL data types or DBMS-specific data types. The valid data types are listed in the Managing Tabular Data appendix for your DBMS.


Extra parameters to define the DBMS Column type. This string is appended to the particular column in the composed create table statement (e.g., NOT NULL). See your DBMS documentation for the CREATE command for a full listing of column creation options.


The name of the DBMS table to create.


Data types conversion charts are available for:

 CA OpenIngres

 Informix

 Oracle

 Access

 Sql Server

 Sybase


Default CA-OpenIngres column datatypes are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo data types	CA-OpenIngres data types

Type	Width	Output	Dec

B	2	-	SMALLINT

B	4	-	INTEGER

I	n < 5	-	SMALLINT

I	n >= 5	-	INTEGER

N	-	-	FLOAT

F	4	-	FLOAT4

F	8	-	FLOAT

D	-	-	DATE

C	n	-	CHAR (n)

The default INFO column data types derived from the CA-OpenIngres column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

CA-OpenIngres data types	ArcInfo data types

Type	Width	Output	Dec

CHAR (n)	C	n	n

SMALLINT	B	2	5

INTEGER1	B	2	5

INTEGER	B	4	10

FLOAT4	F	4	12	3

FLOAT	F	8	18	5

VARCHAR (n)	C	n	n

MONEY	N	16	16	2

DATE	C	25	25

TABLE_KEY	C	8	8

OBJECT_KEY	C	16	16

TEXT(n)	C	n	n

Cn - C2000	C	n	n


The default INFORMIX column data types are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo data types	INFORMIX data types

Type	Width	Output	Dec

B	2	-	SMALLINT

B	4	-	INTEGER

I	n < 5	-	SMALLINT

I	n >= 5	-	INTEGER

N	N	-	m	DECIMAL (n,m)

F	4	-	SMALLFLOAT

F	8	-	FLOAT

D	-	-	DATE

C	N	-	CHAR (n)

The default INFO column data types derived from the INFORMIX column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

INFORMIX data types	ArcInfo data types

Type	Width	Output	Dec

CHAR (n)	C	n	n

SMALLINT	B	2	5

INTEGER	B	4	10

SMALLFLOAT	F	4	12	3

FLOAT	F	8	18	5

VARCHAR (n)	C	n	n

MONEY (m)	N	m+2	m+2	2

DECIMAL (n,m)	N	n+2	n+2	m

SERIAL	B	4	10

INTERVAL	C	25	25

DATE	C	10	10

TIME*	C	12	12

DATETIME*	C	25	25

INTERVAL	C	1350	1350

TEXT**	C	128	128

BYTE**	C	128	128

* Time precision may vary.

** The character item contains the pathnames to generate system files.


The default ORACLE column data types are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo data types	ORACLE data types

Type	Width	Output	Dec

B	2	-	NUMBER (5)

B	4	-	NUMBER (38)

I	N	-	NUMBER (5)

N	N	-	0	NUMBER (n)

N	N	-	m > 0	NUMBER (n -1,m)

F	4	-	FLOAT (63)

F	8	-	FLOAT (126)

D	-	-	DATE

C	N	-	CHAR (n)

The default INFO column data types derived from the ORACLE column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

ORACLE data types	ArcInfo data types

Type	Width	Output	Dec

CHAR (n)	C	n	n

VARCHAR (n)	C	n	n

VARCHAR2(n)	C	n	n

NUMBER (n) n<=4	B	2	5

NUMBER (n) 4<n<10 or n = 38	B	4	10

NUMBER (n) 9<n<15	N	n+2	n+2	0

NUMBER (n) 14<n<38	F	8

NUMBER (n,m) n<15	N	n+2	n+2	m

NUMBER (n,m) n>14	F	8	18	m

NUMBER	F	8	18	5

FLOAT (n)1<n<64	F	4	12	3

FLOAT (n)63<n<127	F	8	18	5

DATE	C	20	20

LONG*	C	128	128

LONGRAW*	C	128	128

ROWID	C	23	23

MLSLABEL	C	8	8

* The C 128 item contains the path to system files containing the BLOB data.


The default Microsoft Access column data types are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo	Microsoft Access	Microsoft Access

data types	data types	ODBC data types

Type	Width	Out	Dec

B	2	-	NUMBER	SHORT

(fieldsize= INTEGER)

B	4	-	NUMBER	LONG

(fieldsize= LONG INTEGER)

I	n < 5	-	NUMBER	SHORT

(fieldsize= INTEGER)

I	n >= 5	-	NUMBER	LONG

(fieldsize= LONG INTEGER)

N	-	-	-	NUMBER	DOUBLE

(fieldsize= DOUBLE)

F	4	-	-	NUMBER	SINGLE

(fieldsize= SINGLE)

F	8	-	-	NUMBER	DATETIME

(fieldsize= SINGLE)

D	-	-	DATETIME	DOUBLE

C	n	-	CHAR (n)	CHAR(n)

The default INFO column data types derived from the Microsoft Access column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

Microsoft Access	Microsoft Access	ArcInfo

data types	ODBC data types	data types

Type	Width	Output	Dec

BINARY (n)	BINARY	C	n	n

BIT	BIT	B	2	1

CHAR (n)	CHAR (n)	C	n	n

COUNTER	COUNTER	B	4	10

CURRENCY	CURRENCY	N	18	4

DATE/TIME	DATETIME	C	20	20

GUID	BINARY	C	n	n

LONG BINARY	LONGBINARY	C	128	128

LONG TEXT	LONGTEXT	C	128	128

MEMO	LONGTEXT	C	128	128

NUMBER	SINGLE	F	4	10

(fieldsize=SINGLE)

NUMBER	DOUBLE	F	8	18

(fieldsize=DOUBLE)

NUMBER	UNSIGNEDBYTE	B	2	3

(fieldsize=BYTE)

NUMBER	SHORT	B	2	5

(fieldsize=INTEGER)

NUMBER	LONG	B	4	10

(fieldsize=LONG INTEGER)

OLE	LONGBINARY	C	128	128

TEXT (n)	VARCHAR (n)	C	n	n

VARBINARY (n)	VARBINARY (n)	C	n	n

* The C 128 item contains the path to system files containing the BLOB data.


The default Microsoft SQL Server column data types are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo data types	Microsoft SQL Server data types

Type	Width	Output	Dec

B	2	-	SMALLINT

B	4	-	INT

I	n < 5	-	SMALLINT

I	n >= 5	-	INT

N	-	-	-	DECIMAL

F	4	-	-	FLOAT

F	8	-	-	DOUBLE PRECISION

D	-	-	DATETIME

C	n	-	CHAR (n)

The default INFO column data types derived from the Microsoft SQL Server column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

Microsoft SQL Server data types	ArcInfo data types

Type	Width	Output	Dec

CHAR (n)	C	n	n

NCHAR(n)	C	n	n

VARCHAR(n)	C	n	n

NVARCHAR(n)	C	n	n

TEXT*	C	128	128

TINYINT	B	2	5

SMALLINT	B	2	5

INT	B	4	10

FLOAT	F	4	12	3

DOUBLE PRECISION	F	8	18	5

REAL	F	4	12	3

DECIMAL	F	8	18	5

NUMERIC	F	8	18	5

SMALLMONEY	F	4	12	3

MONEY	F	8	18	5

SMALLDATETIME	C	24	24

DATETIME	C	24	24

BIT	C	1	1

BINARY	C	402	402

VARBINARY	C	402	402

IMAGE*	C	128	128

* The C 128 item contains the path to system files containing the BLOB data.


The default SYBASE column data types are derived from the INFO column data types according to the data type conversion chart shown below.

Default INFO to DBMS Data Type Conversion

ArcInfo data types	SYBASE data types

Type	Width	Output	Dec

B	2	-	SMALLINT

B	4	-	INT

I	n < 5	-	SMALLINT

I	n >= 5	-	INT

N	N	-	0	DECIMAL(n,0)

N	n	-	m>0	DECIMAL (n-1, m)

F	4	-	-	REAL

F	8	-	-	DOUBLE PRECISION

D	-	-	DATETIME

C	n	-	CHAR (n)

The default INFO column data types derived from the SYBASE column data types according to the data type conversion chart shown below.

Default DBMS to INFO Data Type Conversion

SYBASE data types	ArcInfo data types

Type	Width	Output	Dec

CHAR (n)	C	n	n

NCHAR(n)	C	n	n

VARCHAR(n)	C	n	n

NVARCHAR(n)	C	n	n

TEXT*	C	128	128

TINYINT	B	2	5

SMALLINT	B	2	5

INT	B	4	10

FLOAT (p)p<16	F	4	12	3

FLOAT(p)p>=16	F	8	18	5

DOUBLE PRECISION	F	8	18	5

REAL	F	4	12	3

DECIMAL / NUMERIC (p,0)p<15	I	p+1	p+1

DECIMAL / NUMERIC (p,0)p>14	F	8	18	0

DECIMAL / NUMERIC (p,s)p<15	N	p+2	p+2	5

DECIMAL / NUMERIC (p,s)p>14	F	8	18	5

SMALLMONEY	F	4	12	3

MONEY	F	8	18	5

SMALLDATETIME	C	24	24

DATETIME	C	26	26

BIT	C	1	1

BINARY	C	402	402

VARBINARY	C	402	402

IMAGE*	C	128	128

* The C 128 item contains the path to system files containing the BLOB data.


Intersect

Creates a new coverage by overlaying the polygons of the Intersect coverage with the point, line or polygon features of the Input coverage. Only the features of the Input coverage that fall within the Intersect coverage polygons are copied to the Output coverage. Attributes from both coverages are copied to the output.

Feature classes

Poly – splits the Input coverage arcs where they overlap the Intersect coverage and builds them into a new polygon coverage with label points. Its User-IDs are set to the polygon internal number minus 1.

Region subclasses in either coverage are maintained in the Output coverage. Subclasses with identical names and attribute schemas are appended.

Line – splits the Input coverage arcs where they overlap the Intersect coverage and builds them into a new line coverage. Each arc's LPOLY and RPOLY values are set to the internal number of the Intersect coverage polygon to its left and right side.

Point – transfers the attributes of the Intersect coverage polygon to each point that falls within it.

Join feature attribute tables

When checked, all items from both coverages are copied to the Output coverage. When there are duplicate items, only the Input coverage item will be copied. To see an example, click [image].

When unchecked, only the internal numbers (<cover>#) from both coverages are copied to the Output coverage, saving disk space. Use the relate environment if you need to access attributes in the coverages. To see an example, click [image].

Notes

The Input coverage, Intersect coverage and Output coverage must have different names, even when in different workspaces.

Data model content inherited by the output

How the default fuzzy tolerance is calculated

Processing planar graphs

Related Topics


Join all attributes


Join only internal numbers


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Feature classes

Feature attribute table items

User-IDs (when Join feature attribute tables is checked)

Tics

Annotation

Node attribute table (with feature class Line)

Projection file

Route-systems


The coverage you will overlay with the Intersect coverage to combine their features.


Choose the feature class from the Input coverage that you want to overlay and preserve in the Output coverage.

Poly – overlays polygons with polygons.

Line – overlays lines with polygons.

Point – overlays points with polygons.


The polygon coverage you will overlay with the Input coverage.


Choose whether you want to Join feature attribute tables.

Checked – the tool transfers the attributes from the specified feature classes of both coverages to the Output coverage.

Unchecked – the tool transfers only the <COVER># from both coverages to the Output coverage.


The coverage you will create.


Standard item-to-field data type mapping

ARC/INFO data types	dBASE data types

Type	Width	Output	Dec	Type	Width	Output + Dec

C	n	-	-	Character	<expC> 	(n)

D 	-	-	-	Date	<expD>

B	2	-	-	Numeric	<expN> 	(6,0)

B	4	-	-	Numeric	<expN> 	(11,0)

I	n	-	-	Numeric	<expN> 	(n,0)

N	n	-	m	Numeric	<expN> 	(n,m)

F	-	n	m	Numeric	<expN> 	(n,m)


Join Tables

Joins the item definitions and values of two tables based on a shared item. A record in the Join table is matched to each record of the Input table when their Relate item values are equal. Then the item values from the two records are copied to the Output table.

The tool provides three Join methods:

Linear – iterates sequentially through the Join table for every record in the Input table to locate an item value that is identical to the specified Relate item. Processing speed is optimized if the Relate item is indexed. To create an item index on the Relate item, access the item from ArcCatalog.

Ordered – uses a binary search for the matching process and requires that the Join table is sorted in ascending order on the Relate item.

Link – requires a Relate item only in the Input table. The Relate item value in each record of the Input table is matched to the record number in the Join table.

Notes

To maintain the integrity of a feature attribute table, do not insert items before the <cover>-ID (when Output table equals Input table.)

It is recommended to use a Relate item of the same definition in the two tables to be joined.

If the same item name is encountered in both tables, the item from the Input table is maintained and the Join table item is not merged.

Items of type integer can be matched with items of type numeric, provided their values are identical. For example, the integer item value 111 will match the numeric value 111.00.

Items of type numeric with a different number of decimal places can be matched, provided their values are identical. For example, the value 987.65 will match with 987.6500.

To avoid loss of information and redundant data storage, ensure that items in the two tables match one-to-one. If this one-to-one correspondence does not exist, one of the following will occur:

If an Input table record matches more than one record in the Join table, only one match is saved to the Output table. The record that is saved may or may not be the first match of the file, depending on whether the item is indexed.

If an Input table record does not match any record in the Join table, the values of the Join table items in the corresponding Output table record are set to zero or left blank.

If a Join table record matches more than one record in the Input table, the Join table record is merged with every matching Input table record.

If a Join table record does not match any record in the Input table, it does not appear in the Output table.

A redefined item can be used as the Relate item in most cases. But when a redefined item contains items of different types and is numeric, its use as the Relate item is not recommended. Such a redefined item can result in illogical or untranslatable numbers.

When a grid’s value attribute table (VAT) has been modified by joining another table, the index on the VALUE item must be recreated. To create an item index, access the item from ArcCatalog.

To maintain the Input table, name the Output table differently.

Related Topics


The table you want to join with a second table.


The table you want to join with the Input table.


The table you will create. If the table already exists, it will be replaced.


Lists items common to both the Input table and the Join table. The list is automatically populated after you have selected the Join table, and includes redefined items.


The Join table items are automatically added after the last Input table item, unless you choose a different Insert after item. To preserve the integrity of a feature attribute table, do not insert the items before the <cover>-ID item if the Output table is the same as the Input table.


Choose the method for joining your tables:

Linear – joins records from both tables that have matching relate item values, and writes those values to the Output table. Use this method if your tables are not sorted.

Ordered – requires that the Join table is sorted in ascending order on the Relate item.

Link – matches the Relate item value in each record of the Input table with a record number in the Join table. Only the Input table requires the Relate item.


Line Coverage to Route

Creates a route system from lines or appends lines to a route system. It groups lines that are topologically connected and that have unique values for the Input item to create the route system. The unique values of Input item are always written to Output item in the route attribute table (RAT); these values help to identify routes once they have been created.

When appending routes to an existing route system, Output item must be the name of an existing item on the RAT of Route system. The tool will append a section to an existing route for every input arc having Input item equal to Output item in the RAT, provided the input arcs are topologically connected to the route being appended to. Measures on the original part of the route being appended to are updated based on the measures assigned to the new sections and the specified Starting node. For those groups of arcs having values for Input item not found in Output item, a new route is created.

Recommended pre-processing

The Input coverage must have an arc attribute table (AAT) and node numbers must exist and be up to date. Use Build with the Line option to create or update the AAT. Use Renumber Nodes to update node numbers.

Notes

Two or more routes are merged if they have the same value for Output item and become connected due to arcs being appended.

The tool automatically includes lines with a Null or zero-valued Input item and builds a separate route system for these. If you uncheck Include lines with Input item values of Null (for character type items, zero for numeric items) these lines are disregarded.

If the Input item is defined as floating point, it is truncated to integer for building the routes in the new route system.

Sections are not appended to an existing route if the route contains overlapping sections. The input arcs are assigned to a new route instead.

Related Topics


The coverage with lines you want to convert or append to a route system. It must have an AAT with unique, sequential node numbers.


The item in the AAT used to group arcs into separate routes. A new route is created in the RAT for each unique value in this item. If no item is used, the tool creates a route for each topologically connected set of arcs.


The name of the new item in the output RAT that will contain the unique values of the Input item. The default is the same name as Input item.; change the name to suit your needs.

When appending routes to an existing route-system, the tool displays existing items in the RAT so you can choose one.


The item in the AAT that will be accumulated to produce the measure values in the section attribute table. The default item displayed is LENGTH. Choose another numeric item to suit your needs.


Determines coordinate priority when choosing a start node for the route.

Upper Left indicates the upper left quadrant.

Upper Right indicates the upper right quadrant.

Lower Left indicates the lower left quadrant.

Lower Right indicates the lower right quadrant.


Upper Left indicates the upper left quadrant as location for the route’s start point.


Upper Right indicates the upper right quadrant as location for the route’s start point.


Lower Left indicates the lower left quadrant as location for the route’s start point.


Lower Right indicates the lower right quadrant as location for the route’s start point.


Choose whether you want to include lines with a value of Null or zero for Input item.

Checked – includes lines with Null or zero values when creating routes.

Unchecked – disregards lines with Null or zero values when creating routes.

A blank is considered to be zero (0.0) or null where Input item is numeric, and null where Input item is character.


The Route system you will create or add to. It is created in the Input coverage. If it already exists in the Input coverage, the tool will display you the RAT attributes in Output item.


Line Coverage to Grid

Converts data associated with line features to grid cell format. Imagine a grid drawn on a map of coverage features:  each cell in the grid is assigned a code according to the arc(s) it overlays. The codes assigned to the cells are determined by the Value item and Lookup table. If a cell has more than one possible code (i.e., it contains two or more arcs), the code of the arc with the greatest length in the cell is used.

It may not be desirable to always assign the code with the largest length to a cell. Small, but important, features could be lost from the grid if cell codes are assigned solely on the basis of area. In this case, a Weight table is used to associate an importance (weight) to a code. Codes with larger weights then take precedence over codes with lower weights. When weights are identical, the code with the largest area in the cell is used. If a code does not have an entry in the weight table, it is assigned a weight of 0.

Notes

The cell resolution should be chosen carefully and with consideration of these factors:

A cell size finer than the input resolution will not produce data at a finer resolution than the input data.

The Output grid cell resolution should be the same as or coarser than the input data.

Disk capacity and desired response time when determining the cell resolution that is best suited for your particular application.

Grid cell values must be in the range of 32-bit integers or floating-point numbers.

The Weight table is not used as a lookup table. It is used to assign weights to grid cell codes. These weights are used to resolve cases when a single cell can have several possible codes. The code with the highest weight will be assigned to the cell.

The projection file (PRJ) of the Input coverage is copied to the Output grid.

Sample lookup table

Sample weight table

Related Topics


The line coverage you want to convert to a grid.


The grid you will create.


Choose the line attribute whose values you want to assign to the grid’s VALUE attribute. The list shows only numeric items. The tool chooses the internal arc number by default.


Assigns a value item code to each grid cell. The table is used together with the Value item you just selected. It contains at least two items: the Value item and CODE. It must be sorted in ascending order on the Value item. CODE must be numeric. This table must already exist. For more information about lookup tables, see Using lookup tables.


Assigns an importance weight to a grid cell in order to preserve a small, yet important feature. The table is used together with the Lookup table. It contains at least two numeric items, CODE and WEIGHT, and is sorted in ascending order on CODE. This table must already exist.


The size of a single grid cell. The value displayed here is automatically calculated for you from the coverage resolution. Change this value to suit your needs.


The number of rows the grid will have. The number displayed is automatically calculated from the cell size and the coverage extent.


The number of columns the grid will have. The number displayed is automatically calculated from the cell size and the coverage extent.


Choose the value you want to assign to cells that do not contain features.

Nodata – assigns the value ‘Nodata’ to a cell whose true value is not known.

Zero – assigns the value 0 to an empty cell.


Sample lookup table

LINEGRID.LUT item definitions

COLUMN  ITEM NAME   WIDTH  OUTPUT  TYPE N.DEC
    1   ATTRIBUTE2      4      5     I     -
    5   CODE            5      5     I     -

LINEGRID.LUT listing of records

Record  ATTRIBUTE2  CODE
     1      1        101
     2      2        102
     3      3        103
     4      4        104
     5      5        105
     6      6        106
     7      7        107
     8      8        108


Sample weight table

LINEGRID_WT item definitions

COLUMN  ITEM NAME   WIDTH  OUTPUT  TYPE N.DEC
    1   CODE            5      5     I     -
    6   WEIGHT          5      5     I     -

LINEGRID_WT listing of records

Record   CODE  WEIGHT
     1    102      1
     2    103      3
     3    104      5
     4    105      9
     5    106      7


Line Coverage to Region

Converts arcs to preliminary regions in a new or existing coverage, or appends preliminary regions to an existing region subclass. Arcs are grouped into preliminary regions based on the unique value of the Line item, and must form closed loops. The unique values are saved in the output subclass Region item.

The tool provides two options to Create regions. To see an example, click [image].

From multiple rings creates a single region feature from many rings of arcs with identical Line item value. For example, if all Hawaiian Islands have the same value for the Line item, they will all become a single region feature.

From single ring creates a region feature from each individual ring of arcs and thus lets you identify any arcs that do not close to form a ring.

The Selection file lets you specify a subset of arcs to group into regions. The tool uses all arcs if you do not enter a Selection file or if the Selection file does not select any arcs.

Required post-processing

To create fully built regions, use the Clean or Build tool with the Poly option. To see an example, click [image].

The tool does not compute the area of the preliminary regions, but sets the AREA values in the PATsubclass to zero and computes the PERIMETER. Using the Build tool with the Poly option will calculate the AREA values.

Notes

The Input coverage must have an arc attribute table (AAT) in order to specify the Line item.

When Line item is not specified, each arc in the Input coverage becomes a preliminary region and should form a closed loop.

The Region item can have the same name as the Line item. If a Region item already exists in the output Subclass polygon attribute table (PAT), the one you specify must have the same item definition.

The tool creates the items RINGS_OK and RINGS_NOK in the PAT<subclass>. The values for RINGS_OK indicate the number of closed loops or rings in the preliminary region; the values for RINGS_NOK indicate the number of unclosed rings.

Arcs can be reused in any grouping in sequential iterations of the tool to append duplicate or overlapping preliminary regions to the same subclass or to different subclasses.

The tool assigns sequential User-IDs to the preliminary regions, beginning with one, and stores them in the PAT<subclas>.

Polygon topology becomes preliminary in the Output coverage when preliminary regions are appended to a subclass, but is rebuilt when you run the Build or Clean tool.

Arcs that are already part of one or more fully structured regions are not available for appending to the Subclass, because they may not form closed rings when grouped.

An empty subclass can be created, and is preserved after running Build or Clean.

Unclosed rings are included in the preliminary regions and will be used in Build and Clean. In some cases, correct regions can result after structuring rings that overshoot, for example.

Related Topics


The coverage whose arcs you want to convert to regions. It must have an AAT.


The coverage that will contain the preliminary regions. It can be the same as the Input coverage, or a new coverage.


The region Subclass you will create or append to, if it exists. The name can be up to 13 characters, and must not begin with a number.


The item whose values you want to use to group arcs into regions. The Line item list is automatically populated from the Input coverage AAT. If it is not specified, each arc in the Input coverage becomes a preliminary region and should form a closed loop.


The item to store the values of the arcs grouped into preliminary regions. The name displayed is the same as the Line item. Rename the Region item to suit your needs. It is stored in the output region PATsubclass.


The Selection file identifies the arcs you want to group into regions. This file is created in ArcPlot and must already exist. A selection file is useful if you want to include the same arc in different groupings.


Choose how to create regions:

From multiple rings creates regions from multiple rings of arcs with identical values for the Line item.

From single ring creates regions from each individual ring of arcs.


The Selection file identifies the arcs you want to group into regions based on one or more attribute/value pairs. This file is created in ArcPlot and must already exist. A selection file is useful if you want to apply multiple queries to the same selected feature class.


Example of Multiple vs Single rings

This line coverage has two rings, each composed of many arcs. The Line item values are the same for every arc.

Multiple

Running Line Coverage to Region with the From multiple rings option creates one region for each group of arcs that have identical Line item values. Here, one region is created from the two rings of arcs. The inner ring defines the inner boundary of the region and the outer ring defines the outer boundary of the region.

Single

The From single ring option creates a region for each ring of arcs. Here, two regions are created from the two rings of arcs. Each ring defines the outer boundary of a region.


Create fully built regions from preliminary regions

Line Coverage to Region structures the arcs into closed rings. The relationship between a region and its boundary arcs is maintained through the region PAL file. The relationship between a region and its polygons is maintained through the RXP (region cross reference) file. The tool constructs the initial region PAL file and creates an empty RXP file. Build or Clean then creates region topology by building the complete RXP file.

After Line Coverage to Region, the cross reference file (RXP) is empty. Now use Build or Clean to structure the regions.

Structuring preliminary regions with Build or Clean replaces duplicate arcs with single arcs and places nodes where two arcs cross.

Preliminary regions on the left are comprised of two arcs that partially overlap. The Build or Clean operation replaces the overlapping arcs with a single arc and creates nodes where two arcs cross. The output coverage will contain five arcs.

A one-to-many arc-region relationship is directly maintained through the region PAL file and indirectly through the region-polygon cross reference file.


MIF to Shapefile

Converts a MapInfo Interchange Format (MIF) file into a shapefile.

The following is a list of possible features found in a MIF file:

Point - Extracts all point features and makes a point shapefile.

Text - Extracts all text features and makes a point shapefile. The tool adds a 255 character field called MIF_TEXT to the shapefile's attribute table which holds the text from the text field.

Line - Extracts all line features and makes a line shapefile. MIF line features include LINE, POLYLINE and ARC.

Poly - Extracts all polygon features and makes a polygon shapefile. MIF REGION, RECTANGLE, ROUNDED RECTANGLE and ELLIPSE features are also written to the polygon shapefile.

Important note

This tool does not support remote processing using a Geoprocessing Server. The tool is always run with a local processing state.

Notes

The tool has the following limitations:

32763 nodes per REGION or LINE

3000 polygons per REGION

Supported file extension


The MIF file you want to convert to a shapefile.


The name of the shapefile you want to create.


The feature class you want to convert from the MIF file.

Point - Extracts all point features and makes a point shapefile.

Text - Extracts all text features and makes a point shapefile. The tool adds a 255 character field called MIF_TEXT to the shapefile's attribute table which holds the text from the text field.

Line - Extracts all line features and makes a line shapefile. MIF line features include LINE, POLYLINE and ARC.

Poly - Extracts all polygon features and makes a polygon shapefile. MIF REGION, RECTANGLE, ROUNDED RECTANGLE and ELLIPSE features are also written to the polygon shapefile.


MOSS To Coverage

Converts a file in MOSS export format into an ArcInfo coverage. MOSS export files contain polygon data extracted from the U.S. Department of Interior’s MOSS public domain GIS. These consist of points, lines, or closed polygon loops (possibly with islands), and a 30-character attribute field referred to as the subject value.

Sample MOSS export file

Notes

Care must be used in selecting the proper Coverage type option because a MOSS export file does not explicitly identify the feature type it contains. A wrong feature type specification in the tool will produce incorrect results. For example, if you have a MOSS export file of polygons yet specify the feature class as Line, the resulting coverage will have a spike for every island found inside a complex polygon.

Since MOSS uses closed-loop polygons, all coverage arcs will initially be created as closed loops. To create arc-node and polygon topology, the Clean tool must be used.

