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Identity Tool

January 28 2010 | 0 comments
Categories: ArcGIS Methods


I have two layers, one a parcels layer, another a "general" zoning layer. To explain the "general" part I will use an example - For Single Family a polygon has been drawn across a large area where single family residential exist. Other polygons are commercial for commercial areas, industrial for industrial areas, etc. I need to use the identity tool to populate a field in the parcels layer to correspond to the zoning area they belong. This way each parcel feature will have a field showing their zoning designation. Now here's my problem - some of the "general" zoning areas slightly overlap parcels that do not belong to that zoning area. The overlap is very slight, however I am afraid when I run the identity, a parcel's zoning designation may be wrong. Does the identity tool work in the way that the parcel will take the attributes of the area with the majority coverage. For example, if a parcel is mostly covered by a residential area but slightly covered by a commercial would it automatically take a residential designation? Thanks.

Mapping Center Answer:

The Identity, Union and Overlay overlay tools in ArcGIS will create new feature output for polygon-on-polygon overlay and there is no way to moderate where the new polygon outliens will be -- they are dictated by the input.  Instead try using the Spatial Join tool so that you are simply appending attributes.

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