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Select neighboring polygons that have same attribute

July 14 2011 | 0 comments
Categories: Map Data

Is there a tool that will select or identify neighboring polygons that have the same attributes? For example, our surficial geologic maps have multiple units that are classified as Quaternary. These units are further classified into subdivisions of the Quaternary, resulting in at least 10 - 15 units that have a unique classification that will be symbolized on the map. One option is to visually inspect the map. However, in high feature density areas where colors are similar between units, this task is a bit of a challenge (see attached image for example).

Mapping Center Answer:

One solution is to dissolve the polygons based on the attribute that you are interested in (e.g. Quaternary) and then use a spatial join oir an overlay operation (e.g., Union) to identify the features in the original dataset that are in the dissolved polygons.  However, you could also use a selection by attribute operation using the operator "LIKE" to select those polygons that have an attribute that includes "Quaternary". This will select all polys with those attribute.  The challenge is to then select the adjacent ones.  It is hard to offer further help on this without knowing what your full workflow is as there are a number of ways to "skin this cat", so to speak.

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