When the Coverage type is Poly, the new coverage will have a polygon attribute table (PAT) containing the subject values in a character item named DATA. The coverage will require further processing using the Build or Clean tools in order to create polygon topology.

The coverage created by the tool with the Coverage type set to Line,will have arcs, an arc attribute table (AAT) containing the attribute values (in a C30 item), and four tics. You may wish to use the Clean tool with the Feature class set to Line to split intersecting arcs.

The coverage created by the tool with the Coverage type set to Point, will have label points, a point attribute table (PAT) containing the attribute values (in a C30 item), and four tics.

If the MOSS map file was not digitized in AMS or WAMS, it may be necessary to use the Clean tool to process duplicate arcs. You may need to use the Eliminate tool to remove sliver polygons after removing these arcs.

Supported file extension

Related Topics


Sample MOSS export file

Here is a partial listing of a MOSS export file.

1           EAST 2ND                              2
            543702.63  638368.25
            543409.13  638369.00
2           EAST 2ND                              2
            547752.25  638261.63
            548558.63  638266.13
3           EAST 3RD                             11
            543768.00  638025.88
            543825.50  638037.88
            543906.00  638045.00
            543970.50  638047.63
            543970.50  638047.63
            544000.50  638046.13
            544028.00  638040.25
            544055.50  638029.25
            544080.00  638014.38
            544092.50  637999.38
            544200.63  637900.00
4           EAST 3RD                              2
            548560.38  638006.75
            547750.25  638010.13
5           EAST 3RD                              2
            548813.75  638046.25
            548994.00  638046.00
6           EAST 3RD                              2
            548994.00  638046.00
            549069.00  638046.00


The MOSS file you want to convert to a coverage.


The coverage you will create.


Choose the type of coverage you want to create.

Poly – creates a polygon coverage. Use the Build or Clean tool to create polygon topology.

Line – creates a line coverage. Use the Clean tool to split intersecting arcs.

Point – creates a point coverage.


Creates a polygon coverage. Run the Build or Clean tool to create polygon topology.


Creates a line coverage. Run the Clean tool to split intersecting arcs.


Creates a point coverage.


Near

Computes the distance from every Input coverage point to the nearest Near coverage point, line or node within the maximum Search radius.

The results are recorded in the Output coverage point attribute table. Items for DISTANCE and the internal number of the closest feature are added or updated; items for x and y coordinates are added when Record x,y coordinates of nearest feature is checked. All item values are set to 0 if no feature is found within the Search radius.

Notes

DISTANCE values are recalculated if this item already exists in the Input coverage. If the DISTANCE item is added, it will be in the same precision as the coverage.

Output item definitions

Graphic of distance calculations

Common uses for Near include:

Assigning point attributes to nearest arcs or vice versa

Assigning address ranges to arcs

Associating point attributes to nodes such as DIME node numbers

Finding the nearest available line in a network

Related Topics


The Search radius is the maximum distance in coverage units a feature can be from the current point for consideration as the closest feature. The default is the width or height of the Near coverage BND divided by 100, whichever is larger.


Graphic of distance calculations


Output item definitions

 Items written or updated in the Output coverage point attribute table, when saving the x,y coordinates:

ITEM NAME         WIDTH  OUTPUT  TYPE  N.DEC
<Near coverage>#      4      5     B       -
DISTANCE              4     12     F       3
X-COORD               4     12     F       3
Y-COORD               4     12     F       3

If the Input coverage is double precision, the output items will also be double precision:

ITEM NAME         WIDTH  OUTPUT  TYPE  N.DEC
<Near coverage>#      4      5     B       -
DISTANCE              8     18     F       5
X-COORD               8     18     F       5
Y-COORD               8     18     F       5


The coverage with points from which distances are calculated to the closest Near coverage features.


The line or point coverage whose features are used to calculate distances from each Input coverage point.


Choose the feature class to locate:

Line – the nearest location along any arc

Point – the nearest point

Node – the nearest node on any arc


The maximum distance a point can be from another feature for the calculation to take place. The default is the width or height of the Near coverage BND divided by 100, whichever is larger.


When checked, the x,y coordinates of the nearest feature are written to the Output coverage PAT.


The point coverage that will contain the distance calculation results. This can be the Input coverage, or a new coverage.


OLE DB to Table

Converts an Ole DB table to an dBASE or INFO table.

Related Topics


The Ole DB table you want to convert.


Choose an Output table type:

dBASE creates a dBASE table.

INFO creates an INFO table. NOTE: This table must be placed into an INFO directory.


The table you will create; it will be the type selected in Output table type.


Overlay Wizard

Overlay operations create a new coverage by computing the geometric intersection of two coverages - an input coverage and an overlay coverage.

The Input coverage can be a point, line, or polygon coverage.

The Overlay coverage is always a polygon coverage.

The Output coverage has rebuilt topology and inherits attributes from both coverages. It also inherits from the Input coverage:

Feature classes

Feature attribute table items

User-IDs (if you choose to Keep all attributes from both coverages)

Tics

Annotation

Node attribute table

Projection file

Route-systems

Differences between the three operations:

Union

The Input coverage is always a polygon coverage.

All features from both coverages are maintained.

Identity

The Input coverage can have polygons, lines or points.

All Input coverage features, and the Overlay coverage features that overlap the Input coverage, are maintained.

Intersect

The Input coverage can have polygons, lines or points.

Only Input coverage features and Overlay coverage features that overlap are maintained.

Related Topics


Feature classes

The wizard discovers the feature classes in the Input coverage, and offers those available for overlay.

Poly

Input coverage arcs are split at their intersections with Overlay coverage polygons. The resulting arcs are used to build polygons.

Label points are generated for each Output coverage polygon. The new polygon User-IDs are set equal to the polygon internal number minus 1.

Region subclasses from both Input coverage and Overlay coverage are maintained and clipped by the extent of the output coverage. Subclasses with identical names and attribute schemas are appended.

Line

Overlay coverage arcs are used to split Input coverage arcs where they overlap. The LPOLY and RPOLY values are set to the internal numbers of the Overlay coverage polygons to each arc’s left and right sides.

Point

The Output coverage PAT lists the Overlay coverage polygon that each point falls within.


Join attributes

Keep all attributes from both coverages

All items from both coverages will appear in the Output coverage feature attribute table.

If a duplicate item is encountered, the item in the Input coverage will be maintained and the one in the Overlay coverage will be dropped.

Example

Keep only the internal ID from each coverage

Only the feature’s internal number (<COVER>#) from the Input coverage and the Overlay coverage will be joined into the Output coverage feature attribute table.

This option is useful in reducing the size of the Output coverage feature attribute table. The relate environment is then used to relate to other tables containing the attributes of Output coverage features.

Example


Fuzzy tolerance

Fuzzy tolerance is the minimum distance between coordinates in the Output coverage. The tool calculates the minimum Fuzzy tolerance from the Input and Overlay coverages. Its unit of measure is that of the Input coverage’s. The default is determined in this order:

1	Tolerance values are read from the existing coverage TOL file.

2	If no TOL file exists and the width of the BND is between 1 and 100, the tolerance is 0.002.

3	Otherwise, the tolerance is 1/10,000 of the width or height of the BND, whichever is greater.

How to determine a fuzzy tolerance


Keep all attributes from both coverages


Keep only the internal ID from each coverages


Point Coverage to Grid

Converts data associated with point features to grid cell format. Imagine a grid drawn on a map of coverage features:  each cell in the grid is assigned a code according to the point(s) it overlays. The codes assigned to the cells are determined by the Value item and Lookup table. If a cell has more than one possible code (i.e., it contains two or more points), and a Value item has been specified, the code with the most occurrences in the cell is used. If no Value item has been specified and there are multiple points within the cell, the assignment is based upon the scanning order and is not easily predictable.

It may not be desirable to always assign the code with the most occurrences to a cell. For example, less frequent but important features could be lost from the grid if cell codes are assigned solely on the basis of occurrence. In this case, a Weight table is used to associate an importance (weight) to a code. Codes with larger weights then take precedence over codes with lower weights. When weights are identical, the code with the most occurrences in the cell is used. If a code does not have an entry in the weight table, it is assigned a weight of 0.

Notes

The cell resolution should be chosen carefully and with consideration of these factors:

A cell size finer than the input resolution will not produce data at a finer resolution than the input data.

The Output grid cell resolution should be the same as or coarser than the input data.

Disk capacity and desired response time when determining the cell resolution that is best suited for your particular application.

Grid cell values must be in the range of 32-bit integers or floating-point numbers.

An Output grid value attribute table (VAT) table is created for resultant integer grids. The VAT will have items VALUE and COUNT. VALUE contains the number assigned to the cells in the Output grid, and COUNT is the number of cells in the Output grid that were assigned that cell value.

The projection file (PRJ) of the Input coverage is copied to the Output grid.

The Weight table is not used as a lookup table. It is used to assign weights to grid cell codes. These weights are used to resolve cases when a single cell can have several possible codes. In this case, the code with the highest weight will be assigned to the cell.

If no points fall within a cell, it is assigned Nodata.

Sample lookup table

Sample weight table

Related Topics


The point coverage you want to convert to a grid.


Choose the point attribute whose values you want to assign to the grid’s VALUE item. The list shows only numeric items. The tool chooses the internal point number by default.


Sample lookup table

POINTGRID.LUT item definitions

 COLUMN  ITEM NAME     WIDTH  OUTPUT  TYPE N.DEC
    1    ATTRIBUTE2     4     5         I
    5    CODE           5     5         I

POINTGRID.LUT listing of records

Record  ATTRIBUTE2  CODE
     1      1        101
     2      2        102
     3      3        103
     4      4        104
     5      5        105
     6      6        106
     7      7        107
     8      8        108


Sample weight table

POINTGRID_WT item definitions

COLUMN  ITEM NAME   WIDTH  OUTPUT  TYPE N.DEC
    1   CODE         5      5     I      -
    6   WEIGHT       5      5     I      -

POINTGRID_WT listing of records

Record   CODE WEIGHT
     1    102     1
     2    103     3
     3    104     5
     4    105     9
     5    106     7


Point Distance

Computes the point-to-point distance between each point in a coverage to all points in the same or another coverage, within a specified Search radius.

The results are recorded in an Output table containing items for the internal numbers and DISTANCE. The precision for DISTANCE is the higher of the two input coverages, that is, either

COLUMN    ITEM NAME            WIDTH  OUTPUT  TYPE  N.DEC
     1    <From coverage>#         4       6     B      -
     5    <To coverage>#           4       6     B      -
     9    DISTANCE                 4      12     F      3
                                     (single precision)
Or
     9    DISTANCE                 8      18     F      5
                                     (double precision)

Notes

DISTANCE is set to 0 when no match is found within the Search radius for a particular point. If no matching points are found, the tool stops and gives a warning.

Point Distance will not work if either coverage contains more than 130,000 points.

The Output table can become huge when both coverages contain many points. Use a smaller Search radius to limit the number of combinations.

Calculating distances between all points in the same coverage

Related Topics


Calculating distances between all points in the same coverage

When calculating distances between all points in the same coverage, the two sets of points are distinguished by appending an 'A' and 'B' to the internal number item names, for example:

$Record      WELLS#A    WELLS#B     DISTANCE
      1         1          1           0.000
      2         1          7       6,638.164
      3         2          2           0.000
      4         2          3       8,876.223
      5         2          6      11,968.240
      6         3          2       8,876.223
      7         3          3           0.000
      8         3          4      10,435.500
      9         3          6      10,260.050
     10         3          8      11,763.860

Note that the DISTANCE between a point and itself is 0.


The coverage with points from which you want to measure the distance.


The coverage with points to which you want to measure the distance. This can be the same as the From coverage when measuring distances between points within the same coverage.


Search radius is the maximum distance surrounding a point to search for other points. The default is the diagonal width of the From coverage BND.

Use a smaller distance to limit the number of combinations.


The table you will create to store the distance calculation results.


Point Node

Transfers attributes from a point feature class to a node feature class. Each point in the Point coverage is matched against the nodes in the Node coverage. If any point is within the Search radius of a node, the attributes of that point are copied.

If more than one point matches to a node, then the nearest point is selected. If two or more points are the same distance from the node, then one is selected randomly. The Node coverage can be the same as the Point coverage, in which case the attributes of the point attribute table (PAT) are transferred to the node attribute table (NAT) within the Point coverage.

Notes

The <cover>-ID number for each matching point is stored as the node-ID number in the NAT. If there are no matches to a node, then the node-ID is equal to the internal node number.

If the Node coverage does not have an NAT, then the NAT is first built with Build using the NODE option.

Additional items from the PAT file are added to the NAT file. If an existing NAT file has additional attributes, items from the PAT will be appended after them. Item values with no matching points will be blank for character items and zero for numeric. Existing items and item values in the NAT file will be maintained.

If an item in the PAT exists in the NAT, the item values in the NAT are updated with values from the PAT.

ArcCatalog can be used to delete the points in a coverage containing lines and points after the point attributes have been transferred to the NAT.

Related Topics


Search radius is the maximum distance, in coverage units, which points and nodes can be apart for the attributes of the points to be copied. The default is the width or height of the Node coverage BND divided by 100, whichever is larger.


The point coverage whose attributes you want to transfer to a node feature class.


The maximum distance a point can be from a node to have its attributes copied. The default value is the width or height of the Node coverage BND divided by 100, whichever is larger.


The coverage whose node attributes you want to update or create.


Polygon Coverage to Grid

Converts data associated with polygon features to grid cell format. Imagine a grid drawn on a map of coverage features:  each cell in the grid is assigned a code according to the polygon(s) it overlays. The codes assigned to the cells are determined by the Value item and Lookup table. If a cell has more than one possible code (i.e., it contains two or more polygons), the code of the polygon with the greatest area in the cell is used.

It may not be desirable to always assign the code with the largest area to a cell. Small but important features could be lost from the grid if cell codes are assigned solely on the basis of area. In this case, a Weight table is used to associate an importance (weight) to a code. Codes with larger weights then take precedence over codes with lower weights. When weights are identical, the code with the largest area in the cell is used. If a code does not have an entry in the weight table, it is assigned a weight of 0.

Notes

The cell resolution should be chosen carefully and with consideration of these factors:

A cell size finer than the input resolution will not produce data at a finer resolution than the input data.

The Output grid cell resolution should be the same as or coarser than the input data.

Disk capacity and desired response time when determining the cell resolution that is best suited for your particular application.

Grid cell values must be in the range of 32-bit integers or floating-point numbers.

The Weight table is not used as a lookup table. It is used to assign weights to grid cell codes. These weights are used to resolve cases when a single cell can have several possible codes. The code with the highest weight will be assigned to the cell.

An Output grid value attribute table (VAT) table is created for resultant integer grids. The VAT will have items VALUE and COUNT. VALUE contains the number assigned to the cells in the Output grid, and COUNT is the number of cells in the Output grid that were assigned that cell value.

The projection file (PRJ) of the Input coverage is copied to the Output grid.

Sample lookup table

Sample weight table

Related Topics


The polygon coverage you want to convert to a grid.


Choose the polygon attribute whose values you want to assign to the grid’s VALUE item. The list shows only numeric items. The tool uses the internal polygon number by default.


Sample lookup table

POLYGRID.LUT item definitions

COLUMN  ITEM NAME   WIDTH  OUTPUT  TYPE N.DEC
    1   ATTRIBUTE2      4      5     I     -
    5   CODE            5      5     I     -

POLYGRID.LUT listing of records

Record  ATTRIBUTE2  CODE
     1      1        101
     2      2        102
     3      3        103
     4      4        104
     5      5        105
     6      6        106
     7      7        107
     8      8        108


Sample weight table

POLYGRID_WT item definitions

COLUMN  ITEM NAME   WIDTH  OUTPUT  TYPE N.DEC
    1   CODE            5      5     I     -
    6   WEIGHT          5      5     I     -

POLYGRID_WT listing of records

Record   CODE  WEIGHT
     1    102      1
     2    103      3
     3    104      5
     4    105      9
     5    106      7


Polygon Coverage to Region

Converts polygons to regions in a one-to-one mapping in a region subclass. Each polygon in the Input coverage becomes a region in the Output subclass. Attributes in the polygon attribute table (PAT) are copied to the corresponding region subclass PAT. The Output coverage can be the same as the Input coverage; if so, the Output subclass is then created in the Input coverage.

Notes

The Input coverage must have polygon topology.

The tool can be used with an Input coverage that does not have arc topology.

The tool builds region topology for the Output subclass. Topology in the Input coverage is maintained in the Output coverage.

Related Topics


The coverage with polygons you want to convert to a region subclass. It must have polygon topology.


The coverage you will create. It can be the same as the Input coverage; the Output subclass is then created in the Input coverage.


The region subclass you will create. The name can be up to 13 characters, and must not start with a numeric character.


A list of available data set prefixes found in the current directory.


A list of available directories.


Press OK when the desired  prefix is selected.


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Project Wizard

Changes the coordinate system of your dataset (coverage or grid), including its datum or spheroid. The wizard supports coordinate transformations between any two of the projections listed on the projections panel. It can be used to:

convert a dataset between a spherical coordinate system with angular units (such as Geographic) and a planar coordinate system with linear units. Most ArcToolbox tools, among them Build and Clean, assume you have a planar, 2D dataset. So if your dataset is in a geographic coordinate system in Decimal Degrees (DD, angular units), the Project Wizard projects your dataset to any suitable projected coordinate system in linear units (meters or feet).

change a dataset’s projection. Some ArcToolbox tools that work with multiple datasets require that the input datasets have the same projection and datum. To see an example, click [image].

Map projections

Notes

Before using the Project Wizard, your dataset must have a projection file (PRJ) that records its projection, projection parameters, and datum and spheroid. Use the Define Projection Wizard to create a projection file if your dataset does not have one.

Recommended post-processing

The Project Wizard copies feature attribute tables from the input coverage to the output coverage. Because clipping is possible, Project may not maintain feature topology. For example, polygons located along an edge may no longer close if part of the feature has been clipped. After Project has finished processing, you may need to relink attributes, and use other tools to rebuild topology and close boundary polygons. A feature might be deleted from a coverage but its attributes will remain in the polygon attribute table (PAT) until you Build or Clean. The Project Wizard does not rebuild topology.

If regions exist in the input coverage, regions in the output coverage will be preliminary regions. When the Build tool is used to recreate the polygon topology, region topology will also be recreated.

Related Topics


Selecting a projection

Transforming a curved surface represented by angular units (Degrees/Radians) in a spherical coordinate system into a planar surface represented by linear units (feet/meters) in a Cartesian coordinate system involves distortions in area, shape, distance and direction. Fixing one involves compromising the other three. For example, the Albers Equal Area projection offers true area at the cost of the other three properties. It is useful for thematic maps. On the other hand, the Azimuthal projection gives true direction and is useful for navigation maps.

On the wizard, the description displayed to the right of the projecton list provides information to assist you in selecting the most suitable projection for your data.

Check the Suggest a projection based on these characteristics of your data: box to get a short list of suitable projections, based on the Extent, Orientation and Latitude of your dataset.

Following are short descriptions of the supported projections, highlighting their property, type, extent, orientation, latitude, general use and suitability to various tasks.

  Alaska_E

  Alaska Grid

  Albers Equal-Area

  Azimuthal Equidistant

  Bipolar Oblique

  Bonne

  Cassini

  Chamberlin Trimetric

  Craster Parabolic

  Cylindrical Equal-Area

  Cylindrical (Oblique-Two Points)

  Cylindrical (Oblique-Azimuth)

  Eckert IV

  Eckert VI

  Equidistant (1 std parallel)

  Equidistant (2 std parallels)

  Equirectangular

  Flat Polar Quartic

  Gall Stereographic

  Geocentric

  Geographic

  Gnomonic

  Great Britain Grid

  Grinten

  Hammer-Aitoff

  Lambert Conformal

  Lambert Azimuthal

  Local

  Mercator

  Miller

  Mollweide

  New Zealand Grid

  Oblique Mercator (2 points)

  Oblique Mercator (Azimuth)

  Orthographic

  Perspective

  Polar

  Polyconic

  Robinson

  RSO

  Simple Conic (1 std parallel)

  Simple Conic (2 std parallels)

  Sinusoidal

  Space Oblique Mercator

  State Plane Coordinate System

  Stereographic (Oblique view)

  Stereographic (Equatorial view)

  Stereographic (Polar view)

  Times

  Transverse Mercator

  Two Point Equidistant

  UPS

  Universal Transverse Mercator (UTM)


Alaska_E

Property: Conformal (preserves local shape).
Type: Planar (Modified Stereographic).
Extent: Regions.
Orientation: No predominant orientation.
Latitude: High-Latitude.
General use: USGS maps.

Suitable for mapping the state of Alaska.


Alaska Grid

Property: Conformal (preserves local shape).
Type: Planar (Modified Stereographic).
Extent: Regions.
Orientation: No predominant orientation.
Latitude: High-Latitude.
General use: USGS maps.

Suitable for mapping the state of Alaska. Gives the lowest distortion in scale, the scale factor ranging from 0.997 to 1.003 for the entire state of Alaska. Distortion increases rapidly outside Alaska.


Albers Equal-Area

Property: Equal Area (preserves proportional areas).
Type: Conic.
Extent: Continents.
Orientation: East-West
Latitude: Mid-Latitude.
General use: Thematic, presentation and USGS maps.

Suitable for medium scale thematic mapping of continents and regions spanning in the East-West direction. Gives true scale along the two standard parallels. Scale distortion rapidly increases away from the parallels. It is best to confine the latitude range of the study area to 35°.


Azimuthal Equidistant

Property: Equidistant and Azimuthal (both distance and direction are accurate from the center point outwards).
Type: Planar.
Extent: Hemispheres and continents.
Orientation: No predominant orientation.
Latitude: Polar, Mid-Latitude, Equatorial.
General use: Topographic, navigation and USGS maps.

Suitable for large scale navigation and topographic maps covering the polar regions using the polar aspect. It is best to limit the polar area within a 30° radius. This projection can also handle equatorial and oblique aspects for mapping locations on or near the equator and mid-latitude locations between the poles and the equator.


Bipolar Oblique

Property: Conformal (preserves local shape).
Type: Conic.
Extent: Continents.
Orientation: North-South/Oblique
Latitude: Mid-Latitude, Equatorial.
General use: Geologic, presentation and USGS maps.

Custom designed projection for mapping North and South America together.


Bonne

Property: Equal Area (preserves proportional areas).
Type: Pseudoconic.
Extent: Continents.
Orientation: East-West.
Latitude: Mid-Latitude.

Suitable for mapping France and Ireland, along with Morocco and some other Mediterranean countries. Gives true scale along the Central Meridian and all parallels.


Cassini

Property: True scale along Central Meridian, and along lines perpendicular to the Central Meridian.
Type: Cylindrical.
Extent: Continents.
Orientation: North-South.
Latitude: Pole to Pole.
General use: Topographic maps.

Suitable for topographic mapping of areas predominantly North-South in extent. This transverse cylindrical projection is neither equal-area nor conformal.


Chamberlin Trimetric

Property: Nearly true distance from any 3 widely spaced points to any other point.
Type: Modified Planar.
Extent: Continents.
Orientation: No predominant orientation.
Latitude: Pole to Pole.

Suitable for mapping continents. For best results, the 3 selected input points should be widely spaced near the edge of the study area.


Craster Parabolic

Property: Equal Area (preserves proportional areas).
Type: Pseudocylindrical.
Extent: World.
Orientation: No predominant orientation.
Latitude: Equatorial.

Suitable for making thematic maps of the world.


Cylindrical Equal-Area

Property: Equal Area (preserves proportional areas).
Type: Cylindrical.
Extent: Regions and continents.
Orientation: East-West:
Latitude: Equatorial.
General use: Presentation maps.

Suitable for making presentation maps of countries and continents along the equator.


Cylindrical (Oblique-Two Points)

Property: Equal Area (preserves proportional areas).
Type: Cylindrical.
Extent: Regions and continents.
Orientation: Oblique.
Latitude: A narrow band surrounding the straight line joining the 2 input points.
General use: Presentation maps.

Suitable for making presentation maps of countries and continents spanning the line defined by the 2 points.


Cylindrical (Oblique-Azimuth)

Property: Equal Area (preserves proportional areas).
Type: Cylindrical.
Extent: Regions and continents.
Orientation: North-South.
Latitude: Mid-Latitude.
General use: Presentation maps.

Suitable for making presentation maps of areas spanning in the North-South direction.


Eckert IV

Property: Equal Area (preserves proportional areas).
Type: Pseudocylindrical.
Extent: World.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Thematic maps.

Suitable for thematic maps of the world. Shapes are stretched North-South 40% along the equator relative to the East-West dimension. Scale is true along parallels 40° 30' North and South.


Eckert VI

Property: Equal Area (preserves proportional areas).
Type: Pseudocylindrical.
Extent: World.
Orientation: East-West.
Latitude: High-Latitude.
General use: Thematic maps.

Suitable for thematic maps of the world. Shapes are stretched North-South 29% along the equator relative to the East-West dimension. Scale is true along parallels 49° 16' North and South.


Equidistant (1 std parallel)

Property: Equidistant (true distance along the Central Meridian and standard parallel).
Type: Conic.
Extent: Regions.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Presentation maps

Suitable for presentation maps of small countries and regions stretching in the East-West direction. It is best to limit the range of latitude to 30°. Distortion in shape and area increases with distance from the standard parallel.


Equidistant (2 std parallels)

Property: Equidistant (true distance along the Central Meridian and  the two standard parallels).
Type: Conic.
Extent: Regions.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Presentation maps

Suitable for presentation maps of small countries and regions stretching in the East-West direction. It is best to limit the range of latitude to 30°. Distortion in shape and area increases with distance from the 2 standard parallels.


Equirectangular

Property: Equidistant (true distance along all Meridians and   standard parallels).
Type: Cylindrical.
Extent: Regions.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: USGS maps.

Suitable for simple portrayals of regions or the world with minimum geographic data, such as index maps. A simple projection based on a grid of equal rectangles.


Flat Polar Quartic

Property: Equal Area (preserves proportional areas).
Type: Pseudocylindrical.
Extent: World.
Orientation: East-West.
Latitude: Equatorial.
General use: Thematic maps.

Suitable for thematic maps of the world. Shapes are stretched North-South along the equator relative to the East-West dimension. Scale is distorted everywhere except along Latitudes 33°45' North and South.


Gall Stereographic

Property: Conformal (true shape and area along Latitudes 45° North and South).
Type: Cylindrical (Stereographic).
Extent: World.
Orientation: No predominant orientation.
Latitude: Mid-Latitude.
General use: Presentation maps.

Suitable for simple world maps. Gives a stereographic view of the world based on 2 standard parallels at 45° North and South.


Geocentric

Not truly a map projection, because it works in a three-dimensional coordinate system. GEOCENTRIC converts longitude-latitude coordinate pairs into x-, y-, z-values based on an ellipsoidal earth. These values are in a rectangular coordinate system with linear units.


Geographic

Not a map projection. The Geographic Reference System maps locations on a globe using latitude and longitude. This system treats the globe as if it were a sphere or spheroid. Uses angular units DD, DM, DS or Radians.


Gnomonic

Property: Azimuthal (true direction from center).
Type: Planar(Perspective).
Extent: Regions.
Orientation: No predominant orientation.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Navigation and presenatation maps.

Suitable for navigation maps. This azimuthal projection uses the center of the Earth as its perspective point. All meridians and the equator are straight lines. Best to limit study area within 60° from the center.


Great Britain Grid

Property: Conformal (preserves local shape).
Type: Cylindrical.
Extent: Regions
Orientation: North-South.
Latitude: High-Latitude.
General use: Topographic and geologic maps.

