Dissolve (Coverage)

This tool only works with an ArcInfo license and will only be available in ArcToolbox if you have installed ArcInfo Workstation.

Creates a new coverage by merging adjacent polygons, lines, or regions that have the same value for a specified item.


Illustration

Dissolve illustration

Usage tips

Syntax

Dissolve_arc (in_cover, out_cover, dissolve_item, feature_type)
Parameter Explanation Datatype
Input Coverage (Required)

The coverage containing features to be dissolved.

Coverage
Output Coverage (Required)

The coverage to be created.

Coverage
Dissolve Item (Required)

The item in the in_cover feature attribute table that is used to dissolve features.

  • Dissolve_item—An item name will be used to perform the dissolve. The item may be a redefined item.
  • #ALL—All items past the Cover-ID in the PAT, AAT, or region subclass PAT will be used as a single dissolve_item. If there are no items past the Cover-ID, then the Cover-ID will be used.

ArcInfo Item
Feature Type (Optional)

The feature classes to be preserved in the out_cover:

  • POLY—Polygons will be dissolved; an AAT will not be created for the out_cover. This is the default option.
  • LINE—Nodes will be dissolved; a PAT will not be created for the out_cover.
  • NET—Polygons will be dissolved, and both a PAT and AAT will be created for the output coverage.
  • REGION.subclass—Region subclass will be dissolved, and all existing attributes of the in_cover will be maintained in the output coverage.

String
Data types for geoprocessing tool parameters

Script Example

# Dissolve vegetation coverage features into unique regions

# Create the Geoprocessor
import arcgisscripting
gp = arcgisscripting.create()

# Local variables...
workspace = "C:/project93/data/"
vegtype = "vegtype"
veg_holland95 = "veg_holland95"

try:
    # Set the current workspace (to avoid having to specify the full path to the feature classes each time)
    gp.workspace = workspace

    # Process: Dissolve coverage features...
    gp.Dissolve_arc(vegtype, veg_holland95, "HOLLAND95", "region.vegtype")

except:
    # If an error occurred when running the tool, print out the error message.
    print gp.GetMessages()

See Also

  • Dissolve (Data Management)
  • Aggregate Polygons (Coverage)
  • Aggregate Polygons (Data Management)
  • Eliminate (Coverage)