Dissolving a boundary

Dissolve combines shapes that contain the same value for a selected attribute. The resulting output is a layer that contains the newly combined shapes with each shape represented as a layer record.

  1. From the Analysis menu in the Focus window, click Dissolve.
  2. In the Dissolve window, choose a file from the File list in the Input area. If a file is not listed, click Browse, locate and select a file, and click Open. If you choose Active Layer, the dissolve is performed on the current layer.
  3. In the Output area, enable one of the following options:
    • Display: displays the results without saving the new layer
    • Save: saves the new layer in the project. Choose a file from the File list box and choose a layer from the Layer list box.
    • If you want to display the results in the view pane, enable the Display saved results check box.
    • If you want to use only the selected records, enable the Dissolve selected shapes only check box.
  4. In the Dissolve Option window, enable one of the following options:
    • Only adjacent shapes: combines all shapes that share a common border and contain the same value for the selected attribute or RST style
    • All shapes: forms one record for all the shapes on the layer that contain the same value for the selected attribute or RST style
    • If you want to combine the adjacent pixels that are diagonal to each other and that contain the same value for the selected attribute or RST style for thematic rasters, enable the Pixels that meet at a diagonal check box.
  5. In the Dissolve Method area, enable one of the following options:
    • Representation Values: removes boundaries between shapes that contain the same key for the representation of the layer
    • Attributes: removes boundaries between shapes that contain the same attribute values
  6. In the Based on column, enable the check box next to the attributes you want to include. If you want to add a field containing the number of shapes combined to form each record in the output, enable the Add a count field check box.
  7. Click OK.

For information about adding function or statistic fields to the output Attribute Manager, see Adding function fields to output layers.

  1. Adding function fields to output layers
Parent topic: Spatial analysis
Previous topic: Working with the Attribute Manager
Next topic: Working with shapes

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