Suitable for large and medium scale topographic maps of Great Britain. The Great Britain National Grid is based on a Transverse Mercator projection using the Airy spheroid. The scale factor along the Central Meridian is 0.9996. The origin is 49° North and 2° West.


Grinten

Property: Compromise (neither true area/shape nor distance/direction).
Type: Circular.
Extent: World.
Orientation: No predominant orientation.
Latitude: Mid-Latitude/Equatorial.
General use: Presentation and USGS maps.

Suitable for presentation maps of the world. Similar to Mercator but portrays the world as a circle, with a curved graticule. Best to limit the study area within parallels 75° North and South. Area is distorted less than with Mercator projection, and shapes are distorted less than on equal-area projections. Gives true scale along the Equator.


Hammer-Aitoff

Property: Equal Area (preserves proportional areas).
Type: Modified Planar.
Extent: World.
Orientation: No predominant orientation.
Latitude: Equatorial.
General use: Thematic and presentation maps.

Suitable for thematic and presentation maps of the whole world. The Hammer-Aitoff projection is a modification of the Lambert Azimuthal Equal-Area projection. It uses the intersection point of the Equator and the Central Meridian as the point of tangency.


Lambert Conformal

Property: Conformal (preserves local shapes).
Type: Conic.
Extent: Continents.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Topographic, geologic, presentation, navigation and USGS maps.

Suitable for large scale and medium scale topographic, geologic, and navigation maps of continents and countries spanning in the East-West direction along Mid-Latitude. It is best to limit the Latitude range to within 35°. It is similar to the Albers Conic Equal-Area projection, except that it portrays shape more accurately than area. The State Plane Coordinate System of USA applies this projection for all state plane zones that spread East to West.


Lambert Azimuthal

Property: Equal Area (preserves proportional areas) and Azimuthal (true direction from central point).
Type: Planar.
Extent: Hemispheres and Continents.
Orientation: No predominant orientation.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Geologic, thematic, presentation, navigation and USGS maps.

Suitable for thematic, presentation and navigation maps of continents and hemispheres. Preserves the area of individual polygons while simultaneously maintaining true direction from the central point. Software cannot process any area extending beyond 90° from the central point. Study area must lie within a hemisphere. Best suited for individual land masses that are symmetrically proportioned, either round or square.


Local

A specialized map projection that does not take into account the curvature of the Earth. Designed for very large-scale mapping applications.


Mercator

Property: Conformal (preserves local shapes).
Type: Cylindrical.
Extent: Regions.
Orientation: East-West.
Latitude: Equatorial.
General use: Topographic, geologic, presentation, navigation and USGS maps.

Suitable for large scale topographic, presentation, and navigation maps of regions and countries spanning in the East-West direction along the Equator. It is best to limit the study area between parallels 70° North and South. The poles cannot be shown. Originally created to display accurate compass bearings for sea travel. Any straight line drawn on a Mercator map will show the actual compass bearing.


Miller

Property: Compromise (distorts area, shape, distance, and direction).
Type: Cylindrical.
Extent: World.
Orientation: East-West.
Latitude: Equatorial.
General use: Thematic and USGS maps.

Suitable for making thematic maps of the world. Similar to the Mercator projection, except that the polar regions are not as distorted. The lower distortion in area comes at the cost of higher distortion in shape and direction. Gives true distances along the Equator.


Mollweide

Property: Equal Area (preserves proportional areas).
Type: Pseudocylindrical.
Extent: World.
Orientation: No predominant orientation.
Latitude: Equatorial.
General use: Thematic maps.

Suitable for small scale thematic maps of the world. Gives true scale along parallels 40° 44' North and South.


New Zealand Grid

Property: Conformal (preserves local shapes).
Type: Modified Cylindrical.
Extent: Regions.
Orientation: Oblique.
Latitude: High-Latitude.
General use: Mapping of New Zealand.

Suitable for mapping the country of New Zealand. The standard projection for large-scale maps of New Zealand. The point of tangency is 41° South, 173° West. Uses the International spheroid. Area and scale distortions are less than 0.04% and 0.02% respectively for New Zealand.


Oblique Mercator (2 points)

Property: Conformal (preserves local shapes).
Type: Cylindrical.
Extent: Continents.
Orientation: Oblique.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Topographic and USGS maps.

Suitable for large scale and medium scale topographic mapping of regions having an oblique orientation. Used in the tilted Alaskan panhandle and for mapping in Switzerland, Madagascar and Borneo. Uses the Mercator projection rotated at an oblique angle, the central line being defined by 2 points. Gives true scale along the central line. Developed for large scale conformal mapping of areas that do not follow a North-South or East-West trend, but rather an oblique orientation.


Oblique Mercator (Azimuth)

Property: Conformal (preserves local shapes).
Type: Cylindrical.
Extent: Continents.
Orientation: Oblique.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Topographic and USGS maps.

Suitable for large scale and medium scale topographic mapping of regions having an oblique orientation. Used in State Plane Grids for the tilted pan handle of Alaska and for mapping in Switzerland, Madagascar and Borneo. Uses the Mercator projection rotated at an oblique angle, the central line being defined by a single point and direction (Azimuth angle) specified in DMS. Gives true scale along the central line. Developed for large scale conformal mapping of areas that do not follow a North-South or East-West trend, but rather are obliquely oriented.


Orthographic

Property: Azimuthal (true direction from central point).
Type: Planar (perspective).
Extent: Hemisphere.
Orientation: No predominant orientation.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Presentation and USGS maps.

Suitable for small scale presentation maps of the hemisphere. Limited to a view 90° from the central point. Only one hemisphere can be shown at a time. Gives the illusion of a 3-D globe by viewing the globe from an infinite distance.


Perspective

Property: Azimuthal (true direction from point of tangency).
Type: Planar (perspective).
Extent: Continents.
Orientation: No predominant orientation.
Latitude: Polar/Mid-Latitude/Equatorial.
General use: Presentation maps.

Suitable for small scale presentation maps of the hemisphere. Limited to a view 90° from the central point. Only one hemisphere can be shown at a time. Like the Orthographic projection, its perspective is from space. However, the perspective point is not at infinity but rather the height of the perspective point above the sphere can be specified by the user. This projection looks like a photograph taken vertically from a satellite or space vehicle.


Polar

Property: Conformal (preserves local shapes) and Azimuthal (true direction from the poles).
Type: Planar (perspective).
Extent: Hemisphere.
Orientation: No predominant orientation.
Latitude: Polar.
General use: Topographic, presentation and USGS maps.

Suitable for medium scale topographic and presentation maps of the polar regions. The Polar Stereographic projection can show all regions not included in the UTM Coordinate System, regions North of Latitude 84° N and South of Latitude 80° S. The central point is either the North Pole or the South Pole. One pole is viewed from another. Of all polar aspect planar projections, this one is conformal.


Polyconic

Property: Compromise (neither true area/shape nor distance/direction).
Type: Conic.
Extent: Continents
Orientation: North-South.
Latitude: Mid-Latitude.
General use: Topographic and USGS maps.

Suitable for large scale topographic maps of areas oriented North-South. This projection was used on USGS 7.5 and 15 minute topographic quad sheets from 1886 to around 1957. Polyconic uses 'many cones' for its methodology. Unlike other conic projections, the meridians are curved, rather than straight. Gives true scale along each parallel and the Central Meridian.


Robinson

Property: Compromise (neither true area/shape nor distance/direction).
Type: Pseudocylindrical.
Extent: World.
Orientation: No predominant orientation.
Latitude: Mid-Latitude/Equatorial.
General use: Thematic and presentation maps.

Suitable for small scale thematic and presentation maps of the world. Gives true scale along parallels 38° North and South.


RSO

Property: Conformal (preserves local shapes).
Type: Cylindrical.
Extent: Regions.
Orientation: Oblique.
Latitude: Mid-Latitude/Equatorial.
General use: Mapping Malaysia and Brunei.

Suitable for large scale topographic mapping of regions having an oblique orientation. Similar to the Oblique Mercator projection. Has two options for the national coordinate systems of Malaysia and Brunei.


Simple Conic (1 std parallel)

Property: Equidistant (preserves distance between 2 points).
Type: Conic.
Extent: Regions.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Presentation maps.

Suitable for small scale presentation maps of regions spanning in the East-West direction along Mid-Latitude. Based on one standard parallel. Parallels and Meridians are evenly spaced. Best to limit the range in Latitude to 30°.


Simple Conic (2 std parallels)

Property: Equidistant (preserves distance between 2 points).
Type: Conic.
Extent: Regions.
Orientation: East-West.
Latitude: Mid-Latitude.
General use: Presentation maps.

Suitable for small scale presentation maps of regions spanning in the East-West direction along Mid-Latitude. Based on two standard parallels. Parallels and Meridians are evenly spaced. Best to limit the range in Latitude to 30°.


Sinusoidal

Property: Equal Area (preserves proportional areas) and Equidistant (true scale along all parallels and the Central Meridian).
Type: Pseudocylindrical.
Extent: World
Orientation: North-South.
Latitude: Equatorial.
General use: Thematic and USGS maps.

Suitable for small scale thematic maps of the world. Gives lower distortion when study area is limited to a single land mass spanning vertically.


Space Oblique Mercator

Property: Nearly conformal (preserves local shape within the narrow band of Satellite scanning).
Type: Modified cylindrical.
Extent: Path of satellite.
Orientation: North-South.
Latitude: Pole to pole.
General use: Mapping satellite data.

Specifically designed for continuous mapping from satellite imagery. Best to limit study area within the narrow tracking range of the satellite.


State Plane Coordinate System

Property: Conformal (preserves local shape).
Type: Conic/Cylindrical.
Extent: Continents.
Orientation: North-South/East-West/Oblique.
Latitude: Mid-Latitude.
General Use: Topographic, geologic, presentation and USGS maps.

Suitable for large scale topographic maps of the United States. The State Plane Coordinate System is not a projection but a coordinate system that divides the United States into over 120 numbered sections or zones. Each zone has an assigned code number that defines the projection parameters for the region. Zones spanning North-South use Transverse Mercator. Zones spanning East-West use Lambert Conformal Conic. The tilted Alaskan pan handle uses Oblique Mercator. The NAD27 datum uses the Clarke 1866 spheroid. The NAD83 datum uses the GRS80 spheroid.


Stereographic (Oblique view)

Property: Conformal (preserves local shape) and Azimuthal (true direction from center point).
Type: Planar (stereographic).
Extent: Hemisphere.
Orientation: No predominant orientation.
Latitude: Mid-Latitude.
General use: Geologic, navigation and USGS maps.

Suitable for small scale navigation maps of the hemisphere. The center point for the oblique view could be anywhere on the surface of the earth. Best to limit study area within a radius of 90° from the center point.


Stereographic (Equatorial view)

Property: Conformal (preserves local shape) and Azimuthal (true direction from the center point).
Type: Planar (stereographic).
Extent: Hemisphere.
Orientation: No predominant orientation.
Latitude: Equatorial.
General use: Geologic, navigation and USGS maps.

Suitable for small scale navigation maps of the hemisphere. The center point for the Equatorial view is the equator. Best to limit study area within a radius of 90° from the center point.


Stereographic (Polar view)

Property: Conformal (preserves local shape) and Azimuthal (true direction from the poles).
Type: Planar (stereographic).
Extent: Hemisphere.
Orientation: No predominant orientation.
Latitude: Polar.
General use: Geologic, navigation and USGS maps.

Suitable for small scale navigation maps of the hemisphere. The center point for the Polar view is either the North Pole or the South Pole. Best to limit study area within a radius of 90° from the center point.


Times

Property: Compromise (neither true area/shape nor distance/direction).
Type: Pseudocylindrical.
Extent: World.
Orientation: No predominant orientation.
Latitude: Equatorial.
General use: Thematic and presentation maps.

Suitable for small scale thematic maps of the world. Gives true scale along the parallels 45° North and South.


Transverse Mercator

Property: Conformal (preserves local shape).
Type: Cylindrical.
Extent: Continents.
Orientation: North-South.
Latitude: Equatorial/Mid-Latitude.
General use: Topographic, geologic and USGS maps.

Suitable for large to medium scale topographic mapping of regions and continents spanning in the North-South direction. Similar to the Mercator projection, except that the axis of the cylinder is aligned along a meridian instead of the Equator. Used for UTM and State Plane zones spanning North-South. Best to limit study area to 15° on both sides of the Central Meridian.


Two Point Equidistant

Property: Equidistant (preserves distance between two points).
Type: Modified Planar.
Extent: Continents.
Orientation: No predominant orientation.
Latitude: Oblique.
General use: Thematic maps.

Suitable for small scale thematic maps of regions and continents. Shows true distance from either of two chosen points A and B to any other point on a map. Point A must be to the West of point B.


UPS

Property: Conformal (preserves local shapes) and Azimuthal (true direction from the poles).
Type: Planar (perspective).
Extent: Continents.
Orientation: No predominant orientation.
Latitude: Polar.
General use: Topographic, geologic, presentation and USGS maps.

Suitable for medium scale topographic and navigation maps of the polar regions. The Universal Polar Stereographic projection can show all regions not included in the UTM Coordinate System, regions North of Latitude 84° N and South of Latitude 80° S. The central point is either the North Pole or the South Pole. One pole is viewed from another. Of all polar aspect planar projections, this one is conformal. Derived from the Polar Stereographic projection with some standard parameters.


Universal Transverse Mercator (UTM)

Property: Conformal (preserves local shape).
Type: Cylindrical.
Extent: Regions.
Orientation: North-South.
Latitude: Equatorial/Mid-Latitude.
General use: Topographic and USGS maps.

Suitable for large to medium scale topographic mapping of regions and continents spanning in the North-South direction. Derived from the Transverse Mercator Projection, the UTM system divides the globe into sixty zones, each spanning six degrees of longitude. The limits of each zone are 84° North, 80° South. Regions beyond these limits use the Universal Polar Stereographic projection.


Setting projection parameters

Parameters vary by projection. View details on the parameter specific to your chosen projection to determine the appropriate input.

  Units

  1st and 2nd standard parallels

  Radius of the sphere of reference

  Scale factor

  Scale factor at center of projection

  Longitude of center of projection

  Projection origin

  Latitude of center of projection

  Latitude of origin of projection

  Latitude of standard parallel

  Latitude of true scale

  False easting, False northing

  X and Y Shift

  Azimuth

Examples of parameters for some common projections.

  Universal Transverse Mercator (UTM) coordinate system

  State Plane Coordinate System

  Lambert Conformal projection

  Transverse Mercator projection

  Geographic coordinate system


Selecting a datum

A Datum is a system of measurement that includes an initial starting point and a specific spheroid. Accepting the default will not change the datum.

Your dataset must have a datum defined if you want do a datum transformation such as from NAD 1927 (US-NADCON) to NAD 1983 (US-NADCON).

To define a datum for your dataset, use the Define Projection Wizard.


US-NADCON is a datum transformation method that uses a grid to calculate the coordinate differences between datums. The method has an approximate accuracy of 0.15 to 0.5 meters. It is best suited for mapping at scales of 1:200 and smaller (e.g. block, parcel and building level) for the United States, Puerto Rico, and the Virgin Islands, but only for conversion between the NAD27, the NAD83, the High Precision GPS Network (HPGN) readjustment of NAD83 and selected local island datums.


State Plane Coordinate System (SPCS) is a coordinate system that divides all fifty states of the United States, Puerto Rico, the U.S. Virgin Islands, Guam and Samoa into over 120 zones. Each zone has an assigned code number that defines the projection parameters for the region. The Project Wizard supports two sets of zone codes. The FIPS zone is the more up-to-date and standard set. The ‘zone’ codes are an older and outdated BLM system. SPCS requires using either NAD27, NAD83 or HPGN for the datum. Some FIPS zones are only supported for either NAD27 or NAD83 but most can be used for either datum.

SPCS Zone Names, FIPSZONE,
and ZONE numbers.

State & Zone Name	Datum	FIPSZONE	ZONE
Alabama, East		101	3101
Alabama, West		102	3126
Alaska, Zone 1		5001	6101
Alaska, Zone 2		5002	6126
Alaska, Zone 3		5003	6151
Alaska, Zone 4		5004	6176
Alaska, Zone 5		5005	6201
Alaska, Zone 6		5006	6226
Alaska, Zone 7		5007	6251
Alaska, Zone 8		5008	6276
Alaska, Zone 9		5009	6301
Alaska, Zone 10		5010	6326
Arizona, East		201	3151
Arizona, Central		202	3176
Arizona, West		203	3201
Arkansas, North		301	3226
Arkansas, South		302	3251
California, Zone I		401	3276
California, Zone II		402	3301
California, Zone III		403	3326
California, Zone IV		404	3351
California, Zone V		405	3376
California, Zone VI		406	3401
California, Zone VII	NAD27	407	3426
Colorado, North		501	3451
Colorado, Central		502	3476
Colorado, South		503	3501
Connecticut		600	3526
Delaware		700	3551
Florida, North		903	3576
Florida, East		901	3601
Florida, West		902	3626
Georgia, East		1001	3651
Georgia, West		1002	3676
Hawaiian Islands, Zone 1		5101	5876
Hawaiian Islands, Zone 2		5102	5901
Hawaiian Islands, Zone 3		5103	5926
Hawaiian Islands, Zone 4		5104	5951
Hawaiian Islands, Zone 5		5105	5976
Idaho, East		1101	3701
Idaho, Central		1102	3726
Idaho, West		1103	3751
Illinois, East		1201	3776
Illinois, West		1202	3801
Indiana, East		1301	3826
Indiana, West		1302	3851
Iowa, North		1401	3876
Iowa, South		1402	3901
Kansas, North		1501	3926
Kansas, South		1502	3951
Kentucky, North		1601	3976
Kentucky, South		1602	4001
Louisiana, North		1701	4026
Louisiana, South		1702	4051
Louisiana, Off Shore		1703	6426
Maine, East		1801	4076
Maine, West		1802	4101
Maryland		1900	4126
Massachusetts, Mainland		2001	4151
Massachusetts, Island		2002	4176
Michigan, East	Old	2101	4201
Michigan, Central	Old	2102	4226
Michigan, West	Old	2103	4251
Michigan, North	New	2111	6351
Michigan, Central	New	2112	6376
Michigan, South	New	2113	6401
Minnesota, North		2201	4276
Minnesota, Central		2202	4301
Minnesota, South		2203	4326
Mississippi, East		2301	4351
Mississippi, West		2302	4376
Missouri, East		2401	4401
Missouri, Central		2402	4426
Missouri, West		2403	4451
Montana, North	NAD27	2501	4476
Montana, Central	NAD27	2502	4501
Montana, South	NAD27	2503	4526
Montana	NAD83	2500
Nebraska, North	NAD27	2601	4551
Nebraska, South	NAD27	2602	4576
Nebraska	NAD83	2600
Nevada, East		2701	4601
Nevada, Central		2702	4626
Nevada, West		2703	4651
New Hampshire		2800	4676
New Jersey		2900	4701
New Mexico, East		3001	4726
New Mexico, Central		3002	4751
New Mexico, West		3003	4776
New York, East		3101	4801
New York, Central		3102	4826
New York, West		3103	4851
New York, Long Island		3104	4876
North Carolina		3200	4901
North Dakota, North		3301	4926
North Dakota, South		3302	4951
Ohio, North		3401	4976
Ohio, South		3402	5001
Oklahoma, North		3501	5026
Oklahoma, South		3502	5051
Oregon, North		3601	5076
Oregon, South		3602	5101
Pennsylvania, North		3701	5126
Pennsylvania, South		3702	5151
Rhode Island		3800	5176
South Carolina, North	NAD27	3901	5201
South Carolina, South	NAD27	3902	5226
South Carolina	NAD83	3900
South Dakota, North		4001	5251
South Dakota, South		4002	5276
Tennessee		4100	5301
Texas, North		4201	5326
Texas, North Central		4202	5351
Texas, Central		4203	5376
Texas, South Central		4204	5401
Texas, South		4205	5426
Utah, North		4301	5451
Utah, Central		4302	5476
Utah, South		4303	5501
Vermont		4400	5526
Virginia, North		4501	5551
Virginia, South		4502	5576
Washington, North		4601	5601
Washington, South		4602	5626
West Virginia, North		4701	5651
West Virginia, South		4702	5676
Wisconsin, North		4801	5701
Wisconsin, Central		4802	5726
Wisconsin, South		4803	5751
Wyoming, I, East		4901	5776
Wyoming, II, East Central		4902	5801
Wyoming, III, West Central		4903	5826
Wyoming, IV, West		4904	5851
Puerto Rico Zone	NAD27	5201	6001
St. Croix Zone	NAD27	5202	6051
Puerto Rico & St. Croix	NAD83	5200
American Samoa		5300
Guam Island		5400


Example

Suppose you want to use the Append Wizard to join a State Plane dataset with the following parameters:

Projection: State Plane
Units: feet
FIPS zone: 401
Datum: NAD 1927 (US-NADCON)

with an Albers Equal-Area dataset with these parameters:

Projection: Albers Equal-Area
Units: meters
Datum: NAD 1927 (US-NADCON)
1st Standard parallel: 29 30 00 DMS
2nd Standard parallel: 45 30 00 DMS
Longitude of center of projection: -95 00 00 DMS
Latitude of origin of projection: 23 00 00 DMS
False Easting: 5000000 meters
False Northing: 0 meters

Use the Project Wizard to change the State Plane dataset to Albers Equal-Area.


Map projections

A coverage or grid can maintain an explicit definition of the coordinate system in which it is stored. This can be created using the Define Projection Wizard. If not defined, the projection will be listed as Unknown. Projection information is stored in the dataset's PRJ file.

Map projections allow areas on the surface of the Earth (a spheroid) to be represented on a map (a flat surface). A projection more precisely equates locations on a map with their true locations on the Earth. However, expressing a three-dimensional surface in two dimensions involves distortion of some parameter, either shape, area, distance, or direction, and various projections cause different kinds of distortion. The individual characteristics of the projections make each useful for some applications and not useful for others.


Query Builder

Constructs a query, composed of one or more selection expressions, to operate on the selected feature class. All features in the input coverage are divided into two sets: a selected set and an unselected set. The selected set comprises the features to be merged, extracted or deleted. At the start of the tool, all features are selected. You must use a query to identify the features to be in the final selected set.

As you build each selection expression, it is placed into the Current expression textbox. Use the Down arrow to move it to the list below, and create more selection expressions as required. Expressions are processed in the order listed; you can move them up and down to get the proper order. You can save the query to disk to be used later in the same or another tool.

Click the View items… button to see the item definitions or values in your table (from the Values tab, click an item name to see its Values).

Uncheck Update values if you don't need to see the Values every time you click on a different Item. This can save considerable time if there are many values.

  Steps to build a query

  Steps to edit a query

Selection expressions

A query is composed of one or more selection expressions. A selection expression, or logical expression, is a combination of items, system items, system variables, literals and arithmetic logical operators from which a value of TRUE or FALSE is derived; for example, HRS-WRKD * HRLY-WAGE >= 600 AND MONTH = 5.

In ArcToolbox, selection expressions are made up of Selection methods, operands (such as Items and Values), Operators and Connectors.

Selection methods

Operands

Operators

Connectors

Notes

Indexed items can speed processing.

You can use up to ten selection expressions (maximum of 320 characters for each expression) to build a complex query.

Other controls on the Query Builder.

The Query Builder is used in the following tools:  Clean Regions, Eliminate, Query Regions, Select, Create Tin Wizard and Extract Wizard.

Related Topics


The Selection methods available to build a query:

Subset – creates a subset of the currently selected features for which the query is true.

Add – adds the features for which the query is true to the currently selected set.

Switch – replaces the selected set with the currently unselected set.


Subset – creates a subset of the currently selected features for which the query is true.


Add – adds the features for which the query is true to the currently selected set.


Switch – replaces the selected set with the currently unselected set.


Lists the Items from the Input feature class.


The Operators available to build a query.


<   less than: operand1 is less than operand2.


=   equal to: operand1 is equal to operand2.


>   greater than: operand1 is greater than operand2.


>=   greater than or equal to: operand1 is greater than or equal to operand2.


<>   not equal to: operand1 is not equal to operand2.


<=  less than or equal to: operand1 is less than or equal to operand2.


In   contained in: operand1 is contained in operand2.


(   opening round bracket used—with a space after it—to clarify relationships between the elements in a selection expression.


)   closing round bracket used—with a space before it—to clarify relationships between the elements in a selection expression.


like   operand1 is like operand2.


CN   contains: operand1 contains operand2.


NC   does not contain: operand1 i does not contain operand2.


and    selection expression1 and selection expression2 must be true.


not   only the left selection expression must be true.


or   at least one selection expression must be true; one or more can be true.


->  indicates a value range.


{   opening curly bracket used—with a space after it—with the In operator to clarify relationships between the elements in an In selection expression.


}   closing curly bracket used—with a space before it—with the In operator to clarify relationships between the elements in an In selection expression.


/   the arithmetic operator for division.


*   the arithmetic operator for multiplication.


+   the arithmetic operator for addition.


-   the arithmetic operator for subtraction.


*   used with like as wildcard for characters.


xor   only one of two selection expressions must be true; either one can be true.


The Connectors available to build a query.


Lists the Values for the selected Item.


The selection expression you are currently building.


The selection expressions you have built.


Saves the query you have built to a file.


Opens a browser to choose from queries you have previously built and saved.


Deletes the selected selection expression from the list.


Removes the last element you have added to the selection expression.


Clears the selected selection expression or Query.


Adds the selection expression you have built to the list below.


Up  moves the selection expression up on the list. Selection expressions are processed top down.


Down  moves the selection expression down on the list. Selection expressions are processed top down.


The Selection method for this expression.


Passes the query you have built to the tool and dismisses the Query Builder.


Cancels your query and closes the Query Builder.


Opens a Help window with an overview of how the Query Builder works.


Opens the Table Information form that shows the item values and definitions of the specified feature attribute table.


Choose whether to update the Values in the list.

Checked – updates values each time a new Item is selected. Populating the list can take time, depending on how many values there are.

Unchecked – does not update the values when a new Item is selected. If items have many values, this can save time.


Selection Methods

The Query Builder provides three selection methods.

Subset – reduces the selected set of records to those for which the selection expression is true. If no selection expression follows, the selected set will be empty. To see examples, click [image].

Add – adds the features for which the selection expression is true to the currently selected set. If no selection expression follows, the selected set will contain all features. To see examples, click [image].

Switch – reverses the current selection to the unselected set. It is not followed by a selection expression.


Operands

Operands include:

The name of an Item in a table (e.g., STREAMS-ID).

A constant numerical Value (e.g., 10).

A character string in single quotation marks (e.g., ‘HIGH’ or ‘H*’).

An internal variable (e.g., $RECNO).

A set of values (e.g., {1,2,6->14,20}).

The simplest selection expression uses two operands and one operator and looks like this:

<operand1> <operator> <operand2>.

For example:

Zip code = 92373


Operators

Operators are arithmetic or logical symbols that denote the operation to be performed.

Logical operators:

  less than – operand1 is less than operand2

  greater than – operand1 is greater than operand2

  equal to – operand1 is equal to operand2

  not equal to – operand1 is not equal to operand2

  less than or equal to – operand1 is less than or equal to operand2

  greater than or equal to – operand1 is greater than or equal to operand2

  contains – operand1 contains operand2

  does not contain – operand1 does not contain operand2

  contained in – operand1 is contained in operand2

  range – used within curly brackets of an In operand to separate the values forming the lower- and upper-inclusive limits of the range. A range defined between two character strings is based on the ASCII number sequence.

   opening and closing curly brackets are used with In—with a space after and before each bracket—to enclose the set of numeric or character string constants. Individual values withing the brackets must be separated by commas, unless a range is used.

   opening and closing parentheses are used to change the order of operations within a selection expression. All logical operators and connectors have equal precedence, and operations are performed in sequence from left to right. Parentheses are used to specify that logic within them is performed first. Operations inside the innermost set of parentheses have the highest precedence.

  like – operand1 is like the wildcard character specified in operand2. For example, like ‘M*’ will match ‘M’, ‘MAIN’, ‘M1’, ‘MAINE’, ‘M.1’, and any other character string beginning with the letter ‘M’.

  * – used with like as wildcard for characters.

Arithmetic operators:

  division

  multiplication

  addition

  subtraction


Connectors

Connectors, also known as logical connectors and as Boolean operators, are keywords that specify how to combine simple logical expressions into complex expressions. The available Connectors are:

and – both selection expressions must be true.

not – only the left and not the right selection expression must be true.

or – at least one selection expression must be true; one or more can be true.

xor – only one of the two selection expressions must be true; either one can be true.

A complex selection expression might look like this:

<operand1> <operator> <operand2> OR <operand1> <operator> <operand3>

For example:

Zipcode = 92373 OR  Zipcode = 92375


Indexed items can speed processing

Items are indexed to speed up query processing when selecting features. To benefit from indexed items, the following requirements must be met:

 Use indexed items only with these operators:

= (equal)

<> (not equal)

> (greater than),

>= (greater than or equal)

< (less than),

<= (less then or equal)

 Use indexed items only in simple queries such as

<operand1> <operator> <operand2>

Zip code	=	92373

  Steps to create an item index in ArcCatalog.


A selection expression, or logical expression, is a combination of items, system items, system variables, literals and arithmetic logical operators from which a value of TRUE or FALSE is derived; for example, HRS-WRKD * HRLY-WAGE >= 600 AND MONTH = 5.


Other controls on the Query Builder

  moves the selected expression up. The expressions are processed in the order they are listed.

  moves the selected expression down. The expressions are processed in the order they are listed.

  saves your query.

  opens a browser to retrieve a saved query.

  deletes the selected selection expression from the list.


Steps to build a query

1	Choose a Selection method, for example, Subset.

2	Choose an item from the Items list; for example, LENGTH. (Notice that the Values list on the right is populated.)

3	Choose an Operator from those available, for example, <.

4	Choose a value in the Values list, for example, 5000.

5	To extend or constrain your query, choose a Connector such as and and repeat steps 2 through 4, and possibly 5 as needed.

6	Click the Down arrow to add the Current expression to the list of expressions below.

7	Repeat Steps 2 through 6 to build additional expressions in your query.

8	When your query is complete, click OK to transfer the query to the tool or wizard and exit the Query Builder.


Steps to edit a query

To add a new selection expression:

1	Click on the next empty line in the expression list.

2	Choose the appropriate pieces from Selection method, Items, Operators, and Values lists .

3	Click  [image]  to add the expression to the list.

4	Use [image]  and  [image]  to change the order of the selection expressions, as required.

5	Repeat steps as needed.

6	Click OK to return the edited query to the tool or wizard.

To edit an existing selection expression:

1	Choose the expression you want to edit by clicking the selection expression in the list at the bottom. This expression is moved up into Current expression.

2	Use the cursor to clear all or part of the expression.

3	Choose the appropriate pieces from Selection method, Items, Operators, and Values.

4	Click  [image]  to replace the expression in the list.

5	Use [image]  and  [image]  to change the order of the selection expressions, as required.

6	Repeat steps as needed.

7	Click OK to return the edited query to the tool or wizard.


Query Regions

Creates new regions based on the attribute values of input region or polygon layers and aggregates regions according to specified attribute items.

Query Regions operates on polygons and multiple region subclasses in the same coverage. It can select regions and polygons with logical expressions, and at the same time dissolve selected features through a list of specified region items. It can produce contiguous or noncontiguous Output regions. It is therefore very versatile and has, among others, the following capabilities:

Mimics the traditional overlay commands, where the layers are region subclasses in an integrated coverage.

Produces results equal to those of the Polygon Coverage to Region tool and the Dissolve Regions tool, although not with the same efficiency.

Selects overlap conditions between overlapping regions.

Converts noncontiguous regions to contiguous regions and vice versa.

Reports on containment and partial containment.

  The integrated region coverage model

  Selection files

  How to build a query

  Noncontiguous and contiguous

  Notes for Region items

Notes

Output subclass is created in the Input coverage unless you specify a different Output coverage. If Output subclass is already present then new regions will be appended to it. If Output coverage is different from Input coverage, only those polygons required for the Output regions are transferred to the Output coverage. All features related to these polygons are also transferred to Output coverage. The AAT and NAT are maintained.

Any route-systems defined in the coverage will be maintained in the Output coverage by deleting any routes or sections that are not part of the Output coverage.

ADD and TRN files in the Input coverage will be copied to the Output coverage. The Output coverage copies of these files will contain all of the original records and will need to be rebuilt using the ArcInfo commands ADDRESSBUILD and TURNTABLE.

The projection file (PRJ) will be copied to the Output coverage.

Related Topics


The integrated region coverage model

Query Regions operates on the integrated region coverage model. In an integrated coverage, thematic data layers are stored as region subclasses. Each base polygon in the Input coverage is part of a number of regions for a given subclass. These are the regions ‘above’ the polygon. The polygon and the regions above it form a subclass ‘stack’.

If only a single subclass is involved in a query, the selection expressions are evaluated for each member of the stack, and if true, the member of the stack is selected as part of a candidate Output region.

If multiple subclasses are present, and a single polygon has multiple subclass stacks with more than one region, Query Regions will combine the stacks in the form of a Cartesian product, and evaluate the attributes according to the logical expressions for each member of the product.

Output items are assigned to each selected Cartesian product combination and a dissolve is performed to make the attribute value combinations unique for each Output region.


Selection files

A Selection file limits the set of regions and polygons that can be selected through the logical expressions. Since Query Regions allows the selection of features from many subclasses, building a query is also required when using selection files.

A Selection file can be used to define the selected features of one subclass while a logical expression can be used to define the selected features of another subclass. If the Selection file contains the desired set of features, use "reselect $poly" or "reselect $subclass" as the selection expression in the query.

Selection files are useful when multiple queries are to be performed on the same selected set of features. For example, all regions from the subclass landuse with a landuse attribute value of ‘residential’ can be selected and saved to a selection file. Multiple Query Regions operations can then be performed selecting subclass owner regions based on the selected features of subclass landuse.


Noncontiguous and contiguous regions

Query Regions is used to select features and partition them into homogeneous regions. The selected features define the spatial extent of the Output regions. The Region items with the Noncontiguous or Contiguous option define the granularity or resolution of the Output regions.

With the Noncontiguous option, the created regions may have several spatially separated components, as well as spatially connected components.

With Contiguous, the created regions have only one spatially connected component.

For example, you have the following coverage:

Run Query Regions with the Noncontiguous option, with the logical expression "Subset poly.type cn 'scrub", to create subclass 'scrub_non'. The result looks like this:

Run Query Regions with the Contiguous option, with the same logical expression, to create subclass 'scrub_con', and you get:

To convert from noncontiguous to contiguous regions, select all the regions in the noncontiguous subclass with the contiguous option specified.

To convert from contiguous to noncontiguous regions, select all the regions in the contiguous subclass with the noncontiguous option specified.


Notes for Region items

Region items lists all the items from the Input coverage's polygon attribute table (PAT) and region subclass PATs. Attribute value combinations for the selected items will be unique for each Output region. The items are written to the Output subclass PAT.

Unlike Dissolve which uses a single item, Query Regions will perform a final dissolve on the basis of the list of Region items. Query Regions inspects each Region item in the list, and regardless of whether the item is normal or redefined, returns all items associated with that item. For a redefined item, Query Regions will include the normal items that support it. For a normal item, all redefined items that overlap the normal item are included. The set of returned items become the output items in the Output subclass PAT. As a result, the output may have greater granularity than is indicated by the Region items alone.

If you select POLY.* or <SUBCLASS>.*, all items beyond the User-ID are used for the Region item.

When Region items are written to the subclass PAT, the prefix is stripped off, unless there is a conflict of names between two or more subclasses. In this case, the prefixes are maintained. If the name becomes too long and exceeds the limit of INFO file names, you will get the following error message:

"There is a name conflict between output items SUBCLASS1.VERYLONGNAME and SUBCLASS2.VERYLONGNAME that cannot be resolved by keeping the subclass prefix, because the resulting name would be too long. Query Regions not completed."

The maximum record length for an INFO table is 4096 bytes. If the number of output items exceeds this limit the following message is displayed:

"Unable to add item to region PAT. Maximum record length exceeded, possibly too many output items (n). Cannot create output subclass region PAT. Query Regions not completed."

To overcome this record length limit reduce the number of items for each input layer, or be more selective in the specification of the Region items by avoiding duplicate names in the Input coverage subclasses. Query Regions does not drop items with identical names, such as in the JOIN for a UNION, but instead provides a subclass pre-fix.

The maximum length of the Region items list is 254 characters. Exceeding this limit will cause Query Regions to stop processing and the following message will be displayed:

"Output items list was truncated, maximum length is 254 characters."

To avoid this limit, specify <SUBCLASS>.* to include all subclass attribute items beyond the <COVER>-ID.


Region components that do not share common boundaries; implies non-adjacency.


Region components that share common boundaries; implies adjacency.


The coverage with polygons or regions you want to query. This can be a single- or multi-layer coverage.


The coverage that will contain the new regions. This can be the same as the Input coverage, or a new coverage.


The region subclass you want to create. The name can be 1 to 13 characters long.

NOTE: If the subclass already exists, then the new data will be appended to its PAT.


 A Selection file identifies previously selected features of the Input coverage. This file is created in ARCPLOT and must already exist. You must also use the Query Builder to create a selection expression. See Query Regions toolhelp Selection files for more information and examples.


Choose the spatial relationships of your Output regions.

Noncontiguous – creates noncontiguous as well as contiguous regions in the Output subclass.

Contiguous – creates only contiguous regions in the Output subclass.


Choose the items you want to dissolve in the subclass you will create.


Check the box to show only the Region items you have selected.


The subclass items that will be dissolved.


Opens the Query Builder to build a selection expression.


Lists the selection expressions you built to query polygons and regions.


Raster to Geodatabase

Converts a raster to a Geodatabase raster.

The Input Raster can only be a file-based raster dataset. The Output raster can only be stored in a SDE Geodatabase, a relational database. You can spatially append the input raster to an existing raster dataset in the SDE geodatabase, provided the existing raster has the same cell size as the raster you want to append, to ensure the cells align perfectly. Also, the two raster datasets can overlap and their spatial reference definitions must match. If the spatial references do not match, the spatial reference definition of the existing raster dataset is maintained. As a second output option, you can add your raster as a stand-alone raster dataset to the SDE geodatabase.

To change Output settings click the Change Settings button.

Notes

When loading a raster dataset into a SDE geodatabase, it is stored as many small, spatially indexed BLOBs (Binary Large Objects) in multiple resolutions. When retrieved, these reduce the amount of data transferred between the client and the server, thus optimizing performance. Each time the raster is queried, only required tiles are streamed to the client, instead of the entire dataset. This makes it possible to store seamless raster datasets (10s to 100s of gigabytes) and serve them quickly to a client for display.

A set of geographically continuous raster datasets can be loaded into the geodatabase and managed in one of two ways: 1. as individual, seamless raster or 2. as a raster catalog. In the case of a single raster, many individual raster datasets are mosaiced into one seamless dataset that is one entity in the geodatabase. A single raster will always perform better than many raster datasets. So, to optimize performance, it is best to mosaic spatially continuous raster datasets. In the case of a raster catalog, each raster is an individual entity in the geodatabase; all raster datasets are connected by a raster catalog table.

When mosaicking rasters, set only the last raster to be mosaicked to build pyramids and statistics. Pyramids and statistics will then be built for the whole mosaicked ArcSDE raster after all rasters have been loaded.

As part of the raster loading process a raster table is created in the SDE geodatabase. A raster table is a business table with a raster column. At ArcGIS 8.1, one raster per raster table is supported.

The name for an output raster cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Related Topics


The name of an existing SDE Geodatabase to which you want to add the raster.


The name of the raster to be created.

The raster name cannot begin with a numeric character.


The settings that will be used during the conversion. Click the Change Settings… button to modify them.

Spatial reference: The output coordinate system determined from the input coverage feature class. The projection will be copied from the coverage, and the spatial domain calculated.

Keyword: A keyword that references database storage parameters on an SDE server. When loading data into an SDE Geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Storage: The options for building pyramids, calculating statistics, specifying a tile size and a compression type are all available.


Raster to Geodatabase Wizard

Converts a raster to a Geodatabase raster.

The Input Raster can only be a file-based raster dataset. The Output raster can only be stored in a SDE Geodatabase, a relational database. You can spatially append the input raster to an existing raster dataset in the SDE geodatabase, provided the existing raster has the same cell size as the raster you want to append, to ensure the cells align perfectly. Also, the two raster datasets can overlap and their spatial reference definitions must match. If the spatial references do not match, the spatial reference definition of the existing raster dataset is maintained. As a second output option, you can add your raster as a stand-alone raster dataset to the SDE geodatabase.

To change Output settings click the Change Settings button.

Notes

When loading a raster dataset into a SDE geodatabase, it is stored as many small, spatially indexed BLOBs (Binary Large Objects) in multiple resolutions. When retrieved, these reduce the amount of data transferred between the client and the server, thus optimizing performance. Each time the raster is queried, only required tiles are streamed to the client, instead of the entire dataset. This makes it possible to store seamless raster datasets (10s to 100s of gigabytes) and serve them quickly to a client for display.

A set of geographically continuous raster datasets can be loaded into the geodatabase and managed in one of two ways: 1. as individual, seamless raster or 2. as a raster catalog. In the case of a single raster, many individual raster datasets are mosaiced into one seamless dataset that is one entity in the geodatabase. A single raster will always perform better than many raster datasets. So, to optimize performance, it is best to mosaic spatially continuous raster datasets. In the case of a raster catalog, each raster is an individual entity in the geodatabase; all raster datasets are connected by a raster catalog table.

When mosaicking rasters, set only the last raster to be mosaicked to build pyramids and statistics. Pyramids and statistics will then be built for the whole mosaicked ArcSDE raster after all rasters have been loaded.

As part of the raster loading process a raster table is created in the SDE geodatabase. A raster table is a business table with a raster column. At ArcGIS 8.1, one raster per raster table is supported.

Related Topics


Output ArcSDE Geodatabase

The output raster must be stored in an ArcSDE geodatabase; rasters cannot be loaded and stored in a personal geodatabase.

There are four options to load a raster into an ArcSDE geodatabase using the wizard:

Create a new ArcSDE raster adds the input raster as a standalone dataset to the ArcSDE geodatabase.

Modify an existing ArcSDE raster appends the input raster to an existing ArcSDE raster or replaces an existing ArcSDE raster with the input raster. The existing ArcSDE raster must have a spatial reference for the appending operation. The default option is to append the input raster to the existing ArcSDE raster, but this can be modified on Storage Properties.

Create a new ArcSDE raster catalog creates a new raster catalog in the ArcSDE geodatabase and inserts the input raster to the raster catalog. The new raster catalog will inherit the spatial reference of the input raster or it can be specified at loading.

Modify an existing ArcSDE raster catalog inserts the input raster to the existing raster catalog or if an existing raster in the raster catalog is selected as output raster, the existing raster in the raster catalog will be modified by appending or replacing.

The name for an output raster or raster catalog cannot begin with a numeric character. If this occurs the leading numeric character(s) will be dropped.


Storage properties

   Update Mode

   Statistics Option

   Compression

   Tile size

   Pyramids options


Configuration keywork

The configuration keyword specifies the table spaces in which the data and indices will be stored, it is defined in the dbtune.ini file. To improve performance it is best to store the indices and data in different table spaces on different physical devices.

For more information on creating SDE keywords, see the SDE Administration documentation.


Current spatial reference

The spatial reference specified in the output settings will be assigned to the ouput raster.

Note: Unlike feature class to geodatabase conversion, if the input and output coordinate systems are different, the raster will not be projected.


The Update mode is automatically enabled when the output is an existing raster dataset. Disable this option to overwrite the output raster dataset.


The Statistics option enables you to build statistics for the output raster dataset. Statistics are required for your raster dataset in order to perform certain tasks in ArcMap or ArcCatalog, such as applying a contrast stretch or classifying your data. It is not essential to build statistics at this point, as they are calculated the first time they are needed, if they have not already been calculated. It is, however, recommended that you calculate your raster datasets before using them. The default display of your raster in ArcMap or ArcCatalog will be improved if statistics have already been calculated, because a standard deviation stretch is applied, if statistics are present. In many cases, the default display is improved, because, rather than the raster layer being added with no stretch (the default if statistics have not been calculate), which sometimes uses only a portion of the bit depth, the raster is added with a two standard deviation stretch, which allows more of the bit depth to be used and therefore the raster is brighter and has more contrast.

For more information on the default display of rasters, see “Initial display properties”.  For more information on improving raster display speed, see “Improving raster display speed”.  Both of these topics can be found in the raster section of Desktop Help.


Data Compression compresses blocks of data before storing the raster in the geodatabase. The compression used is LZ77, a lossless compression, that maintains all raster cell values. It is the same compression method used by the PNG image format and by ZIP compression. The amount of compression will depend upon the data. The more homogeneous the data, the higher the compression ratio.

The primary benefit of data compressing is that it requires less storage space. An added benefit may be improved performance of up 20 percent because smaller packets of data are being moved across the network. Compression may also reduce raster load times by up to 50 percent by reducing disk IO.


The tile size lets you control the number of pixels that are stored in each BLOB, and therefore lets you control the size of the BLOB. It is specified as a number of pixels in X and Y. A good guideline to use is to use a tile size that is ¼ the size of the data you plan to serve. For example, if you plan to serve data to a client who’s display window will normally be 500x500 screen pixels, a good tile size would be 250x250 pixels.


Pyramids are reduced resolution representations of your dataset, which are used to improve performance. Pyramids can speed up display of raster data by retrieving only the data at a specified resolution that is required for the display. Pyramids are created by resampling the original data. The resampling methods instruct the server how to resample the data to build the pyramids.

If the Do not build pyramids option is selected, pyramids will not be created with the ouput raster. Not building pyramids saves storage space but will lead to slower display speed, especially for a larger raster dataset.

If the Build pyramids option is selected, pyramids will be created and are used  to improve raster display performace as described above.

- Use Nearest neighbor for nominal data or raster datasets with colormaps, such as land use data, scanned maps and pseudocolor images.

- Use Bilinear interpolation or cubic convolution for continuous data, such as satellite imagery or aerial photography.


The greater the bit depth, i.e., more bits per pixel, the more colors are available and the more accurate the raster's color representation.


Raster to MrSID

Converts a raster dataset into a MrSID encoded image.

Notes

A license is required in order to compress raster datasets larger than 50 MB of data or mosaic multiple raster datasets into a single MrSID image.

A licensed version of the tool may convert up to 500 MB of data into a single MrSID file.

The following pixel types are supported for Multi and Single-band rasters:

Multi-band rasters:	PT_U1, PT_U2, PT_U4, and PT_UCHAR

Single-band rasters:	PT_U1, PT_U2, PT_U4, and PT_UCHAR, PT_FLOAT, and PT_USHORT

MrSID and Georeferencing

MrSID World Files

Mosaics with an Inconsistent Pixel Grid

Realignment to a Consistent Pixel Grid

Correcting a Grid Misalignment

Related Topics


The Input Raster can be any raster file in a format that ArcGIS supports. The name can be entered by typing the path, browsing, dragging from Explorer, or dragging from ArcCatalog.


The list of raster datasets that will be massed into a single MrSID mosaic image. Add a raster to the list by entering a new raster into the input box above. The total combined size of all rasters must not exceed 500 MB.


Click to delete the raster selected in the mosaic list.


Select if you want to convert Nodata values contained by the input rasters to a specific RGB value in the output MrSID image.


Enter the combined Red, Green and Blue values that will represent areas of Nodata in the output image.


Enter the combined Red, Green and Blue values that will represent missing and/or background areas in the output image. You may also use the adjacent color-picker to select the RGB value.


Click to open a color-picker. Choose the color you want for missing and/or background areas in the output image.


The band order that will be used when creating the new MrSID file. Choose the band order you want or accept the default order.


The MrSID image you will create.


MrSID and Georeferencing

One of the key features of MrSID is its ability to mosaic multiple image tiles into a single image. For this to be possible, the imagery being encoded must have associated georeferencing data. This data can either be stored in the image file itself, as with LAN imagery, or it can be contained in a separate ASCII file, generally referred to as a world file. This file must have the same name as the image file, with a .tfw (for TIFF imagery) or .hdr (for BIL, BIP, or BSQ imagery) extension.


MrSID World Files

When a MrSID file is created from a single image or mosaic of images in one of the georeferenced formats supported by MrSID Encoder, a MrSID world file is created. This file is created in the same directory as the output image file, and has the same name as the MrSID file, with a . sdw extension.

This file holds the georeferencing information given to the encoder by the original georeferencing information contained in the metadata for the source imagery.

MrSID world files are in the same format as TIFF world files.


TIFF World Files

TIFF world files contain the same information as .hdr files, but are arranged differently. An example is shown below:

0.20000000000000

0.00000000000000

0.00000000000000

-0.20000000000000

3615780.10000000000000

2127219.90200000000000

The first line represents the dimension of a pixel in map units in X direction.

The second and third lines represent rotation terms. Data in these two lines is ignored.

The fourth line represents the dimension of a pixel in map units in Y direction.

The fifth line represents the X coordinates of the center of the upper-left pixel.

The sixth line represents the Y coordinates of the center of the upper-left pixel.


Mosaics with an Inconsistent Pixel Grid

When MrSID creates a single image mosaic from a set of georeferenced raster images, the map scale of all the images must be the same. If the images do not have the same map scale, an error is returned.

Since MrSID is a raster format, the input map scale is considered a grid of pixels. The orientation of the grid is based on that of the upper left-hand corner image in the mosaic.

When MrSID creates a mosaic of images, it places individual images onto a pixel grid. In most cases, images used in a single mosaic have been projected to the same grid. When these images are combined into a single MrSID image, all the images align properly and the mosaic is seamless.

If any of the images used in a mosaic have been projected to an alternate pixel grid, MrSID must realign these images to the grid set in place by the upper left-hand corner image.


Realignment to a Consistent Pixel Grid

When MrSID creates a single image from a set of georeferenced raster images, the images are aligned to a consistent pixel grid. Since MrSID is a raster image format, and the MrSID program cannot interpolate input data to a new pixel grid, MrSID must compensate for this misalignment. Using the nearest neighbor method, the misaligned image in the mosaic are shifted to align with the grid established by the upper left-hand corner image.

Though the image is shifted as slightly as possible and never more than 1/2 a pixel in any direction this shift may be noticeable when the MrSID image is compared to the source data, or when vector overlays created for the source data are used with the MrSID image.

This potential 1/2-pixel shift falls within map accuracy standards when working with USGS imagery.


Correcting a Grid Misalignment

In some cases a user may find it desirable to correct a pixel-shift and re-encode the data. Two options are available.

1. Reproject the source data using a GIS imaging program, or

2. Edit the world or header files using any ASCII text editor.

The first option is the most accurate and may be implemented at the user's discretion. The second option is demonstrated here.

Following are samples of two TIFF world files which have a corresponding map scale, but which align to separate pixel grids:

image1. tfw:

1.000

0.000

0.000

-1.000

624.500

100.000

image2. tfw:

1.000

0.000

0.000

-1.000

324.500

306.600

For these two images to be aligned to a single grid, the X and Y coordinates of each image must align to the specified pixel dimension in this case, 1.000 by 1.000. The shift between the two images is caused by the .6-pixel change in the second
image's Y-coordinate.

To align these two images to the same grid, the Y coordinates must be brought into alignment. This can be done by:

Changing the Y-coordinate of image1. tfw from 100.000 to 100.600, thus aligning it with the Y-coordinate of image2. tfw.

Changing the Y-coordinate of image2. tfw from 306.600 to 306.000, thus aligning it with the y-coordinate of image1. tfw.

Changing the Y-coordinates of both images to 100.300 and 306.300, respectively, thus aligning both images to an average pixel grid.

When compared to the source data or overlaid by vector graphics previously aligned to the source data mosaics corrected in this way will still display a pixel shift. The degree of the shift depends on the degree of grid realignment required. The only way to create a precisely accurate mosaic from imagery aligned to multiple grids is to use method #1 described above, reprojecting the source data to a consistent grid.


MrSID is based on LizardTech's Multiresolution Seamless Image Database(MrSID) technology created at Los Alamos National Laboratory under license from the Regents of the University of California. MrSID and DjVu are registered trademarks of LizardTech, Inc.  Unauthorized use prohibited.  All other trademarks are the property of their respective owners.


A raster dataset’s size is calculated by multiplying the image width, the image height, and the number of bands contained in the raster. For example an 8 bit RGB TIFF image that is 1000 pixels by 1000 pixels is 2.86 megabytes ((1000 x 1000 x 3)/1048576 = 2.86 MB.

Note: Images with a Color Lookup Table (CLUT) will be treated as single band images.  A CLUT image will be treated as 1 byte per sample unless it has greater than 256 CLUT entries.  If greater than 256 it will be treated as 2 bytes per sample.

Note:  Images less than 8 bits are considered as 1 byte per sample.


The target encoding ratio to use during the image compression process. As a starting point for most imagery, we recommend 10 for grayscale imagery or 20 for RGB.


Region to Polygon Coverage

Creates polygons from a region subclass, and creates a table with data on overlapping regions.

All items in the region Subclass polygon attribute table (PAT) are maintained in the Output coverage PAT. The Output coverage PAT contains only the attributes of the first region associated with each polygon. Values of 0 indicate void areas in which the Subclass does not exist. The attributes of the second to the Nth regions associated with each polygon are stored in the Output table.

If only one region is associated with each polygon (a planar region region subclass), then the Output table does not need to be specified. But an Output table must be specified when using non-planar region subclasses. The following message will be displayed when the Subclass has non-planar regions:

"Subclass contains overlapping regions, output table required."

Notes

The polygon User-IDs of the Output coverage will be altered.

Use the Output table to relate the Output coverage polygons to the Input coverage region subclass.

Example

Related Topics


The coverage with regions you want to convert to polygons.


The region subclass in the Input coverage you want to convert to a polygon coverage.


The coverage you will create.


The table listing the association between the polygons of the Output coverage and the input region Subclass.


Example

Input

The region coverage Regioncov has one region subclass, HOUSE, with three regions. The first (1) and second (2) regions consist of one polygon each. The third (3) region overlaps the first two regions and has two polygons.

Listing of REGIONCOV.PATHOUSE:

Record   AREA  PERIMETER  HOUSE#  HOUSE-ID
1      10.946     13.268       1         1
2       5.259      9.574       2         2
3      16.205     16.685       3         3

Output

The output coverage Polycov has two polygons. Their associations to the input region subclass HOUSE are listed in the Output table HOUSETABLE.

Listing of POLYCOV.PAT:

Record    AREA PERIMETER POLYCOV# POLYCOV-ID POLY#  SUBCLASS SUBCLASS#
1      -16.205    16.685        1          0     1               0
2       10.946    13.268        2          1     2  HOUSE        1
3        5.259     9.574        3          2     3  HOUSE        2

HOUSETABLE lists the associations between the Output coverage polygons and the Input coverage region subclass:

Record   POLY#  SUBCLASS#
1            2      1
2            2      3
3            3      2
4            3      3


Renumber Nodes

Updates arc-node topology by renumbering nodes for coverage arcs and identifies arcs that share the same node locations. The tool renumbers the internal node numbers for each arc, assigns the same node number for arcs which share a common node location, and updates the FNODE# and TNODE# items in the arc attribute table (AAT) when it exists.

For ArcInfo operations, it is desirable for the internal numbers of all nodes to be sequentially numbered and to have nonzero values. Also, if two or more nodes occur at the same x,y location, they should be identified by the same internal node numbers. Since some tools do not establish or reset node numbers, Renumber Nodes can be used after the Generate to Coverage Wizard and the Select, Eliminate and Dissolve tools. The tool is also used to define the connectivity of arcs for network analysis, to make node error verification and correction easier, and to prepare a coverage for the Coverage to DLG tool.

Notes

Use caution with coverages containing coincident and duplicate nodes.

Using From-node elevation item and To-node elevation item can create more nodes than are actually present. To delete unwanted nodes, run the tool again without specifying these items.

If the Input coverage has an node attribute table (NAT), Renumber Nodes does the same thing as Build with the Node option.

Related Topics


The coverage whose nodes you want to renumber.


Choose the item that defines the elevation of the from-node of each arc. This ensures that coincident nodes and lines at different planes are maintained.


Choose the item that defines the elevation of the to-node of each arc. This ensures that coincident nodes and lines at different planes are maintained.


Use caution with coverages containing coincident and duplicate nodes

Renumber Nodes dissolves coincident and duplicate nodes into single nodes. For example, while modelling freeway ramps you may run into situations having coincident arcs in different planes with multiple nodes sharing the same x,y coordinates. Running the Build tool with the Line option will preserve this topology. However, Renumber Nodes will collapse the coincident nodes into single nodes and destroy this topology.

To retain coincident nodes at different "elevations" on a coverage that describes an underpass/overpass situation, two items to represent From node elevation item and To node elevation item must be present in the AAT and specified in the tool.

The term "elevation" as referred here is relative. It does not have to be the real world or 3D elevation. Rather, it signifies the elevation of the ends of an arc relative to another that it may meet or cross. Its primary use is in building the arc-node topology to reflect transportation network situations such as an overpass/underpass. As an example, consider the following:

            Z
           o
           |
           |Y

  o--------o-------o
  A      B |       C
           |
           o
            X

We can model an underpass/overpass situation by giving one set of node elevation values to arcs AB, BC, while arcs XY, YZ could share a different set of node elevation values. Using Renumber Nodes with the elevation arguments will actually retain two distinct nodes at the cross point. As in real life, this will prevent a path between nodes A and Z. Many transportation data vendors like NAVTECH make such information available in their data products. Besides these transportation applications, ArcInfo NETWORK's TRACE can also use this information for utility networks to perform upstream/downstream traces.

The "elevation" values for all nodes having no conflict could be set to zero. Only in cases where there are multiple nodes sharing the same x,y coordinates, the elevation values would be looked up to determine whether they are in the same plane and dissolved or in different planes and retained.


Import SDTS Wizard

Creates ArcInfo coverages or grids from a SDTS Topological Vector Profile (TVP), Raster Profile or Point Profile transfer.

Notes

The wizard can read the U.S. Bureau of the Census TIGER and U.S. Geological Survey DLG-3 data in SDTS format.

Complex spatial object modules are converted to either regions or route and sections depending on the spatial object type.

The raster profile provides a very flexible way to encode raster data. In a raster transfer there should be one RSDF module, one LDEF module and one or more cell modules. Each record in the RSDF module denotes one raster object. Each raster object can have multiple layers. Each layer will be encoded as one record in the LDEF module. The actual grid data is stored in the cell module which is referenced by the layer record. A typical USGS DEM data set will have one RSDF record, one LDEF record and one cell file. A typical ERDAS image data set will have one RSDF record, multiple LDEF records and one or more cell files.

Supported file extension

Related Topics


Layer information

The SDTS spatial data model can be made up of more than one spatial object (referred to as aggregated spatial objects), which can be thought of as data layers in the Point or Topological Vector profiles. A Raster Profile may contain multiple raster object record numbers, which are contained in the RSDF module of a Raster Profile data set. Multiple layers in a TVP or Point Profile transfer must be converted into separate coverages, while multiple raster object record numbers must be converted into separate grids.

When you convert an aggregated spatial object or data layer, polygon and line topology are generated. Complex spatial object modules are converted to either regions or route and sections depending on the spatial object type. Related attribute tables are written to the output coverage.

The following list explains the codes given in the Layer information or Raster Object information list. The Layer information list gives the number of various feature types in the layer selected in the Layers list. Raster Profile transfers contain raster objects and do not contain multiple feature types.

(nn = layer number)

Vector modules                Theme

Point-Node

NP – Point                    NPnn
NL - Label point              NLnn
NE - Entity point             NEnn
NA - Area point               NAnn
NO - Node, planar             NOnn

Line

LE - Complete chain           LEnn
Polygon
PC - GT-polygon chains        PCnn
PW - Universe poly chains     PWnn
PV - Void polygon             PVnn
PX - Void polygon chains      PXnn

Point modules

NE - Entity point             Nenn
NP – Point                    NPnn
NL – Label point              NLnn


Module information

SDTS transfer files are like ArcInfo coverages, consisting of modules, which are physical files. Each module, formatted as specified by Part 3 of the SDTS standard and ISO 8211, consists of one or more records. Each record consists of one or more fields. Each field consists of one or more subfields. The individual data items are carried by the subfields. The modules come in three groupings, Global, Data Quality, and Spatial Objects. The Global Information Modules define global parameters for interpreting the data transfer. The Data Quality modules contain information on the quality of the transferred data. Spatial Object modules include the locational, topologic, and attribute information for the data set. Not all files will be included in all data sets; see Part 4 of the SDTS standard for a complete list of the required modules.

Choose one of the modules from the Modules list in order to display its contents. Module names that end with numbers, such as TR01LE01.DDF, provide specific feature information for each layer. In this example, LE01 refers to complete chain polygons in layer 01. Displaying the contents of a module can take several minutes or even longer depending on the size of the module and the number of records it contains.

(nn = layer number)

SDTS Modules

Module     Module Type      Primary Field Name           Mnemonic

Global     Identification                                IDEN

           Catalog           Directory                   CATD
                             Cross-Reference             CATX
                             Spatial Domain              CATS

           Spatial-          Internal                    IREF
           Reference         Raster Definition           RSDF
                             Layer Definition            LDEF
                             External                    XREF
                             Spatial Domain              SPDM

           Data-             Definition                  DDDF
           Dictionary        Domain                      DDOM
                             Schema                      DDSH

           Security                                      SCUR

           Transfer Stats                                STAT

Data-                        Lineage                     DQHL
Quality                      Positional Accuracy         DQPA
                             Attribute Accuracy          DQAA
                             Logical Consistency         DQLC
                             Completeness                DQCG

Spatial-   Composite                                     FFnn
Objects

Vector     Point-Node        NP – Point                  NPnn
                             NL - Label point            NLnn
                             NE - Entity point           NEnn
                             NA - Area point             NAnn
                             NO - Node, planar           NOnn

           Line              LE - Complete chain Poly    LEnn
                             PC - GT-polygon chains      PCnn
                             PW - Universe poly chains   PWnn
                             PV - Void polygon           PVnn
                             PX - Void polygon chains    PXnn

Point                        NE - Entity point           Nenn
                             NP – Point                  NPnn
                             NL – Label point            NLnn

Raster                       Registration                RGIS
                             Color index                 CLRX
                             Raster definition           RSDF
                             Layer defintion             LDEF
                             Cell                        Cnnn

Attribute                    Primary                     Annn
                             Secondary                   Bnnn

For more information on layers, click [image].


Related tables

Related attribute tables are written to the output coverage. The relate environment is stored in Line coverage.REL and/or Point coverage.REL. Grids created from a raster profile transfer have no predefined relates.

An additional cross reference table Line coverage.XREF, or Point coverage.XREF for point profile data, will be written to store both the from and to table information for all related attribute tables. A cross reference table is not created for raster profile datasets.

Use the Relate Manger to restore and list the relates.


Input SDTS transfer

The Input SDTS transfer prefix is a four-character prefix common to all files in the SDTS transfer. Use the prefix browser if you are unfamiliar with the prefix of your dataset.

Modules - SDTS transfer files are like ArcInfo coverages, consisting of physical files called modules. Modules are specific to various aspects of the SDTS data set and can be viewed separately. For example, the IDEN module contains the identification information for the input SDTS transfer. Refer to the Help for the Modules panel if you want further information regarding specific modules.

Data dictionary - A data dictionary is a set of files containing global information about more than one transfer. It can be external from the transfer but must be under a directory called 'masterdd' located at the same directory level as the transfer directory so that output coverages will share the same data dictionary information without duplication. Using a data dictionary is recommended as it will create INFO tables containing the explanations for codes and abbreviations used in the new coverage.


The Spatial Data Transfer Standard (SDTS) is a data exchange format for transfering different databases between dissimilar computing systems, preserving meaning and minimizing the amount of external information needed to describe the data. In the future, all Federal digital map data will be made available upon request in SDTS format. SDTS is documented in FIPS publication 173 available from the U.S. Department of Commerce.


Convert void and fill values

In the Raster profile, NULL values are defined in two general categories:

A. Undefined, not relevant (Fill)

B. Relevant, but unknown or missing (Void)

These categories are specified with specific values that vary depending on the type of data contained in the SDTS raster transfer. For example, the values for DEMs are -32767 for void areas and -32766 for fill areas. These values are at the extreme negative end of the allowable data range for DEMs. DOQs on the other hand, have an allowable data range of 0-255 with assigned null and fill values of 0 or 128. DRGs have an allowable data range of 0-255 and have no void or fill areas because it's a scanned image.

Consult the USGS SDTS raster standards at http://mcmcweb.er.usgs.gov/sdts/standard.html to determine the void and fill values of the raster data type you are converting.

You may want to convert these values to Nodata if these areas are not useful to you. If this is the case, simply check the box to convert. If these areas are of interest to you and/or you want to convert the new grid back to SDTS at some point in the future, then you may want to uncheck the option to convert these values and preserve them in the new grid.


SDTS Raster To Grid

Creates ArcInfo grid from a SDTS Raster Profile data set.

Notes

SDTS is a large standard composed of smaller, more limited subsets that are Federally approved as part of the SDTS FIPS 173 standard. These subsets are called profiles. This tool can read the U.S. Geological Survey DEM raster data in SDTS format and the SDTS Point to Coverage tool can read National Geodetic Survey geodetic control point data in SDTS format.

The raster profile provides a very flexible way to encode raster data. In a raster transfer there should be one RSDF module, one LDEF module and one or more cell modules. Each record in the RSDF module denotes one raster object. Each raster object can have multiple layers. Each layer will be encoded as one record in the LDEF module. The actual grid data is stored in the cell module which is referenced by the layer record. A typical USGS DEM data set will have one RSDF record, one LDEF record and one cell file. A typical ERDAS image data set will have one RSDF record, multiple LDEF records and one or more cell files.

The SDTS spatial data model can be made up of more than one spatial object (referred to as aggregated spatial objects), which can be thought of as data layers in the Point or Topological Vector profiles. A Raster Profile may contain multiple raster object record numbers, which are contained in the RSDF module of a Raster Profile data set. Multiple raster object record numbers must be converted into separate grids. This is done by converting each raster object record number (Record no), one at a time, into an Output grid.

If the Convert values option is to convert Void and fill values to Nodata in the Output grid. If the Convert values option is not used, he void and fill values will be maintained in the Output grid.

A data dictionary is a set of files containing global information about more than one transfer. It can be external from the transfer but must be under a directory called 'masterdd' located at the same directory level as the transfer directory so that output coverages will share the same data dictionary information without duplication. Using a data dictionary is recommended as it will create INFO tables containing the explanations for codes and abbreviations used in the new coverage.

In order for this tool to run, the environment variable TEMP must not contain spaces. The tool will produce a relevant message if spaces are encountered in the TEMP variable.

Example of a typical USGS Raster Profile data set

Supported file extension

Related Topics


A four-character prefix common to all files in the SDTS transfer.


The raster object record number in the RSDF module of a Raster Profile data set. There may be multiple raster object record numbers in a single transfer. By default the first number encountered is the only one that will be converted.


Convert void and fill values in the raster transfer to Nodata in the Output grid.


Use Data Dictionary

Checked – Data Dictionary modules (i.e., DDDF and DDOM) will be used in conversion to create INFO tables containing the explanations for codes and abbreviations used in the new coverage.

Unchecked - Data Dictionary modules will not be used.


The following list is a typical USGS Raster Profile data set:

1013CATD.DDF	1013CATS.DDF	1013CEL0.DDF
1013DDDF.DDF	1013DDOM.DDF	1013DDSH.DDF
1013DQAA.DDF	1013DQCG.DDF	1013DQHL.DDF
1013DQLC.DDF	1013DQPA.DDF	1013IDEN.DDF
1013IREF.DDF	1013LDEF.DDF	1013RSDF.DDF
1013SPDM.DDF	1013STAT.DDF	1013XREF.DDF


Void and Fill Values

In the Raster profile, NULL values are defined in two general categories:
A. Undefined, not relevant (Fill)
B. Relevant, but unknown or missing (Void)

These categories are specified with specific values that vary depending on the type of data contained in the SDTS raster transfer. For example, the values for DEMs are -32767 for void areas and -32766 for fill areas. These values are at the extreme negative end of the allowable data range for DEMs. DOQs on the other hand have an allowable data range of 0-255 with assigned null and fill values of 0 or 128. DRGs have an allowable data range of 0-255 and have no void or fill areas because it's a scanned image.

Consult the USGS SDTS raster standards at http://mcmcweb.er.usgs.gov/sdts/standard.html to determine the void and fill values of the raster data type you are converting.


SDTS Point To Coverage

Converts SDTS Point data to an ArcInfo point coverage.

Notes

SDTS is a large standard composed of smaller, more limited subsets that are Federally approved as part of the SDTS FIPS 173 standard. These subsets are called profiles. This tool can read the National Geodetic Survey geodetic control point data and the SDTS Raster to Grid tool can read U.S. Geological Survey DEM raster data in SDTS format.

Point topology is generated for Point Profile data.

The SDTS spatial data model can be made up of more than one spatial object (referred to as aggregated spatial objects), which can be thought of as data layers in the Point or Topological Vector profiles. Multiple layers in a TVP or Point Profile transfer must be converted into separate coverages.  This is done by converting each Layer, one at a time, into an Output coverage.

A data dictionary is a set of files containing global information about more than one transfer. It can be external from the transfer but must be under a directory called 'masterdd' located at the same directory level as the transfer directory so that output coverages will share the same data dictionary information without duplication. Using a data dictionary is recommended as it will create INFO tables containing the explanations for codes and abbreviations used in the new coverage.

In order for this tool to run, the environment variable TEMP must not contain spaces. The tool will produce a relevant message if spaces are encountered in the TEMP variable.

Related attribute tables are written to the output data set.

Example of a typical National Geodetic Survey Point Profile data set

Supported file extension

Related Topics


The name of an aggregated spatial object that represents a single data layer in a Point Profile transfer. There may be multiple layers in a single transfer. By default the first layer encountered is the only one that will be converted.


The following list is a typical National Geodetic Survey Point Profile data set:

PP01ACTL.DDF	PP01ASUP.DDF	PP01DDSH.DDF
PP01DQPA.DDF	PP01STAT.DDF	PP01ADSC.DDF
PP01CATD.DDF	PP01DQAA.DDF	PP01IDEN.DDF
PP01XREF.DDF	PP01AGEO.DDF	PP01CATS.DDF
PP01DQCG.DDF	PP01IREF.DDF	PP01AHIS.DDF
PP01DDDF.DDF	PP01DQHL.DDF	PP01NE01.DDF
PP01AREF.DDF	PP01DDOM.DDF	PP01DQLC.DDF
PP01SPDM.DDF


Select

Extracts selected features from an Input coverage and stores them in the Output coverage. Features are selected for extraction based on logical expressions or applying the criteria contained in a Selection file. Any item, including redefined items, in the specified feature attribute table of the Input coverage can be used.

Select discovers the feature classes in the Input coverage and offers those available for selection:

Poly – polygons are reselected using PAT item values. For more on Poly, click [image].

Line – arcs are reselected using AAT item values.

Point – points are reselected using PAT item values.

Anno.<subclass> – annotation from the specified subclass is reselected using TAT subclass item values.

Route.<subclass> – routes from the specified subclass are reselected using RAT subclass item values.

Section.<subclass> – sections from the specified subclass are reselected using SEC subclass item values.

Region.<subclass> – regions from the specified subclass are reselected using the region PAT subclass item values. For more on regions, click [image].

Notes

When using the same Input coverage and Output coverage for feature classes Anno, Section, Route, or Region, the Output feature class subclass name must be different from the Input feature class subclass name.

The same subclass names may be specified when the Output coverage is not the same as the Input coverage.

Use of indexed items in the Query Builder can speed up the logical selection process. You can use the ArcCatalog to create an item index.

There is a limit of 100 Input coverages that can be specified in Batch mode.

Make sure all the features are labeled correctly by running ARC LABELERRORS before running the Select tool.

Data model content inherited by the output

How to build a query

Related Topics


Feature class Poly

The number of polygons in the Output coverage might not match the number of records selected. Unselected polygons that are completely surrounded by selected polygons are retained in the Output coverage because they are islands in a selected polygon; however, they will have a User-ID of 0 and no attributes.

If the universe polygon is included in the selected set, the Select tool does not drop polygons which are part of the boundary of the universe polygon. The polygons remain, and their attributes will be changed to zero.

Select will rebuild an existing AAT and NAT for the arcs in the Output coverage. Each output arc will have the same User-ID and AAT item values as in the Input coverage.


Feature class Region.<subclass>

Not only are the polygons associated with the selected regions transferred to the new coverage, but also other features associated with these polygons (arcs, nodes, routes), including their associated attribute tables. The tool will rebuild an existing AAT and NAT for the arcs in the Output coverage. Each output arc will have the same User-ID and AAT item values as in the Input coverage.


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Feature attribute table items

Tics

Annotation (only specified annotation is copied if it is the Input feature class)

Node attribute table for any line features

Projection file

Regions (with Poly or Region as the Input feature class)

Route systems (with Arc or Route as the Input feature class) ADD and TRN files - but they need to be rebuilt with the commands ADDRESSBUILD and TURNIMPEDANCE


 A Selection file stores the specifications of the selection criteria to be applied against specific coverages and INFO tables. It does not store the actual selected features or records, only the selection methods. Selection files are created with the WRITESELECT command in ARCPLOT.


The universe polygon is the first record in a polygon attribute table. It represents the area beyond the outer boundary of the coverage. It’s the only polygon that never has a label point, and so has a User-ID value of 0. Its area equals the negative sum of all the polygons in the coverage. Also referred to as the external polygon.


The coverage whose features will be selected.


The coverage you will create.


The feature classes available for selecting:

Poly – polygons

Line – arcs

Point – points

Anno.<subclass> – annotation from a specified subclass

Route.<subclass> – routes from a specified subclass

Section.<subclass> – sections from a specified subclass

Region.<subclass> – regions from a specified subclass


The feature class in the Output coverage must be the same as that of the Input feature class, with this exception:

When Input feature class is an Anno, Route, Section or Region subclass, and the Output coverage is the same as the Input coverage, the Output feature class must have a different subclass name.


Choose how you want to select features.

Build a query – uses the Query Builder to create one or more logical expressions to select the features you want.

Selection file – uses a pre-existing file that identifies the features you want to select.


Lists the selection expressions you built with the Query Builder.


Opens the Query Builder to build or edit the logical expressions.


Shapefile to AGF

Converts a shapefile into an Atlas Geo File (AGF) for use with Atlas GIS.

This tool does not support remote processing using a Geoprocessing Server. The tool is always run with a local processing state.

Notes

You must know the projection of the shapefile or you will have to specify USER, USER_2, USER_4 or USER_6 projections. Labels for each polyline are calculated by finding the longest segment of the first line of the polyline and using the midpoint of that segment. The angle of that segment is used for the angle of the label.

Labels for each region are calculated by using the centroid of the first polygon of a region. The angle of the label is zero. The tool will skip any shape feature that has more than 4090 vertices. The conversion process will continue, but before you open the resulting AGF file in Atlas, please run the GEOFIX program found in the /agisw subdirectory on the AGF file.

Once you open the AGF file in Atlas, the index files will be rebuilt, and the AGF file may then be used normally.

Related Topics


The name of the shape file to use for the conversion. You must have SHP, SHX and DBF files to do the conversion.


The name of the ATLAS AGF file to create. An AGF and AIF file will be created.


The name of the layer that will be created on the AGF file. This is limited to sixteen characters and must not have any blanks. Note:  this parameter is case-sensitive.


The projection or coordinate system the shapefile currently is in.


The name of the item from the shapefile that will be used as the _ID field on the AGF file.


The name of the item from the shapefile that will be used as the _NAME field on the AGF file. This parameter is optional.


The name of the item from the shapefile that will be used as the _NAME2 field on the AGF file. This parameter is optional.


Shapefile to Coverage

Converts shapefile spatial and attribute data to a coverage.

Notes

If you want to create an output subclass, such as regions or routes, you must first specify the feature type followed by the subclass name, separated by a period. For example, to create a region subclass called ‘test’ when converting a polygon shapefile, the Output feature class would be called ‘Region.test’.

By default, a shapefile’s attributes, contained in the dBASE (.dbf) file, are converted using the same mapping as the dBASE to INFO tool.To set up custom mapping of the dBASE field names to INFO item names, use the Define mapping option.

There are a number of issues that should be taken into account when converting between different spatial data formats when converting between coverages and shapefiles.  Polygons in shapefiles are discrete and do not share geometry between features.  Coverage polygons do share geometry between features.

When a shapefile polygon layer is converted to a polygon coverage, the data must be processed by the conversion to create correct topology.  A Clean is used to eliminate duplicate arcs between the polygons.  Since shapefiles do not maintain a label point for the polygons, new ones have to be generated.  When a polygon coverage is created Shapefile to Coverage creates the label points.  Label points are not created when the output is a region subclass.  The precision of the resulting coverage is set by the precision option found in the ArcToolbox Options dialog.  By default the coverage creation precision is set to single.  The fuzzy tolerance used by Clean depends on the precision and the longest dimension of the output coverage boundary.

Default data type conversion from INFO to dBASE

Translation summary of shape types

Related Topics


Default data type conversion from INFO to dBASE

ArcInfo data types       dBASE data types

Type Width Output Dec
 C    n      -     -     Character <expC>(n)
 D    -      -     -     Date      <expD>
 B    2      -     -     Numeric   <expN>(6,0)
 B    4      -     -     Numeric   <expN>(11,0)
 I    n      -     -     Numeric   <expN>(n,0)
 N    n      -     m     Numeric   <expN>(n,m)
 F    -      n     m     Numeric   <expN>(n,m)


Translation summary of shape types

Shapefile     Type   Output subclass  Output  Attributes in
Point        Type 1  Will be ignored  Points      PAT
Line         Type 3  None entered     Lines       AAT
Line         Type 3  Entered          Routes    subclassRAT
Polygon      Type 5  None entered     Polygons    PAT
Polygon      Type 5  Entered          Regions   subclassPAT
Multi Point  Type 8  Will be ignored  Points      PAT


 The shapefile you want to convert.


The coverage you will create.


The feature subclass you want to create. You can create a subclass for polygon and line features.

Note: To create a region or route subclass specify the feature type followed by the subclass name, separated by a period. For example a route subclass called ‘test’ could be created for a type 3 shapefile containing M’s by specifying an Output feature class called ‘Route.test’.


Shapefiles were introduced in ArcView version 2 to allow limited editing of ArcView theme information. Each shapefile stores only one feature type: point, multipoint, line or polygon. Shapefile polygons may overlap.


Choose the data type mapping from INFO items to dBASE fields.

Default mapping - performs the default field-to-item data type definitions.

Define mapping - you explicitly define the name of each INFO item converted from the dBASE field.


The currently selected dBASE field contained within the Input shapefile. Select the field name you want to define in the new coverage.


The name of the INFO item that corresponds to the currently selected dBASE field.


Shapefile to Geodatabase Wizard

Converts a shapefile to a feature class in a geodatabase dataset.

Notes

A new feature class is created in the dataset you choose of a selected geodatabase. A dataset is your workspace in a geodatabase, where you may have a number of feature classes sharing a common projection and fitting within a specified domain (coordinate extent).

A Feature Class is a vector dataset that corresponds to a single type/collection of feature such as parcel , lake or transformer. A Feature Class consists of a number of features. A Feature Class can be a member of a Feature Dataset or it can be stand-alone. A stand-alone feature class contains features that have no topological associations with features in other feature classes. There is one type of geometry associated with the features in a feature class. The features in a simple feature class can have a geometry of type point, multipoint, polyline, or polygon.

Related Topics


Output feature class

You must browse for an SDE geodatabase connection if you want to add the shapefile to a new or an existing feature dataset. Use the Add SDE Connection tool, available through the browser or in ArcCatalog under Database Connections, to create a connection to a geodatabase if a connection does not exist.

If you want to create a feature dataset in a new OLE geodatabase, simply type in its name.

If you do not want to use the new feature class with other feature classes that share a similar extent and the same projection, you can create a stand alone feature class. If you have a number of shapefiles for the same area with the same coordinate system, we strongly recommend that you maintain all of them in one feature dataset for easier data management.

A domain is the coordinate extent of a dataset. No feature classes in the domain can have features that extend past these extents. If you are loading more than one shapefile into a new dataset, load the one with the largest coordinate extent first so that the domain of the dataset is large enough to contain all of the shapefile features you want.

All feature and attribute types in shapefiles are mapped to geodatabase geometry and attribute types. Shapefile feature types are very close to the different geometry types stored in a geodatabase, so their mapping is more straightforward. For detailed shapefile to geodatabase geometry type mapping click here

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.


Current spatial reference

When creating a stand alone feature class or creating a new feature dataset, the coordinate system and the domain extents will match that of the input data. Click Change… to alter the output coordinate system, and domain extent.

If the input and output coordinate systems are different, the features will automatically be projected. When adding a feature class to an existing feature dataset the coordinate system for the output feature class will automatically be set to match the coordinate system of the feature dataset.

Individual features with coordinates outside the X, Y and Z domain of the feature dataset will not be added to the output feature class. The M domain is excluded from this rule, feature with M values outside the M domain will still be added to the output feature class.

The coordinate range or domain extent of the output feature class is determined by the minimum coordinate, the maximum coordinate, and Precision values. Precision defines the scale of the dataset. The scale is the number of system units per one unit of measure. Therefore, this value specifies the degree of resolution. For example, in a projection system with meters as the unit of measurement, a precision value of 100 would be used to maintain centimeter-level resolution. Decreasing the Precision value increases the domain extent. Click Change… to alter the Precision value and the size of the domain extent.

Note: The default grid size value is in the units of the input projected coordinate system or geographic coordinate system. Changing the output coordinate system will require a new grid size, as it must be in the units of the output coordinate system. For example, if the input feature class has a geographic coordinate system and its units are decimal degrees, the default grid size may be 10. If the output coordinate system is set to be Lambert Conformal Conic with units in meters, the default grid size should be set to a value suitable for that new unit, such as 10000. If the default grid size is not updated, an error stating that the grid size is too small may occur or you may experience poor performance when working with the feature class as a result of an inappropriate grid size. If an error does occur, a new spatial index must be created for the feature class in ArcCatalog, before the feature class can be used.


Spatial index

The spatial index is used to quickly locate features in a dataset that might match the criteria of a spatial search.  Careful creation of a spatial index will increase the efficiency of your spatial searches.  A poorly defined spatial index will increase the time needed to complete a spatial search.

Different indexing schemes are available depending on what relational database holds the geodatabase.

 Personal geodatabase, Oracle binary, SQL Server, DB2

 Oracle Spatial

 Informix


Item to field mapping

Each different shapefile and dBASE field type maps to a single geodatabase type independent of field size. The exception is the Number type field, which will map to a long integer if its number of decimals is zero and to a double if its number of decimals is greater than zero. For more detailed information on shapefile and dBASE field type to geodatabase field type mapping click here

The Original Error field in the grid shows what problems have occurred when the wizard converted the dBASE items from the shapefile to the field type in the geodatabase dataset.

If the Original Error is ‘None’, then no problems were encountered. If a problem is encountered, the error is given and the new field is given a valid name, with the error being corrected automatically. For example, you may have two columns named REC_ID in a shapefile’s dBASE table, which is invalid in a SDE dataset, so the Original Error will be ‘Duplicate field name’. The Corrected Fields value will default to REC_ID1 for the second column having that name, but you are able to edit this field if you want to change the default correction. If you want to delete the field from the dataset, change the Delete Field setting by clicking on the grid value and selecting ‘Yes’ from the available drop down choices.


Shapefile to DXF

Converts shapefile spatial and attribute data to an AutoCAD ASCII Drawing Interchange (DXF) file.

Notes

The number of decimal digits to use when writing coordinates and other noninteger numbers in the DXF file.  This must be a number from 0-9.

Point shapefiles are written out as point entities.

Line shapefiles are written out as unclosed PolyLine entities in a block. Then an INSERT of the block is added to the entity section. Blocks are named BLKnnnnnn where nnnnnn is a number from 1-999999.

Polygon shapefiles are written out as closed PolyLine entities in a block. Then an INSERT of the block is added to the entity section. Blocks are named BLKnnnnnn where nnnnnn is a number from 1-999999.

During the conversion additional attribute information about lines and points is extracted from the shape dbf file if the following items are present.

LAYER - A character that specifies the layer name. The default layer will be SHP_POINT, SHP_LINE or SHP_POLY depending on the type of the shapefile.

COLOR - A numeric item containing the color of each dxf entity. The default color is white (7).

ELEVATION - The Z value of the entity. The default is 0.0.

THICKNESS - A numeric item whose value is the thickness of the entity. The default is 0.0.

Related Topics


The number of decimal digits to use when writing coordinates and other noninteger numbers in the DXF file.  This must be a number from 0-9.


Shapefile to Geodatabase

Converts a shapefile to a Geodatabase feature class and assigns it the ESRI Simple Feature behavior class.

When you import shapefiles, you create a new standalone feature class, a new feature dataset and feature class, or a feature class in an existing feature dataset. In the first two cases, you have to define a spatial reference.

If your shapefile has a defined projection, the tool will automatically create the new feature class with the same projection, unless you specify otherwise. If you do choose to import the data into a different projection than the source data is in, the features will automatically be projected.

Because all feature classes in a feature dataset share the same spatial reference, you must only specify a new spatial reference when loading the first feature class or when creating the feature dataset in ArcCatalog.

A suggested grid size is given based on the spatial reference, average feature size, and number of features in the input shapefile. The suggested grid size is only an approximation. You can determine the optimum grid size for any feature class by examining the data and the needs of the application querying it.

When you convert data from one format to another, a question arises about how data of a specific type maps from one format to the other. Importing data into the geodatabase is no exception. In this case, how both the spatial type and the attribute field type map from one data type to another must be considered. For each geodatabase field type, the field itself is persistently stored in the database differently depending on which RDBMS stores the geodatabase.

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings…. You may also choose to not include certain columns from the input table in the new Geodatabase table.

Notes

To create a new Geodatabase, type in the path and name of the Geodatabase to be created into Output Geodatabase. This functionality is not available from the mini-browser.

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the geodatabase you specify and whether you are using SDE or Access.

When loading data into an SDE geodatabase, you can specify a Configuration Keyword which references database storage parameters on the SDE server. For more information on creating SDE keywords, see the SDE Administration documentation.

All feature and attribute types in shapefiles are mapped to geodatabase geometry and attribute types. Shapefile feature types are very close to the different geometry types stored in a geodatabase, so their mapping is more straightforward. For detailed information on shapefile to geodatabase geometry type mapping click here

Each different shapefile and dBASE field type maps to a single geodatabase type independent of field size. The exception is the Number type field, which will map to a long integer if its number of decimals is zero and to a double if its number of decimals is greater than zero. For more detailed information on dBASE field type to geodatabase field type mapping click here

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Spatial Reference and Domain extents

Spatial index grid

Related Topics


The name of the shapefile you want to convert.


The name of the Geodatabase. It will contain the dataset and new feature class. To create a new Geodatabase, type in the name.


The name of a dataset that will contain the new feature class. If you choose an existing dataset, the new feature class will be added to it. If you specify a new dataset name, the feature class will be placed in the new dataset when it is created.


The name of the feature class to be created.

The feature class name cannot begin with a numeric character.


The settings that will be used during the conversion. Click the Change Settings… button to modify them.

Spatial reference: The output coordinate system determined from the input coverage feature class. The projection will be copied from the coverage, and the spatial domain calculated.

Grid size: The spatial index grid is a two-dimensional grid system that spans a layer, like the locator grid you might find on a common road map. It is used to quickly locate features in a dataset that might match the criteria of a spatial search.

Item names: Shows whether input item names have been modified or deleted. INFO  files allow characters in column names that other databases do not. The tool finds any illegal characters or reserved word field names in the input table, and corrects them for the output table.

Query: A SQL where clause that is used to create a selected set. Only the selected set will be converted to a feature class or table. If no expression is given, all features will be converted.

Keyword: A keyword that references database storage parameters on an SDE server. When loading data into an SDE Geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Geometry: M and Z values must be created at the same time as a feature class or feature dataset is created, as they can not be subsequently added. If the Enable M values on the output is checked the output feature class will have linear measurement (M) values. If you do not want your new feature class and/or feature dataset to contain M values, uncheck this option.


Shapefile to geodatabase geometry type mapping

Shapefile	Geodatabase geometry

point	point

point M	point with measures

point Z	point with Zs

polyline	line (polyline)

polyline M	line (polyline) with measures

polyline Z	line (polyline) with Zs

polygon	polygon

polygon M	polygon with measures

polygon Z	polygon with Zs

multipoint	multipoint

multipoint M	multipoint with measures

multipoint Z	multipoint with Zs


dBASE field to geodatabase field mapping

Field type	Field width	Gdb field type

Date	-	date

String	1–255	text

Boolean	-	text

Number	1–16 (decimals = 0)	long integer

Number	–16 (decimals > 0)	double


Simplify Buildings

Simplifies the footprint of buildings and creates a coverage with a preliminary region for each output building. The tool is used on large scale coverages—with buildings represented individually—to remove unnecessary or unwanted details from building footprints while maintaining their essential shape and size. Buildings are generally orthogonal areas, therefore simplification will preserve and enhance orthogonality.

Simplify Buildings recognizes buildings in three ways and their simplification differs accordingly:

Topologically disjoint – each separate building, with or without holes, is simplified by itself. To see an example, click [image].

Connected with straight lines that are near parallel to each other – simplified as a group. To see an example, click [image].

Connected in more complicated ways – not simplified. To see an example, click [image].

Based on the simplification Tolerance and the Minimum area, the boundaries of disjoint buildings or buildings connected with straight lines will be enhanced so that all near-90-degree angles become exactly 90 degrees. Based on given parameters, isolated, small intrusions will be either filled up or widened. Isolated small extrusions will be cut off. Some sides will be straightened or changed to simpler forms. The number of vertices will be reduced, but the measured area will remain roughly the same as the original. Any building or a group of connected buildings with a total area smaller than the Minimum area will be excluded. The maximum degree of simplification is reached when a building is reduced to a rectangle. To see an example of how tolerances affect simplification, click [image].

If the simplification tolerance is relatively large compared to the size of the building, the building is simplified directly to a rectangle centered at its own center of gravity. The area remains the same. The sides of the resulting rectangle have the same ratio as the sides of the bounding box aligned to the longest side of the original building. To see an example, click [image].

With the Check for building conflicts option on, the tool checks whether buildings are overlapping or touching, and can avoid some spatial conflicts. Using this option can considerably increase processing time.

All attributes in the Input coverage polygon attribute table (PAT) are copied to the Output coverage region subclass BLDGSIM. Two items are added to the <Output coverage>.PATBLDGSIM:

BDS-STATUS records a simplification status for each building.

BDS-GROUP records a unique positive value for each group of connected buildings. A single building has a BDS-GROUP value of zero. A single building with a hole receives a unique negative value for both the outer and inner boundaries.

Recommended post-processing

The tool sets the region subclass AREA values to zero and computes their PERIMETER. To get fully built regions and the AREA values, use the Clean tool with the Poly option.

Use the Find Building Conflicts tool to identify buildings that overlap or are too close together. This process requires that you first use the Clean tool.

Notes

Create a spatial index on the Input coverage with ArcCatalog to make the tool run faster.

If a Selection file is not specified, or if it contains no polygons, all polygons are selected for simplification.

Tool execution stops if the Selection file does not contain the polygon feature class, or if it does not match the Input coverage (that is, the Selection file was not derived from the Input coverage.)

Tool execution also stops if more than 500 adjacent polygons in a group are detected.

The <Output coverage>.AAT stores only new arcs; it does not maintain information from the Input coverage arcs.

All route and region attributes and topology from the Input coverage are lost.

Simplify Buildings works only on the entire building boundary.

Related Topics


Choose the coverage with buildings you want to simplify.


The Tolerance setting determines the extent to which buildings will be simplified. Its value, in coverage units, must be greater than zero (0).


Minimum area is the smallest size for buildings to be included in the Output coverage. A building or group of connected buildings with a footprint smaller than the Minimum area is not included in the Output coverage.

The default value displayed here is the square of the Tolerance value you entered above. Change this value to suit your needs. Use the value 0 to simplify all building footprints.


The coverage you will create.


The BDS-STATUS values are:

1	A completely simplified separate building.

2	A separate building, partially simplified due to a spatial conflict. If a spatial conflict is found, the building will not be simplified further.

3	The resulting separate building contains a side smaller than the simplification tolerance.

4	Fully or partially simplified buildings connected with straight lines. For buildings connected with straight lines, simplification is limited to simple rules only. Therefore, the simplified results are not consistent with disjoint buildings.

5	Buildings connected in a complicated way are not simplified.


A Selection file identifies previously selected features of the Input coverage. This file is created in ARCPLOT and must already exist. This option allows you to simplify a selected subset of buildings from the Input coverage.

If a Selection file is not specified, all polygons are selected for simplification.


Choose whether to check for building conflicts.

Unchecked – Does not look for potential spatial conflicts, such as overlapping or touching, among buildings. This option considerably speeds up processing time.

Checked – Determines potential spatial conflicts between buildings and flags them to avoid overlapping output buildings. This option results in longer processing time.


Example for large simplification Tolerance


Each separate building is simplified by itself


Buildings connected with straight lines are simplified as a group


Buildings connected in a complicated way are not simplified


Partially simplified buildings due to spatial conflict


How tolerances affect simplification.


SLF to Coverage

Converts a Standard Linear Format (SLF) file to a coverage.

Notes

Although the SLF format does describe and include other data structures, the SLF-2D ITD format is the only SLF format that the ArcInfo SLF translator supports.

Topology is built for the coverage automatically. Due to the possibility of creating disjoint features, only Build is run. If the Build bails out then Clean should be run. If Clean creates disjoint features, then a smaller tolerance should be used or the SLF data will need to be fixed by the supplier.

Coverages coordinates are always Geographic based on the WGS 84 ellipsoid. Projection information is written to the projection file. The coordinates will always be positive.

Attribute information is stored in INFO tables associated with the feature attribute tables. The codes used are described by NIMA's DMAFF feature coding scheme for feature attribute coding.

Complex feature relationships are stored in the join tables.

Use the Relate Manager to restore the relate environment that will connect features to attributes in the code tables through the corresponding join tables.

Example output

Supported file extension

Related Topics


The SLF file you want to convert to a coverage.

NOTE: The tool supports only the SLF-2D ITD format.


The coverage you will create. It will contain lines and/or polygons. Any points are written to a separate coverage, named <cover>_p.


Example output

Results of the SLF to Coverage tool:

Thematic File Type:      SURFACE DRAINAGE
Security Classification: UNCLASSIFIED
Security Handling:       DISTRIBUTION LIMITED
Total Segments: 1665
Total Features: 845
Point Features:  72
Linear Features: 703
Area Features:   70
Cleaning \MISC\PC\TEST\SLF\DATA\S
Building polygons...
Re-building AAT...

The relates created by the tool:

Relate Name:        AJOIN
Table:              \misc\pc\test\slf\data\s.ajoin
Database:           INFO
Item:               slfcov-ID
Column:             slfcov-ID
Relate Type:        ORDERED
Relate Access:      RW
Relate Name:        PCODE
Table:              \misc\pc\test\slf\data\s.pcode
Database:           INFO
Item:               slfcov-ID
Column:             FEAT-ID
Relate Type:        ORDERED
Relate Access:      RW
Relate Name:        ACODE
Table:              \misc\pc\test\slf\data\s.acode
Database:           INFO
Item:               FEAT-ID
Column:             FEAT-ID
Relate Type:        ORDERED
Relate Access:      RW

The INFO tables created by the tool:

DF  SLFCOV_P.PAT        ARC0070DAT           72      16    XX
DF  SLFCOV_P.XCODE      ARC0071DAT           72      7
DF  SLFCOV_P.XJOIN      ARC0072DAT           72      10
DF  SLFCOV.ACODE        ARC0073DAT          703      70
DF  SLFCOV.AJOIN        ARC0074DAT         1284      10
DF  SLFCOV.PCODE        ARC0075DAT           70      70
DF  SLFCOV.RELATE       ARC0076DAT            3     220
DF  SLFCOV_P.RELATE     ARC0077DAT            2     220


Spatial Adjustment

Adjusts a feature class or shapefile based on source and destination coordinates in a link file.

The Spatial Adjustment tool supports transformation and rubbersheet adjustments.  The supported transformation methods include:  Affine, Projective, and Similiarity.  The supported rubbersheet methods include:  Natural Neighbor and Linear.

Link files are text files that contain source and destination coordinates that define the spatial adjustment.  These files are tab delimited text files and contain a link id column (optional), a pair of source coordinates, and a pair of destination coordinates.  You can view the link coordinates using the Link Table.  This tool will also display the residual error (only for transformations) and allow you to remove links from the adjustment.

You can specify the same input and output feature class or shapefile for the adjustment or you can create a new output feature class or shapefile by specifying a new name.  Link files can be used more than once in the same operation when adjusting multiple feature classes or shapefiles in the batch environment.

The output Coordinate System is determined from the Input feature class. This can be modified if you are loading the feature class into a new feature dataset or a stand-alone feature class. If you are loading into an existing feature dataset, these parameters cannot be altered.

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings. You may also choose to not include certain columns from the input table in the new Geodatabase table.

This process does not preserve object identity and always results in a simple feature class that contains no subtypes, default values, and so on.

Notes

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the Geodatabase you specify and whether you are using SDE or Access.

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Spatial Reference and Domain extents

Related Topics


The feature class or shapefile you want to adjust.


The link file that defines the source and destination coordinates for the adjustment.


Opens the link table.


Changes layer coordinates using an affine, similarity or projective transformation based on a set of control points (links).

Converts data from one coordinate system to another. It is often used to convert layers created in digitizer units (most often inches) into the real-world units represented on the map manuscript. These real-world locations are represented by a particular projection; for example, the projection of your base map may be UTM with control point locations measured in meters.

To perform a transformation, you must be able to register at least two control points in your layer to real locations. These real locations may be measured in feet or meters using the base map coordinate system, or they may be located at latitude-longitude intersections.

Affine - At least three control points are required to define this transformation method. Affine is the default transformation method. The affine equations use six parameters.

Projective - This method requires a minimum of four control points to define the transformation. The projective transformation is only used to transform coordinates digitized directly off high altitude aerial photography or aerial photographs of relatively flat terrain assuming that there is no systematic distortion in the air photos. Projective uses eight parameters.

Similarity - At least two control points are necessary for this transformation method. This transformation is known also as a Helmert, orthogonal, or two-dimensional linear conformal, or four-parameter transformation.


Corrects map flaws and distortions through the geometric adjustment of coordinates.

During rubber sheeting, the map is literally stretched, moving features using a piecewise transformation that preserves straight lines.

Natural Neighbor – This method of interpolation uses a weighted average of surrounding or neighboring data points to compute the interpolation. The generated surface is smooth and continuous while honoring all the data, and the tautness of the surface is controlled by the user.  Natural Neighbor is the default rubbersheet method.

Linear - This method of interpolation considers the rubbersheeting surface as a continuous faceted surface formed by triangles.  The normal, or perpendicular to the slope of the surface, is constant throughout the extent of each triangle facet.


The name of the output Geodatabase or shapefile.  To create a new Geodatabase or shapefile, type in the new name.


The name of a new or existing dataset that will contain a new or existing feature class in the specified Geodatabase; it is optional.


The name of a new or existing feature class. The feature class name cannot begin with a numeric character.


Provides access to the Output Settings dialog, where you can view and change the spatial reference, change the Grid Size, and edit the items of the output feature class.


Split

Clips portions of the Input coverage into multiple coverages. Each new Output coverage contains only those portions of the Input coverage features overlapped by the Split coverage polygons with a matching Split item value.

Split discovers the feature classes in the Input coverage and offers the available clipping methods:

Poly – polygons and region subclasses are split and a PAT saved. The label point for each remaining polygon is moved only if its original location falls outside the clipping boundary. Region subclasses are maintained. Route-systems are ignored.

Line – arcs are split and an AAT saved. Route-systems are maintained.

Point – points are copied and a PAT saved.

Poly & Line (Net) – polygons and arcs are clipped, and their PAT and AAT are saved. Route-systems are maintained.

Line & Point (Link) – arcs and points are split, and their AAT and PAT are saved. Route-systems are maintained.

Geometry – points, arcs, and annotation in a coverage without topology (no attribute files) are split. Attributes are ignored.

Notes

Annotation is copied when its lower-left starting point falls within a new Output coverage.

Attributes for new nodes are set to zero.

Route-systems are copied when their arcs are split into multiple pieces, and dropped for arcs that are removed.

Region subclasses are maintained as empty subclasses when all the regions are removed.

How the default fuzzy tolerance is calculated

Processing planar graphs

Related Topics


The coverage you want to split.


The coverage containing polygons that you will select based on their Split item value to define which Input coverage features are copied to the Output coverages.


Choose a numeric item whose value will identify the Split coverage polygons used for clipping.


Choose the feature class you want to split.

Poly – polygons and region subclasses

Line – arcs

Point – points

Poly & Line (Net) – polygons and arcs

Line & Point (Link) – arcs and points

Geometry – points, arcs, and annotation in a coverage without topology are clipped. Attributes are ignored.


The minimum distance within which coordinates, arcs, and intersections in the Output coverage are merged. The default is taken from the Input coverage or Split coverage, whichever is smaller. Its unit of measure is that of either one of the input coverages.


Specify a coverage name, then choose its Split item value.


Specify a value for selecting Split coverage polygons which define the clipping area for this Output coverage. Then add this combination to the List of output coverages.


Lists the specified Coverages and their Split item values.


Adds the specified Coverage and Split item value combination to the List of output coverages.


Removes the selected Coverage and Split item value combination from the List of output coverages.


Statistics Wizard

The Statistics Wizard  helps you to analyze the attribute values in an INFO table. It combines the functionality of the Frequency and Summary Statistics tools.

You can determine the frequency of unique values for certain attributes, or calculate statistics for attributes.

Related Topics


Choose the type of statistics you want to perform

Frequency

Determine the frequency of unique values for selected attributes creates a table of unique occurrences of the attribute items that you specify and a count of how many times those combinations occur. You may choose to summarize a particular item on each unique combination of frequency items. The output INFO table has items named FREQUENCY, and CASE#, along with each specified attribute and summary item. If you specify a reference item, that item takes the place of CASE#, and is also written to the input table.

Summary statistics

Calculate the Sum, Maximum, Minimum, Mean or Standard Deviation values for attributes creates a table of summary statistics for the items and expressions that you specify. You may choose to use a weight value or weight item in your statistical expression. The resulting INFO table has an item named FREQUENCY and an item for each statistical expression. If you choose to calculate statistics for each value of a specific item, that item will also be in the output table, along with a record for each value. If you instead calculate statistics for all records, there will be only one record in the output table.


Choose the items to analyze

The items you choose are used together to form unique combinations of values. Each unique combination will be used in the frequency analysis.

For example, if you choose only item CODE from the following table:

Record          AREA    PERIMETER    C#  C-ID CODE COST
     1        -4.000        8.000     1     0 111    0
     2         1.000        4.000     2     3 111   30
     3         1.000        4.000     3     4 111   40
     4         1.000        4.000     4     1 999   10
     5         1.000        4.000     5     2 999   20

your Output table would have two records, one for each occurrence of the unique CODE values:

Record  CASE# FREQUENCY CODE
     1      1     3     111
     2      2     2     999

If you choose items CODE and PERIMETER, then your Output table would have three records, one for each unique occurrence of CODE and PERIMETER values:

Record   CASE# FREQUENCY CODE    PERIMETER               COST
     1       1     2     111         4.000          70.000000
     2       2     1     111         8.000           0.000000
     3       3     2     999         4.000          30.000000


Summary items

Items that you choose for summary analysis will be in the Output table. The values will be the summary of all the values of the records with each unique combination of the Frequency items.

For example, from the following table, you choose CODE as the Frequency item, and COST as a Summary item.

Record          AREA    PERIMETER    C#  C-ID CODE COST
     1        -4.000        8.000     1     0 111    0
     2         1.000        4.000     2     3 111   30
     3         1.000        4.000     3     4 111   40
     4         1.000        4.000     4     1 999   10
     5         1.000        4.000     5     2 999   20

The Output table will look like this:

Record  CASE# FREQUENCY CODE               COST
     1      1     3     111           70.000000
     2      2     2     999           30.000000


Case item

The Output table always has a Case item, which keeps track of the number of unique combinations (cases) of the Frequency items. If you do not check Add case item to input table, the Input table is unchanged, and an item named CASE# is added to the Output table that stores the Output table record number.

An example Output table:

Record  CASE# FREQUENCY CODE
     1      1     3     111
     2      2     2     999

If you want to relate the Output table and Input table by the Case item, you can check Add case item to input table and specify the name of a Case item. That item is then added to both the Output table and the Input table. Like CASE#, the Output table item value is the Output table record number. The Input table item value is the record number of the Output table to which that input record was classified.

For example, after specifying a Case item NEW, the Output table looks like this:

Record    NEW FREQUENCY CODE               COST
     1      1     3     111           70.000000
     2      2     2     999           30.000000

and the Input table looks like this:

Record          AREA    PERIMETER    C#  C-ID CODE COST   NEW
     1        -4.000        8.000     1     0 111    0      1
     2         1.000        4.000     2     3 111   30      1
     3         1.000        4.000     3     4 111   40      1
     4         1.000        4.000     4     1 999   10      2
     5         1.000        4.000     5     2 999   20      2


Build statistical expressions

Build one or more statistical expressions using a Statistical method and an Item, and optionally, a Weight item or Weight value.

Use the ‘Add to list’ button to enter the expression into the expression list box. Highlighted expressions may be deleted. To edit the expressions in the list box, highlight the expression you want to edit, make the changes you need using Statistical method, Item, and weights, then click on ‘Edit in list’. This replaces the highlighted expression with the current expression.

Statistical methods

Sum - adds the total value for Item. If Weight item or Weight value is specified, the value of Item is multiplied by Weight item or Weight value for each record and then summed for all records.

Maximum- finds the largest value for all records of Item or of the product of Item, Weight item, or Weight value if Weight item or Weight value are specified.

Minimum - finds the minimum value for all records of Item or of the product of Item, Weight item or Weight value if Weight item or Weight value are specified.

Mean - calculates the average for Item or the weighted average if Weight item or Weight value is specified. The weighted average is determined by calculating the total sum of the products of Item, Weight item, or Weight value for each record and dividing this total by the sum of the Weight item or Weight value values for all records.

Standard Deviation - finds the standard deviation on values for Item. Weight items and values are not used.


Calculate values

If you choose ‘Calculate statistics for all records’, there will be one record in the Output table, with statistics summarized for all items.

If you choose to calculate statistics for an item, the Output table will contain a record for each item value, and statistics will be calculated separately for the item values.

For example, you choose the item STREET-NAME on which to calculate statistics, and you build the expressions 'Sum LENGTH' and 'Mean LENGTH'. The output table will look like this:

1
STREET-NAME      =  ALABAMA
FREQUENCY        =     15
SUM-LENGTH       =       9,206.701
MEAN-LENGTH      =         613.780

2
STREET-NAME      =  PENNSYLVANIA
FREQUENCY        =      8
SUM-LENGTH       =       5,190.298
MEAN-LENGTH      =         648.787

3
STREET-NAME      =  CHURCH
FREQUENCY        =     17
SUM-LENGTH       =       7,870.459
MEAN-LENGTH      =         462.986


Summary Statistics

Generates summary statistics for items in an INFO Input table and saves them in an INFO Output table. The Weight value option allows the use of a real or integer constant for weighting the statistical expressions.

Case item is the name of an item in the Input table for which summary statistics are calculated separately for each value. One record is created in the Output table for each Case item value. If no Case item is specified, one set of statistics is calculated using all records in the Input table, and one record is written to the Output table. There can be an unlimited number of unique Case item values.

The Weight Value is used to increase or decrease the output statistical values by a given factor.  If the  Constant option is used, the statistical expression will be performed on the Item’s values multiplied by the constant weight value. If the From item option is used, the statistical expression will be performed on the Item’s values multiplied by the value in the From item of each record.

  Statistical expressions

  Naming conventions for items in the Output table

Notes

All items for which summary statistics are generated must be defined as numeric (i.e., I, B, F or N item types).

If a Weight value Constant or From item is negative, it will be used as a negative number to calculate the product of the Weight value and Item. However, the absolute value will be used to sum the weights for a weighted mean. If the From item value or Constant is 0, the record will be skipped.

Due to the way items are named in the Output table, you should only specify one weighted mean for a single item to avoid duplicate item names. For example, if you wanted to find two weighted averages for the same Item using two different From items, both of the resulting items in the Output table would be named MEAN-W-<Item>. This limitation for naming Output table items also holds for weighted sums, weighted minimums and weighted maximums.

Example

Related Topics


Statistical expressions

The tool helps you build statistical expressions with Statistics, Item, and optional Weight value {Constant | From item}. Up to 25 statistical operations can be entered. Below are descriptions of each format and how to use it.

Sum <Item> {Constant | From item} – Adds the total value for <Item>. If a {Constant | From item} is specified, the value of <Item> is multiplied by {Constant | From item} for each record and then summed for all records.

Mean <Item> {Constant | From item} – Calculates the average for <Item> or the weighted average if {Constant | From item} is specified. The weighted average is determined by calculating the total sum of the products of <Item> times {Constant | From item} for each record and dividing this total by the sum of the {Constant | From item} values for all records.

Minimum <Item> {Constant | From item} – Finds the minimum value for all records of <Item> or of the product of <Item> times {Constant | From item} if {Constant | From item} is specified.

Maximum <Item> {Constant | From item} – Finds the largest value for all records of <item> or of the product of <Item> times {Constant | From item} if {Constant | From item} is specified.

Standard Deviation <Item> – Finds the standard deviation on values for <Item>.


Naming conventions for items in the Output table

ITEM NAME        DESCRIPTION

{Case item}     Only included when Case item is given
FREQUENCY       Count of occurrences
SUM-<Item>      Result of SUM <Item>
SUM-W-<Item>    Result of SUM <Item> {weight_item}
SUM-CW-<Item>   Result of SUM <Item> {weight_value}
MEAN-<Item>     Result of MEAN <Item>
MEAN-W-<Item>   Result of MEAN <Item> {weight_item}
MEAN-CW-<Item>  Result of MEAN <Item> {weight_value}
MAX-<Item>      Result of MAXIMUM <Item>
MAX-W-<Item>    Result of MAX <Item>  {weight_item}
MAX-CW-<Item>   Result of MAX <Item>  {weight_value}
MIN-<Item>      Result of MINIMUM <Item>
MIN-W-<Item>    Result of MIN <Item>  {weight_item}
MIN-CW-<Item>   Result of MIN <Item>  {weight_value}
STD-<Item>      Result of STD <Item>

Note that item names that have more than 16 characters will be truncated in INFO. The 16 characters include the prefix (e.g., SUM, MAX or MEAN) that is attached to the beginning of the Item name. For example, the product of the statistical expression SUM LENGTH will be named SUM-LENGTH.


Example

This example shows the use of Summary Statistics to summarize street length for each street in a coverage named STREET. The item STREET-NAME is used as the Case item so that statistics are summarized separately for each street. The following shows the completed tool and the resulting Output table.

Item definitions of ST-STATS:

COLUMN  ITEM NAME         WIDTH OUTPUT TYPE N.DEC

     1  STREET-NAME          15     15    C     -
    16  FREQUENCY             4      5    B     -
    20  SUM-LENGTH            8     18    F     6
    28  MEAN-LENGTH           8     18    F     6
    36  MAX-LENGTH            8     18    F     6
    44  MIN-LENGTH            8     18    F     6
    52  STD-LENGTH            8     18    F     6

Item values of ST-STATS:

1
STREET-NAME      =  ALABAMA
FREQUENCY        =     15
SUM-LENGTH       =       9,206.701
MEAN-LENGTH      =         613.780
MAX-LENGTH       =       1,393.229
MIN-LENGTH       =          52.955
STD-LENGTH       =         547.618

2
STREET-NAME      =    PENNSYLVANIA
FREQUENCY        =      8
SUM-LENGTH       =       5,190.298
MEAN-LENGTH      =         648.787
MAX-LENGTH       =       1,437.040
MIN-LENGTH       =         296.100
STD-LENGTH       =         494.832

3
STREET-NAME         CHURCH
FREQUENCY        =    17
SUM-LENGTH       =       7,870.459
MEAN-LENGTH      =         462.986
MAX-LENGTH       =       1,322.369
MIN-LENGTH       =         152.986
STD-LENGTH       =         351.742


The table you want to analyze with Summary statistics.


The table of summary statistics you will create.


Lists all the items in the Input table. If you choose a Case item, summary statistics are calculated separately for each value and stored as separate records in the Output table.

If you do not choose a Case item, one set of statistics will be calculated for all records in the Input table and stored in one record in the Output table.


Lists the available statistical methods:

Sum – adds the total value for the Item you selected. If you specify a Weight value, then the Item value is multiplied by the Weight value for each record and then summed for all records.

Mean – calculates the average for the Item you selected. If you specify a Weight value, then the weighted average is determined and divided by the sum of the Weight values for all records.

Minimum – determines the smallest value for all records of the Item you selected or, if you specify a Weight value, the smallest product of the Weight value and the Item.

Maximum – determines the largest value for all records of the Item you selected or, if you specify a Weight value, the largest product of the Weight value and the Item.

Standard Deviation – determines the standard deviation of values for the Item you selected.


Lists the numeric items in the Input table. Choose the Item for which you want to calculate statistics.


Choose the type of Weight value you want to use while calculating statistics.

None – no weight is applied.

Constant – the value is multiplied by the value of Item.

From item – allows you to choose a numeric item from the Input table. That item value is multiplied by the value of Item.

See Statistical expressions for a description of Weight values with each statistical method.


Lists the numeric items in the Input table. Choose the one whose value you want to multiply by the Item value when calculating statistics.


Enter the number you want to multiply by the Item value when calculating statistics.


The statistical expression you are building.


Adds the current statistical expression to the list for execution.


Deletes the selected statistical expression from the list.


Replaces the selected expression from the list with the current statistical expression.


Lists the statistical expressions you want to perform on the Input table.


Table to Point Coverage

Converts an INFO or a dBASE table or a text file with X and Y coordinates to a point coverage.

The tool works only with stand-alone INFO and dBASE tables. Coverage feature class tables (FATs) and shapefile dBASE tables cannot be converted.  Table to Point Coverage uses the ArcInfo commands Generate, Build and Joinitem to generate the Output coverage.

Attribute information present in the Input X-Y table is transferred to the output coverage.  The Text file conversion options are used to define the field properties for the Output coverage’s PAT.

Notes

The tool requires geographic coordinates to be in decimal degrees, not Degrees Minutes Seconds.

Z-values can be transferred as an attribute, not as a coordinate.

The tool builds the Output coverage with point topology.

Sample text file

Related Topics


Choose the data source type of the Input X-Y table

Info table - an INFO table

dBASE table - a dBASE (dbf) file

Text file - a comma delineated ASCII file


The name of the table containing the X and Y coordinates.


The field in the Input X-Y table containing the X coordinate.


TThe field in the Input X-Y table containing the Y coordinate.


Displays the contents of the text file in a side window.


Generate adds features to a coverage.


JoinItem merges two INFO data files based on a shared item.


Sample text (comma-delimited ASCII) file with X and Y coordinates

'Site A',-152575.109,6598786.500
'Site B',-672937.688,6704094.000
'Site C',-730404.311,6090703.500
'Site D',-788363.750,6909014.000


Tiger to Coverage
Tiger to Coverage Wizard

Converts a set of U.S. Bureau of Census TIGER/Line files into one or more ArcInfo coverages.

Notes

The wizard converts all versions released after April 1989. The minimum input required are Record Types 1 & 2.

The wizard does not support Record Types F and G released with the 1992 School District version. These are temporary record types, not found in earlier or subsequent versions.

The data dictionary for the Tiger/Line version you are converting may be found at the US Census bureau’s TIGER web site (www.census.gov/geo/www/tiger). Review the technical description of the TIGER dataset version you are using for attribute definitions.

 	Naming convention of TIGER/Line (r) files released by the Census Bureau

List of the release year code suffixes and what they mean

Related Topics


TIGER Attributes

The following links describe which TIGER files are converted for each feature. Refer to the U.S. Census Bureau’s TIGER ’98 specification paper for a complete description of the items found in each file.

Converting line features

Converting area point features

Converting landmarks


Converting line features

The Output line coverage or Output polygon and line coverage will contain basic TIGER/Line feature and line attribute data from files type 1 through 6, H, and Z. If you are using a complete set of TIGER/Line files, the new coverages will contain line features and the following attribute tables:

ACODE - the attribute information in this table reflects the most current geography available at the time the TIGER dataset was released. Attributes include a permanent record number (TLID), street address, and legal and statistical area boundaries for each line segment. This table is related to the arc attribute table (AAT) via <cover>-ID.

TYPE3 - contains geographic area codes from the last census taking, that is, the TIGER/Line datasets will have the 1990 census information in this table. TYPE3 is related to the AAT via TLID.

TYPE5 - contains alternate street names and address information for line features and is related to the AAT via TLID.

TYPE6 - contains additional address range and zip code information for line features and is related to the AAT via TLID. Datasets containing ZIP+4 codes, records in the TYPE6 file are also related to TYPEZ via redefined item TLIDSQ.

TYPEH - contains the source and history codes for TLIDs and is related to the AAT via TLID.

TYPEZ - contains ZIP+4 Postal Add-on Codes. They relate to records to TYPE6 records by a combination of TLID and RTSQ via redefined item TLIDSQ.


Converting area point features

The Output area point coverage or Output polygon and line coverage contain polygon locations and area attributes from files type 9, A, C, I, P, R, and S. If you are using a complete set of TIGER/Line files, the point coverage will contain point features and the following attribute tables:

XCODE - contains the unique polygon identifiers. This table is related to the point or polygon attribute table (PAT) via <cover>-ID.

TYPE9 - contains Key Geographic Locations (KGLs) and is related to the PAT via redefined item CENPOLID.

TYPEA - contains the basic census geographic area codes (State, County, MCD, Census Tract, and Tabulation Blocks). This table is related to the PAT via <cover>-ID.

TYPEC - contains a non-hierarchial flat file containing a unique list of geographic codes. This table does not relate to any feature attribute table.

TYPEI - contains TLIDs, and the left and right polygon identifiers for each line segment. TYPEI is related to the AAT via TLID. The TYPEI table can usually be deleted because these topological relationships are generated and maintained within ArcInfo.

TYPER - contains the record number range. This table does not relate to any feature attribute table.

TYPES - provides additional space to identify polygons and is generally used by participants in programs to return proposed geographic area codes to the Census Bureau. TYPES is related to the PAT via redefined item CENPOILD.


Converting landmarks

TIGER/Line files type 7 and 8 contain landmark points and landmark area attributes. The Output landmark point coverage converts type 7 to landmark point features and attributes, and file type 8 to area attributes with a polygon identifier that can be linked to point features representing polygons in the Output area point coverage.

If your TIGER dataset contains both point and area landmarks, the Output point coverage will have point features and the following attribute tables:

XCODE - contains Landmark attributes for points only. Landmark area attributes appear in TYPE8. This table is related to the Output landmark point coverage PAT via cover-ID.

TYPE8 - contains Landmark area attributes. The Key Geographic Locations (KGLs) will appear in table named TYPE9. The TYPE8 table is related to the Output point coverage PAT via redefined item CENPOILD.


Results of simple option

The output coverage(s) will not be processed. The associated attribute tables will remain separate, requiring you to access them using a relate item. This method may be used if you do not want to use the associated attribute tables and do not require planar coordinates. The projection and any relates will not be defined for the output coverage(s).


Release year code suffixes

.f2* for the Pre Census TIGER/Line files
.f4* for the 1990 Census TIGER/Line files
.f5* for the 1992 TIGER/Line files
.f6* for the 1994 TIGER/Line files
.bw* for the 1995 TIGER/Line files with NAD27
.bwn for the 1995 TIGER/Line files with NAD83 (released 1997)


TIGER/Line files are a digital database of geographic features, such as roads, railroads, rivers, lakes, political boundaries, census statistical boundaries, etc. covering the entire United States. The database contains information about these features such as their location in latitude and longitude, the name, the type of feature, address ranges for most streets, the geographic relationship to other features, and other related information. They are the public product created from the Census Bureau's Topologically Integrated Geographic Encoding and Referencing (TIGER) database of geographic information. TIGER was developed at the Census Bureau to support the mapping and related geographic activities required by the decennial census and sample survey programs. (Referenced from US Census Bureau’s web site.)


Tiger Naming convention

tgr	=	TIGER
28	=	state code (Mississippi)
019	=	county code (Carver County)
.	=	period
bw	= 	release year code
*	=	wildcard for 1 or 2 more characters


Conversion options

It is recommended that you create a polygon coverage containing line and area attributes and a point coverage with landmark attributes as it will produce ready to use coverages.

Results of the recommended processing option

Results of the simple conversion option


Tin to Coverage

Converts a tin to a double-precision coverage.

Notes

For the Poly option, the tool creates a polygon coverage, where each tin triangle becomes a polygon. It adds attribute values for DEGREE-SLOPE or PERCENT-SLOPE, ASPECT, and SAREA to the polygon attribute table (PAT). For details click [image].

For the Line option, the tool creates a line coverage where each tin edge becomes a line. It adds attribute values for DEGREE-SLOPE or PERCENT-SLOPE, LSLOPE, RSLOPE, LASPECT, RASPECT, ZFROM, ZTO, and SFTYPE to the arc attribute table (AAT). For details click [image].

For the Point option, the tool creates a point coverage, where each tin node becomes a point. It adds the item SPOT, containing surface z values, to the point attribute table (PAT). For details click [image].

For the Hull option, the tool creates a polygon coverage with one or more polygons outlining the tin’s interpolation area. You can use these polygons as a clip coverage to ensure that all features are within the tin’s interpolation area. For details click [image].

Related Topics


Poly option

These items are always added to the Output coverage polygon attribute table (PAT):

ITEM NAME      WIDTH  OUTPUT  TYPE  N.DEC
DEGREE_SLOPE or
PERCENT_SLOPE     4     12     F      3
ASPECT            4     12     F      3
SAREA             8     18     F      5

DEGREE_SLOPE or PERCENT_SLOPE - the maximum rate of change in z values across the triangle facet polygon. For example, a rise of 2 meters over a distance of 100 meters is calculated as a DEGREE_SLOPE angle of 1.15û, or as a PERCENT_SLOPE of 2 percent.

ASPECT - the compass direction of the maximum rate of descent across the triangle facet facing downhill. ASPECT is expressed in positive degrees from 0 to 360, measured clockwise from the north. For example, Aaslope facing due east has an ASPECT of 90; a slope facing due west has a value of 270. Triangles having a PERCENT_SLOPE of less than 1 percent or a DEGREE_SLOPE less than 34’ are considered to be flat. These flat triangles have no aspect and receive an ASPECT value of -1.

SAREA - the surface area of each triangle facet in ground UNITS. Except for flat triangles, the SAREA (measured along the slope) is greater than the planimetric AREA (measured in the horizontal plane). A Z-factor is essential for correct slope calculations when the Input tin surface z-units are expressed in a different unit of measure than the ground units.

This item is added to the PAT when the Hillshade option is used:

ITEM NAME      WIDTH  OUTPUT  TYPE
SHADE_INDEX       4     5       B

SHADE_INDEX - a reflectance value representing shaded relief for each triangle facet. These values are calculated by projecting an artificial light source onto the plane defined by each triangle. Output values range from 1 to 255, with 1 representing the darkest areas and 255 the brightest.

A Z factor can be used to adjust contrast in the reflectance values placed in SHADE_INDEX. Increasing the Z factor will increase the contrast. Be aware that this will result in incorrect output DEGREES_SLOPE or PERCENT_SLOPE values.


Line option

These items are always added to the Output coverage arc attribute table (AAT):

ITEM NAME      WIDTH  OUTPUT  TYPE  N.DEC
DEGREE_SLOPE or
PERCENT_SLOPE     4     12     F      3
LSLOPE            4     12     F      3
RSLOPE            4     12     F      3
LASPECT           4     12     F      3
RASPECT           4     12     F      3
ZFROM             4     12     F      3
ZTO               4     12     F      3
SFTYPE            4      5     B      -

DEGREE_SLOPE or PERCENT_SLOPE - rate of change in z value over the length of the arc expressed in degrees or as a percentage.

LSLOPE - slope of the left adjacent triangle facet (LPOLY) expressed in degrees or percent. Arc direction is in relation to the FNODE and TNODE orientation. An LSLOPE or RSLOPE value of -9999 indicates that the arc is on the boundary of the region of interpolation defined by the hull or an exclusion area within the tin.

RSLOPE - slope of the right adjacent triangle facet (RPOLY) expressed in degrees or percent.

Users are sometimes confused between slope measurements expressed in degrees and percent. Consider triangle B where the angle of the slope is 45 degrees. The rise is equal to the run. Expressed as a percentage, the angle is 100%. Note that as the slope angle reaches vertical (90 degrees), the percentage slope approaches infinity.

LASPECT - aspect of the left adjacent triangle. See the discussion of ASPECT in the Poly option.

RASPECT - aspect of the right adjacent triangle. See the discussion of ASPECT in the Poly option.

ZFROM - surface z value of the FNODE.

ZTO - surface z value of the TNODE.

SFTYPE - integer value of the surface feature type of the Output coverage arc. Arcs representing HARD Input tin breaklines are assigned an SFTYPE value of 3. Arcs representing SOFT Input tin breaklines are assigned an SFTYPE value of 2. All other Input tin non-breakline edges are assigned an SFTYPE value of 0.

The Output coverage arcs are oriented in a downward direction; that is, the FNODE is the node with the higher z value. The orientation of the arc is arbitrary when both nodes have the same z value.

The use of a Z factor is essential for correct slope calculations when the Input tin surface ZUNITS are expressed in a different unit of measure than the ground units.

Negative slopes indicate that the slope is downward relative to the arc; positive slopes are upward.

In regions of uniform slope or aspect, adjacent triangles have the same aspect and absolute slope. In these cases, the LASPECT and RASPECT will be the same, and LSLOPE and RSLOPE will have the same absolute values.

Arcs on the hull lack surrounding data to calculate values for LSLOPE, RSLOPE, LASPECT and RASPECT. The missing values are assigned the NODATA value, -9999.


Point option

This item is always added to the Output coverage pointattribute table (PAT):

ITEM NAME      WIDTH  OUTPUT  TYPE  N.DEC
SPOT              4     12     F      3

SPOT - surface z value for the point.


Hull option

The HULL option creates a polygon coverage defining the Input tin zone of interpolation.

If the tin was created with the Arc command ARCTIN, the hull is defined by one convex polygon. A line connecting any two tin nodes must lie inside or define the convex hull.

You can use the polygons created with the HULL option as a clip coverage with the Clip tool to ensure that all coverage features are within the zone of interpolation of a tin.


The tin you want to convert.


Choose how you want to calculate slope values.

Percent – computes slope in percent, ranging from 0 to infinity and adds the attribute PERCENT_SLOPE to the PAT with the Poly option and to the AAT with the Line option.

Degree – computes slope in degrees, ranging from 0 to 90 and adds the attribute DEGREE_SLOPE to the PAT with the Poly option and to the AAT with the Line option.


Percent – computes slope in percent, ranging from 0 to infinity and adds the attribute PERCENT_SLOPE to the PAT with the Poly option and to the AAT with the Line option.


Degree – computes slope in degrees, ranging from 0 to 90 and adds the attribute DEGREE_SLOPE to the PAT with the Poly option and to the AAT with the Line option.


The Z-factor states how many ground units in your tin equal one elevation- or z-unit. It is possible that the ground units of a tin are in meters and the elevation units are in feet.

To get correct slope and surface area calculation results, enter a Z-factor to convert the elevation units of your Input tin to the same units of measure as its ground units. For example, the Z-factor to convert feet to meters is 3.281, and from meters to feet is 0.3048.

NOTE: The Z-factor you enter does not change the tin data.


Writes a light reflectance value that represents shaded relief for each triangle facet to the SHADE_INDEX item in the PAT.


Sets the Azimuth angle of the light source for the hillshading. The Azimuth is expressed in degrees from 0 to 360, measured clockwise from the north. The default is 315 degrees.


Sets the Altitude angle of the light source above the horizon for the hillshading. The Altitude is expressed in degrees, with 0 degrees at the horizon and 90 degrees directly overhead. The default is 45 degrees.


The coverage you will create. It will always be double-precision.


Choose the coverage type you want to create.

Poly – creates a polygon coverage and adds the items DEGREE_SLOPE or PERCENT_SLOPE, ASPECT, and SAREA to its PAT. Each triangle becomes a polygon.

Line – creates a line coverage and adds the items DEGREE-SLOPE or PERCENT-SLOPE, LSLOPE, RSLOPE, LASPECT, RASPECT, ZFROM, ZTO, and SFTYPE to its AAT. Each edge becomes a line.

Point – creates a point coverage and adds the item SPOT, storing z values, to its PAT. Each node becomes a point.

Hull – creates a polygon coverage with one or more polygons outlining the tin’s interpolation area.


Tin to Grid

Converts a tin to a grid by interpolation of mesh points.

Notes

Because interpolation of the Input tin surface occurs at regular intervals, some loss of information in the Output grid should be expected. How well the Output grid represents the Input tin is dependent on the resolution of the Output grid and the degree of the Input tin surface variation. Generally, as the resolution is increased, the Output grid more closely represents the Input tin surface. Because the Output grid is a cell structure, it cannot maintain the Hard and Soft breakline edges that may be present in the Input tin.

The tool interpolates cell z-values from the Input tin at the specified resolution or sampling interval to produce the Output grid. The Output grid cell z-values are interpolated from the tin using the specified Interpolation method.

The Quintic option is most appropriate when the tin nodes are relatively sparse. This can occur when the Output grid extent is set to a small region that contains only a few Input tin nodes. This can also occur when you are converting an entire tin that is relatively small in terms of its number of nodes and the nodes do not sufficiently represent the surface’s morphology. In this case, the Output grid may benefit from the smoothing effects of Quintic interpolation.

Alternatively, converting large tins with the Quintic option can take a very long time to execute. In addition, a large amount of disk space is required for temporary files during the conversion. Generally, Quintic interpolation on very large tins is unnecessary and wastes computing resources; use Linear interpolation instead.

Related Topics


The tin you want to convert to a grid.


The grid you will create.


Choose the type of Interpolation to use to interpolate the grid mesh point z-values.

Linear – uses the linear interpolation method. Use this method for tins of any size.

Quintic – uses the bivariate quintic interpolation method. Because this method is so resource- and time-intensive, we recommend it for tins with fewer than 200,000 points.


The Z-factor states how many ground units in your tin equal one elevation- or z-unit. It is possible that the ground units of a tin are in meters and the elevation units are in feet.

To get a meaningful and correct difference calculation, enter a Z-factor to convert the elevation units of your Input tin to the same units of measure as its ground units. For example, the Z-factor to convert feet to meters is 3.281, and from meters to feet is 0.3048.

The tin’s elevation units are multiplied by the Z-factor and the result is applied to the grid’s elevation units. The tin data remains unchanged.


A breakline is a linear feature that defines and controls the surface behavior of a tin in terms of smoothness and continuity. Breaklines are always maintained as linear features in a tin. Stereo-digitized features containing x,y,z values such as streams and shorelines containing an elevation attribute are often stored as breakline features.


The size of a single grid cell. The value displayed here is automatically calculated for you from the Input tin resolution.


The number of rows the grid will have. The number displayed is automatically calculated from the Cell size and Input tin extent.


The number of columns the grid will have. The number displayed is automatically calculated from the Cell size and Input tin extent.


Tin to VRML

Converts a tin to VRML format.

Notes

The Output VRML can be viewed by web browsers or viewers that support data in VRML 1.0 format.

The Symbology options Color and Gray are used to place a symbology definition for the tin in the Output VRML file. Color defines a hypsometric shade, and Gray defines a shaded relief.

In addition to normalizing x, y and z units, Z-factor can be used to apply vertical exaggeration to the output. The Z-factor is the number of ground x, y UNITS in 1 surface ZUNIT. The Input tin ZUNITS are multiplied by the specified Z-factor to adjust the Output VRML ZUNITS to another unit of measure. By default, a Z-factor of 1.0 is applied.

Related Topics


The tin you want to convert to VRML format.


Choose the type of Symbology definition you want to include in the Output VRML file. It is used by VRML browsers to render the Input tin.

Color – uses hypsometric shading.

Gray – uses shaded relief.


Color – uses hypsometric shading.


Gray – uses shaded relief.


The Z-factor states how many ground units in the Input tin equal one elevation- or z-unit. It is possible that the ground units of a tin are in meters and the elevation units are in feet.

To get correct conversion results, enter a Z-factor to convert the elevation units of your Input tin to the same unit of measure as its ground units. For example, the Z-factor to convert feet to meters is 3.281, and from meters to feet is 0.3048.

NOTE: The Z-factor you enter does not change the tin data.


The VRML file you will create.


Virtual Reality Modeling Language (VRML) is a data specification for 3-D worlds on the Internet.


Transform

Converts data from one coordinate system to another. It is often used to convert coverages created in digitizer units (most often inches) into the real-world units represented on the map manuscript. These real-world locations are represented by a particular projection; for example, the projection of your base map may be UTM with control point locations measured in meters.

To perform a transformation, you must be able to register at least two tics in your coverage to real locations. These real locations may be measured in feet or meters using the base map coordinate system, or they may be located at latitude-longitude intersections. If your locations reference degrees of latitude and longitude, then first use the Project Wizard to convert these control points into the coordinate system which corresponds to your base map, measured in feet or meters.

The transformation function is based on comparing the coordinates of the Input coverage tics with the coordinates for corresponding tics in the Output coverage. Only tics with matching Tic-IDs are used in the transformation.

The tool provides three Transformation methods:

  Affine

  Projective

  Similarity

We strongly recommend that you provide at least one more tic than the required minimum to determine the accuracy of the coordinate transformation, as expressed by the root mean square (RMS) error.

Transform provides an output report when it has finished processing that includes the RMS error for both input and output coverages. The report is available to you if you click Yes when asked to see the output messages.

Notes

Tics in the Input coverage and Output coverage do not have to be identical; only those tics whose IDs are common to both coverages will be used in the transformation.

AREA and LENGTH item values are updated to reflect the transformed coordinate system.

Features in the Output coverage will be replaced by the transformed features of the Input coverage.

The tolerances of the Input coverage will be transformed and retained in the TOL file of the Output coverage.

The position and size of Input coverage annotation subclasses are transformed in the Output coverage.

The tool copies existing section tables to the Output coverage. The relationship between the sections and the arcs will be maintained by the transform process.

Region information is maintained.

Since the default $ANGLE value is zero, label points that have not been rotated will remain unrotated after Transform. However, if the $ANGLE value of some labels are set, the tool will add the transform angle to the label angles.

Transform deletes item indexes. To create an item index, access the item from ArcCatalog.

Related Topics


The coverage whose coordinates you want to transform.


The existing coverage whose tics you want to use for the coordinate transformation.

NOTE: All other features will be replaced by transformed features from the Input coverage.


Choose the coordinate Transformation you want to perform.

Affine – requires at least three tics to transform coordinates. Use the affine transformation if you want to scale your coverage along the x- and y-directions to get the best fit. NOTE: This can potentially alter the shape of features; for example, a square may turn into a rectangle. and a circle may turn into an ellipse.
The affine transformation is commonly used to transform quad sheet maps in digitizer units to real world units, such as feet (State Plane) or meters (UTM).

Projective - requires at least four tics to transform coordinates. Use the projective transformation only to transform coordinates digitized directly off high altitude aerial photographs or off aerial photographs of predominantly flat terrain.

Similarity – requires at least two tics to transform coordinates. Use the similarity transformation if you want to enlarge or reduce your coverage, without changing the features’ shape. This method applies equal scaling along the x- and y-axes to ensure that a square remains a square, and a circle remains a circle.
The similarity transformation is commonly used to transform a large-scale map from digitizer units to real world units, such as feet (State Plane) or meters (UTM).


The Root Mean Square (RMS) error, or tic registration error, indicates how accurate the coordinate transformation is by measuring the difference between the location of the Output coverage tics and the transformed location of the Input coverage tics. Parameters such as the accuracy of the original data and the scale of the source map influence the RMS error. RMS states the error as a number of map units. The smaller the RMS error value, the more accurate the transformation. A value of 0.004 or less is desirable.


Aerial photographs are images shot from an airplane flying at an altitude of 500 to 5000 meters. They are typically obtained for clearly delimited areas, such as a forest stand or a municipality, in regular intervals to maintain a view of the current ground situation.


Affine transformation

Requires at least three tics to transform coordinates. If only two tics are matched, a similarity transformation will be applied. Use the affine transformation if you want to scale, skew, rotate or translate your coverage along the x- and y-directions to get the best fit.

NOTE: This can potentially scale the x-coordinates differently than the y-coordinates, which in turn may alter the shape of features; for example, a square may turn into a rectangle and a circle may turn into an ellipse. If only two tics in the Output coverage match tics in the Input coverage, a similarity transformation is performed.

The affine transformation is commonly used to transform quad sheet maps in digitizer units to real world units, such as meters (UTM) or feet (State Plane). It can also be used to perform plane reflections.


Similarity transformation

Requires at least two tics to transform coordinates. Also known as a Helmert, orthogonal, or two-dimensional linear conformal transformation. Use the similarity transformation if you want to scale, rotate or translate your coverage without changing the features’ shape. The similarity transform cannot be used to skew a coverage. This method applies equal scaling along the x- and y-axes to ensure that a square remains a square, and a circle remains a circle.

The similarity transformation is commonly used to transform a large-scale map from digitizer units to real world units, such as meters (UTM) or feet (State Plane). It can also be used to edgematch scanner output where a scanned map has been cut into several sections to fit on the scanner.


Projective transformation

Requires at least four tics to transform coordinates. Use the projective transformation only to transform coordinates digitized directly off high altitude aerial photographs or off aerial photographs of relatively flat terrain assuming that there is no systematic distortion in the air photos. The accuracy of the transformation will depend on the surface terrain being photographed, the angle between the camera and the ground, and the elevation from which the photograph was taken.


Union

Creates a new coverage by overlaying the polygons in the Union coverage with those in the Input coverage. Where their arcs intersect, they are split. Then all the arcs from both coverages are built into a new polygon coverage with label points. The User-IDs are set to the polygon internal number minus 1.

Region subclasses in either the Input or Union coverage are maintained in the Output coverage. Subclasses with identical names and attribute schemas are appended.

Join feature attribute tables

When checked, all items from both the Input coverage and Union coverage are copied to the Output coverage polygon attribute table (PAT). When there are duplicate items, only the Input coverage item will be copied. To see an example, click [image].

When unchecked, only internal numbers (<cover>#) from both coverages are copied to the Output coverage PAT. To see an example, click [image].

Notes

The Input coverage, Union coverage and Output coverage must have different names, even when in different workspaces.

Data model content inherited by the output

How the default fuzzy tolerance is calculated

Processing planar graphs

Example

Related Topics


In this example, Union creates a new region coverage by overlaying two sets of regions. The Input coverage contains regions A and B. The Union coverage contains regions C and D. The Output coverage contains all four regions.


Join all attributes


Join only internal numbers


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Feature attribute table items

Tics

Annotation

Projection file

Route-systems


The polygon coverage you will overlay with the Union coverage to combine their features.


The polygon coverage you will overlay with the Input coverage.


The coverage you will create.


Choose whether you want to Join feature attribute tables.

Checked – the tool transfers the attributes from the PATs of both coverages to the Output coverage.

Unchecked – the tool transfers only the <COVER># from both coverages to the Output coverage.


Update

Creates a new coverage by overlaying two sets of features, using the polygons of the Update coverage to cookie cut the features and attributes from the Input coverage. Attributes are updated and topology is rebuilt for the Output coverage.

Before updating, the following conditions must be met:

Item definitions past the User-ID must be the same for both coverages. This includes redefined items.

Annotation subclasses and their attribute definitions must be identical. Blank annotation subclasses are ignored.

Section subclasses and their attribute definitions must be identical.

Region subclasses with the same name must have the same attribute definitions.

Notes

New label point positions are generated for Output coverage polygons only when necessary. The User-ID for each polygon is equal to its old Input coverage User-ID, or Update coverage User-ID for updated polygons.

Before updating, you should make the User-ID values in the Input coverage differ from those in the Update coverage, otherwise duplicate User-IDs will be created in the Output coverage.

If the Update coverage contains nodes on its border that are coincident with nodes in the Input coverage, the Update coverage’s nodes are maintained. The only exception is if the Input coverage’s node contains data in the node attribute table (NAT) and the Update coverage’s node does not have an NAT.

How region subclasses are updated depends on the extent of the regions in Input and Union coverages. Consider these examples where Keep update border is checked:

  Input coverage has subclasses but Update coverage does not
  Update coverage has subclasses but Input coverage does not
  Both Input and Update coverages have subclasses

Annotation features are updated by identifying the set of Input coverage annotation whose lower-left starting points fall within an Update coverage polygon and deleting them. Then Update coverage annotation is appended for all annotation subclasses present.

Route-systems attached to update arcs are retained. Route-systems attached to input arcs are retained if they survive.

Data model content inherited by the output

How the default fuzzy tolerance is calculated

Related Topics


Data model content inherited by the output

The Output coverage inherits these data model contents from the Input coverage:

Tics

Projection file

Route-system subclasses


Input coverage has subclasses but Update coverage does not

 The Input coverage has a region subclass Forest, but the Update coverage does not. Consequently, a void area is created where the Update coverage overlaps the regions of the Input coverage.


Both Input and Update coverages have subclasses

 Both coverages have a region subclass Landuse. In this case, the region subclass Landuse features 1 and 2 of the Input coverage are replaced with region subclass Landuse feature 3 of the Update coverage.


Update coverage has subclasses but Input coverage does not

The Update coverage has a region subclass Owner, but Input coverage does not. The update subclass has two fully overlapping regions which are maintained in the Output coverage.


The coverage with features you want to update.


Choose the feature class from the Update coverage that you want to update.

Poly – polygons and PAT.

Poly & Line (Net) – polygons and arcs, PAT and AAT.


The coverage containing features that will replace the Input coverage features.


Choose whether you want to Keep the update border.

Checked – maintains the outside border of the Update coverage polygons in the Output coverage.

Unchecked – drops polygon boundaries along the outer edge of the Update coverage after the features and attributes are updated. This option is not recommended for region coverages because some output regions may not be maintained.


The coverage you will create.


Update IDs

Updates User-IDs in a coverage after they have been modified in a feature attribute table. The feature attribute table is used to determine the correct User-ID for each feature in the coverage. This value is recorded in all places where the feature User-ID is stored.

Notes

TABLES and INFO commands such as UPDATE, ADD and CALCULATE can be used to add or modify User-IDs in a coverage’s feature attribute table before Update IDs is used.

If the Create Polygon Labels tool has been used to create new label points for coverage polygons, the polygon User-IDs stored in the coverage PAT are not equal to the new label point User-IDs. Create Polygon Labels stores the new label points and their User-IDs in the LAB file. Update IDs may be used to change the label point User-IDs to be equal to the User-IDs stored in the polygon attribute table (PAT).

Use the Build tool to change the User-IDs stored in the PAT to be equal to the label point User-IDs.

There is no Node option because it is not necessary after updating User-IDs in the node attribute table (NAT).

Related Topics


The coverage you want to update.


Choose the feature class whose User-IDs you want to update.

Poly – updates polygon User-IDs.

Line – updates arc User-IDs.

Point – updates point User-IDs.

Anno.<subclass> – updates annotation User-IDs.

Note: Nodes do not need to be updated after updating User-IDs in the NAT file.


Visibility

Performs visibility analysis on an Input grid by determining how many observation points in a coverage can be seen from each region of the grid, or which regions can be seen by each observation point.

Items in the Input coverage feature attribute table can be used to control the visibility analysis. These items are: SPOT, OFFSETA, OFFSETB, AZIMUTH1, AZIMUTH2, VERT1, VERT2, RADIUS1 and RADIUS2. See Controlling the visibility analysis for more information.

The tool provides two Analysis methods:

  Frequency

  Observers

Notes

The visibility of each mesh point is determined by comparing the altitude angle to the mesh point with the altitude angle to the local horizon. The local horizon is computed by considering the intervening terrain between the point of observation and the current mesh point. If the point lies above the local horizon it is considered to be visible.

When a SPOT attribute item does not exist in the feature attribute table, Visibility uses bilinear interpolation to determine the elevation of each observation point. If the nearest Input grid mesh point to an observation point or vertex has the NODATA value, then Visibility will be unable to determine its elevation. In this case, the observation point will be excluded from the visibility analysis. A warning message will be given in the dialog area, and the visibility analysis will continue with the next observation point or vertex.

Intervening NODATA mesh points between the point of observation and other grid mesh points are evaluated as invisible, and do not obscure visibility.

Areas are calculated on the basis that the mesh points lie in the center of their associated polygon. Polygons representing mesh points on the edge of the grid extend beyond the mesh point by one half of the mesh-point spacing. In this way, polygon coverages created from adjacent grids form a continuous coverage when joined with the Append Wizard.

Key files can become quite large when the Input coverage contains a large number of observation points, or when the Input grid is large and represents an irregular terrain surface.

Potential preprocessing

How to perform an analysis of visual quality

Related Topics


Controlling the visibility analysis

It is possible to limit the region of the grid inspected by specifying any of the optional feature attribute items described below. You can specify observation point elevation values, vertical offsets, horizontal and vertical scanning angles, and scanning distances.

Nine items in the Input coverage feature attribute table (FAT) can be used to control the Visibility analysis. These items are:  SPOT, OFFSETA, OFFSETB, AZIMUTH1, AZIMUTH2, VERT1, VERT2, RADIUS1 and RADIUS2.

With the Point option, each observation point can have a unique set of observation constraints in the Input coverage PAT. With the Line option, every vertex along an input arc uses the same observation constraints contained in the arc’s record in the Input coverage AAT.

The definitions for these items can vary, as long as they are numeric (B, F, I or N). Whenever an item does not exist, the default values are applied.

The SPOT item specifies surface elevations for the observation points or vertices. When an item named SPOT exists in the Input coverage FAT, the SPOT values are used as the elevation of the observation points. If no SPOT item is present, the surface elevation for the observation points are interpolated from the Input grid using BILINEAR interpolation.

The OFFSETA item indicates a vertical distance in surface units to be added to the z value of the observation point. If OFFSETA exists in the Input coverage FAT, its value is added to the SPOT elevation (see above) or the z value interpolated from the Input grid surface. The OFFSETA value must be positive. If OFFSETA does not exist, the default value is 1.

The OFFSETB item indicates a vertical distance in surface units to be added to the z value of each mesh point as it is considered for visibility. If OFFSETB exists in the Input coverage FAT, its value is added to the surface z value of each mesh point when it is being analyzed for visibility. The value must be positive. If OFFSETB does not exist, it defaults to zero.

The AZIMUTH1 and AZIMUTH2 items specify horizontal angle limits to the scan. The sweep proceeds in a clockwise direction from AZIMUTH1 to AZIMUTH2. Values are given in degrees from 0 to 360, with 0 oriented to the north. If the AZIMUTH1 and AZIMUTH2 items do not exist in the Input coverage FAT, AZIMUTH1 defaults to 0 and AZIMUTH2 defaults to 360, implementing a full 360-degree sweep.

The VERT1 and VERT2 items specify vertical angle limits to the scan. The value of VERT1 sets the upper limit of the scan; VERT2 sets the lower limit. The VERT1 and VERT2 angles are expressed in degrees between 90 and -90 degrees. Positive angles are above the horizontal plane; negative angles are below. The horizontal plane (0 degrees) is defined by the z value of the observation point plus the value of OFFSETA. The default values are 90 for VERT1 and -90 for VERT2.

The RADIUS1 and RADIUS2 items limit the search distance when identifying areas visible from each observation point. Grid points beyond the RADIUS2 search distance are excluded from the analysis. Mesh points closer than the RADIUS1 search distance are not visible in the Output coverage but can still block the visibility of grid points between RADIUS1 and RADIUS2. The default RADIUS1 distance is zero; the default RADIUS2 distance is infinity.

By default, the limiting distances RADIUS1 and RADIUS2 are interpreted as three-dimensional line-of-sight distances. To ensure that the slope distance is calculated correctly, both the ground UNITS and surface ZUNITS must be in the same unit of measure. To process RADIUS1 and RADIUS2 as two-dimensional planimetric distances, insert a negative sign (-) in front of the values. For example, if RADIUS1 is set to -1000 and RADIUS2 is set to -9000, Visibility analyzes the regions of the surface between 1,000 and 9,000 ground UNITS measured planimetrically from the observer.

Default settings for the visibility controlling options


Default settings for the visibility controlling options

Option           Default setting
SPOT      estimated using BILINEAR interpolation
OFFSETA                1
OFFSETB                0
AZIMUTH1               0
AZIMUTH2             360
VERT1                 90
VERT2                -90
RADIUS1                1
RADIUS2            infinity


A key file is created with the Observers option, when the output is a polygon coverage. It is named <Output coverage>.OBS, and contains one record for each observation point visible to each Output coverage polygon. The key file contains two items:

ITEM NAME                WIDTH  OUTPUT  TYPE  N.DEC
<Output coverage>-ID         4       5     B     -
<Input coverage>#            4       5     B     -


Potential preprocessing

Determining visibility is a computer-intensive process. The processing time is highly dependent on the grid resolution. For the purposes of preliminary studies, you may want to use the Arc LATTICERESAMPLE command to reduce the number of Input grid mesh points.

In some cases, there may be too many or too few vertices along the Input coverage arcs. Use the Generalize Lines tool to adjust the interval between each or selected Input coverage arc.

If the Input grid contains undesirable noise caused by sampling errors, you may want to smooth the grid by using the Arc FILTER command with the LOW option before running Visibility.


How to perform an analysis of visual quality

The Observers analysis method can be used to perform an analysis of visual quality. For example, you can determine the visual quality of all locations on a surface by positioning an observation point at each significant visual feature within the extent of the grid. Such points might include the city dump, the auto salvage yard, the local parks and each of the power transmission towers in the region.

1	Run the Visibility tool with the Observers option for Analysis method.

2	Use the key file to select those polygons that can see each visual feature.

3	Use the CALCULATE command to accumulate positive or negative scores depending on each observation point’s visual quality and weight.

After all observation points have been considered, those polygons with the best scores will have the best visual quality.


The grid you want to analyze for visibility.


The coverage with points or lines used as observation points.


The feature classes available as observation points:

Point – representing observation points

Line – every node and vertex along each Input coverage arc is used as an observation point. The Output coverage VISIBLE-CODE values give the number of nodes and vertices that are visible to each polygon.


Choose the visibility analysis method you want to use.

Frequency – records the number of times each output polygon or grid cell can be seen from/by input observation points.

Observers – records the <Input coverage># of each observation point that can see each output polygon or grid cell.


The coverage or grid you will create.


Choose what type of Output dataset you want.

Poly – creates a double-precision polygon coverage, where each polygon identifies areas with common visibility characteristics.

Grid – creates an integer grid, where each grid cell contains either the number of times the cell is visible (Frequency option), or a binary-encoded value identifying which Input coverage observation points can see the cell (Observers option).


Frequency method

The output will only record the number of times each output polygon or grid cell can be seen by the Input coverage observation points. When the output is a polygon coverage, the frequency of observation will be recorded in an item named VISIBLE-CODE in the polygon attribute table (PAT); no key file will be created. When the output is a grid, the observation frequency will be recorded in the VALUE item in the value attribute table (VAT). Input grid NODATA mesh points are indicated in the output VISIBLE-CODE or VALUE item with the value -9999.


Observers method

This method is only available with the Point Feature class option and when the number of observation points is 16 or less. The output will contain a binary-encoded value which can be decoded to identify the <Input coverage># of each observation point that can see each output polygon or grid cell. When the output is a polygon coverage, the encoded value will be recorded in an item named VISIBLE-CODE in the polygon attribute table (PAT). In addition, an INFO key file named <Output coverage>.OBS is created. The key file records the <Input coverage># of each observation point that can see each Output coverage polygon.

When the output is a grid, the encoded value will be recorded in the VALUE item in the value attribute table (VAT). In addition to the standard items VALUE and COUNT in the VAT, a new item named OBSn will be created in the VAT for each observer n in the input point coverage. The OBSn item will be assigned a value of 1 if the grid cell can be seen by observer n, or a value of 0 if it cannot be seen.


Volume

Calculates the area and volume of a tin.

Base z-value specifies the base elevation from which to begin calculating volumes. The tool uses linear interpolation to calculate the area and volume of those portions of the Input tin surface lying between the specified Base z-value and the highest point in the Input tin. Specify the Base z-value in surface z-units after Z-factor adjustment.

The use of a Z-factor is essential for correct volume calculations when the surface z-units are expressed in a different unit of measure than the ground units.

Required pre-processing for non-convex tins

Calculating correct volumes requires that the boundary of your tin is properly defined. If the extent of the data used to create Input tin forms a non-convex shape, you must use the Create Tin Wizard with a Clip surface feature to build a non-convex tin. Otherwise, the Volume tool calculates the total volume of all tin triangles, including those required to create the convex tin.

Notes

Output table item definitions and descriptions

The volume is calculated between the Base z-value and the maximum z-value in the tin. A Base z-value greater than ZMAX results in a volume of zero. The following diagrams compare how volume is calculated with different Base z-value settings. The shaded areas indicate the regions used for volume calculations.

If you do not want the volume calculations to be standardized, specify a Z-factor of 1; the input z-units will be maintained.

The use of a z-factor does not modify the original data.

To calculate the volume below a given z-value, specify a Z-factor of -1 and give the Base z-value as a negative value. This technique can be used to calculate the volume of a tin representing a reservoir. A polygon representing the reservoir shoreline should be specified as a Hardclip surface feature when building the tin with the Create Tin Wizard.

Related Topics


The Output table contains nine items defined as follows:

NAME   WIDTH   OUTPUT   TYPE   N.DEC

TIN       32     32       C      -
ZMIN       4     12       F      3
ZMAX       4     12       F      3
DATUM      4     12       F      3
AREA       8     18       F      5
VOLUME     8     18       F      5
UNITS     32     32       C      -
ZUNITS    32     32       C      -
ZFACTOR    4     12       F      3

TIN - the name of Input tin.

ZMIN - minimum Input tin z-value after any Z-factor adjustments.

ZMAX - maximum Input tin z-value after any Z-factor adjustments.

DATUM - specified Base z-value.

AREA - planimetric area of the surface at the specified Base z-value in ground units.

VOLUME - three-dimensional volume of the surface in ground units.

UNITS - Input tin ground units.

ZUNITS - Input tin surface z-units before Z-factor adjustments.

ZFACTOR - specified or program calculated Z-factor value.

The returned ZMIN, ZMAX and VOLUME values include any Z-factor adjustments used to convert the Input tin z-units.


The tin whose area and volume you want to calculate.


The elevation from which to begin calculating volumes. The volume is calculated for those parts of the tin that lie between the Base z-value and the maximum elevation. The listed elevation range, given in the Min and Max z-value, will help you determine a valid value.


Displays the unit of measure for your tin’s elevation. Available units of measure are:

m (meters)

mm (millimeters)

cm (centimeters)

km (kilometers)

ft. (feet)

yd. (yards)

mi. (miles)

Undefined units


The Z-factor states how many ground units in your tin equal one elevation- or z-unit. It is possible that a tin’s ground units are in meters and its elevation units are in feet. To get a meaningful and correct result, use a Z-factor to convert the elevation units of your input tin to another unit of measure. For example, the Z-factor to convert feet to meters is 0.3048, and from meters to feet is 3.2808.


The table containing area and volume statistics.

NOTE: If the Output table already exists, a new record is added to it.


The tin’s minimum elevation. It is the lowest possible Base z-value.


The tin’s maximum elevation. The volume is calculated between this value and the Base z-value.


VPF to Coverage

Converts an untiled VPF coverage or VPF tile to a coverage or a VPF table to an INFO table.

Notes

Full VPF pathnames must be specified with Input VPF.

Pathnames are specified as vpfDatabase\vpfLibrary\vpfCoverage, or vpfDatabase\vpfLibrary\vpfCoverage\vpfTile when using the Cover option.

Pathnames are specified as vpfDatabase\vpfLibrary\vpfTable when using the Table option.

If the VPF coverage was created using the Coverage to VPF tool with the Convert extra tables option selected, then the Output coverage will be identical to the input VPF coverage.

VPF coverages with multiple linear feature classes will be translated into ArcInfo coverages with route subclasses. Multiple area feature classes will be converted into region subclasses. Text, connected node, and point feature classes will be translated into INFO tables that can be related to the appropriate ArcInfo coverage FAT. Complex feature classes will also be converted into INFO tables.

Conversion control file information.

Related Topics


Specify what type of data will be converted.

Coverage or Tile - input can be either a VPF coverage or VPF tile.

Table - input is a VPF table.


The name of the VPF table, untiled coverage, or tile to be converted. The full pathname must be specified.


A file that can be used to ignore specific VPF feature classes or three dimensional coordinates during translation.


Choose if you want to convert all files to VPF or only those needed to create a VPF coverage.

Checked – converts all available coverage or table files to VPF format. Use this option if the VPF coverage was created with the Coverage to VPF tool.

Unchecked – converts only those coverage files needed to create a VPF coverage. Use this option, if you do not want to convert the VPF coverage back to ArcInfo format.


The name of the ArcInfo table or coverage that will be created.


The name of the VPF tile that is to be converted. If the VPF coverage is not tiled, the list will be blank and disabled.


Conversion Control File Format

Command Syntax
/* comment line
/* Start of import section.
Import
Global Commands
END

Control File Commands

Global Commands

COLUMNBECOMES <vpf_item> <info_item> <info_item_type> <width> <output_width> {dec_places} - allows the user to modify item types when importing table columns.

FEATURETABLE ALL IGNORE :  ignores all VPF feature tables when importing a VPF coverage into ArcInfo format.  When this command is used only point and line geometry will be imported from the original VPF data.  The resulting ArcInfo coverage is built for line topology only.

PRIMITIVEITEM ALL :  appends all primitive items in the original VPF data to the appropriate ArcInfo feature class table.  Tile-id’s of each feature and tile-id’s of any features referenced in the imported table will also be added to as items to the ArcInfo feature class table.  This command effects the items created in the arc attribute tables (AAT’s) only.

SET NULL <vpf_table> <item> <info_null_value> - allows the user to import a null value as a discrete value. If VPFIMPORT is used without a SET NULL statement, VPF null values will be mapped to these default INFO null values:

S	Short integer	    -9999
I	Long integer	-999999
F	Short float	-999999
R	Long float  	-999999

TIN <tin_name | IGNORE> - converts VPF 3-D coordinates into the specified ARC/INFO TIN or will IGNORE 3-D coordinates during conversion. If this statement is not implemented, the default is to translate 3-D coordinates into a TIN with the name <cover_name>_tin.

VDT IGNORE - allows the user to ignore the importation of the Value Description Table (VDT).

Feature Class Command

FEATURECLASS <vpf_feature_class> IGNORE - allows the user to ignore specific VPF feature classes when importing a VPF coverage into ARC/INFO format.

<vpf_feature_class> - the feature class to be ignored. Valid VPF feature classes are <EPOINT | CPOINT | LINE | AREA | TEXT | COMPLEX>.

IGNORE - required keyword.


VPF to Geodatabase

Converts a feature class stored in a VPF coverage to a new feature class in a Geodatabase and assigns it the ESRI Simple Feature behavior class.

When you import VPF coverages, you create a new standalone feature class, a new feature dataset and feature class, or a feature class in an existing feature dataset. In the first two cases, you have to define a spatial reference.

If your VPF coverage has a defined projection, the tool will automatically create the new feature class with the same projection, unless you specify otherwise. If you do choose to import the data into a different projection than the source data is in, the features will automatically be projected.

Because all feature classes in a feature dataset share the same spatial reference, you must only specify a new spatial reference when loading the first feature class or when creating the feature dataset in ArcCatalog.

A suggested grid size is given based on the spatial reference, average feature size, and number of features in the input coverage. The suggested grid size is only an approximation. You can determine the optimum grid size for any feature class by examining the data and the needs of the application querying it.

When you convert data from one format to another, a question arises about how data of a specific type maps from one format to the other. Importing data into the geodatabase is no exception. In this case, how both the spatial type and the attribute field type map from one data type to another must be considered. For each geodatabase field type, the field itself is persistently stored in the database differently depending on which RDBMS stores the geodatabase. All feature class types and attribute item types in VPF coverages are mapped to geometry and field types in the geodatabase

The tool checks the item names in the input feature class attribute table for any characters or words that are illegal in the output table, and automatically changes them. You can view all the settings, and make any desired changes, by clicking Change Settings…. You may also choose to not include certain columns from the input table in the new Geodatabase table.

Notes

Duplicate table and feature class names are not permitted in a Geodatabase. The tool will check for duplicate names once a Geodatabase is selected. This process may take some time, depending on the size of the Geodatabase you specify and whether you are using SDE or Access.

In the geodatabase, annotation is not a geometry type, but a feature type. While VPF coverage features are imported into feature classes that store ESRI simple features with geometry types of point, line, or polygon, annotation is stored in feature classes that annotation feature types. If you import a VPF coverage annotation feature class into the geodatabase using one of the data loading tools or wizards, these annotations are stored as simple point features, and their text and symbology are not converted. A different process exists for converting VPF coverage annotation to the geodatabase. This process is described in Chapter 7, ‘Managing annotation’ of the Building a Geodatabase guidebook.

A SQL query may be used to limit the number of features being converted using the attributes of the currently selected feature class. Queries are not saved with the contents of the tool when the Save option is used. Queries may be saved using the Save option in the Query Builder.

The name for an output feature class cannot begin with a numeric character.  If this occurs the leading numeric character(s) will be dropped.

Spatial Reference and Domain extents

Spatial index grid

Related Topics


The name of the VPF coverage to be converted to a Geodatabase feature class.


The VPF coverage feature class you want to convert.


The name of the Geodatabase that will contain the dataset with the new feature class.


The name of a new or existing dataset that will contain the new feature class in the specified Geodatabase.


The name of the feature class to be created.

The feature class name cannot begin with a numeric character.


The settings that will be used during the conversion. Click the Change Settings… button to modify them.

Spatial reference: The output coordinate system determined from the input coverage feature class. The projection will be copied from the coverage, and the spatial domain calculated.

Grid size: The spatial index grid is a two-dimensional grid system that spans a layer, like the locator grid you might find on a common road map. It is used to quickly locate features in a dataset that might match the criteria of a spatial search.

Item names: Shows whether input item names have been modified or deleted. INFO  files allow characters in column names that other databases do not. The tool finds any illegal characters or reserved word field names in the input table, and corrects them for the output table.

Query: A SQL where clause that is used to create a selected set. Only the selected set will be converted to a feature class. If no expression is given, all features will be converted.

Keyword: A keyword that references database storage parameters on an SDE server. When loading data into an SDE Geodatabase, you can specify a configuration keyword. For more information on creating SDE keywords, see the SDE Administration documentation.

Geometry: M and Z values must be created at the same time as a feature class or feature dataset is created, as they can not be subsequently added. If the Enable M values on the output is checked the output feature class will have linear measurement (M) values. If you do not want your new feature class and/or feature dataset to contain M values, uncheck this option.


Click to modify the Output settings.


A query that is used to limit the features being converted from the input feature class. Click the Query Builder button on the right to build a query. Queries are not saved with the contents of the tool when the contents are saved to a file. Use the Save option in the Query Builder to save queries. Queries may then be loaded into the Query Builder when necessary.


Click to start the Query Builder which is used to interactively build a SQL query that will be used in the VPF to geodatabase conversion.