How To: Calculate the percentage of a polygon boundary that does not fall within a specified distance of other polygons
Instructions provided describe how to calculate the percentage of a polygon boundary that does not fall within a specified distance of other polygons. For example, how to calculate the percent of the city boundary that does not fall within 1000 feet of certain attractions.
- For buffer features, use the Dissolve All option to make one feature. For more information on using the Buffer tool, see ArcGIS Desktop help topic: Creating Buffers.
- Use the Merge tool to merge the buffers of schools, churches and parks into one shapefile. Call the output 'Buffer_Merge.shp'.
- Dissolve the feature class. Uncheck the option to Create Multi-part features.
- In ArcMap, export the boundary layer to a new shapefile. Add the newly created shapefile to the map.
- Start an edit session. Set the target to the new boundary shapefile.
- In the Table of Contents, click Selection (or List by Selection). Right-click the Buffer_merge_Dissolve layer and select 'Make this the only selectable layer'.
- Use the black arrow tool from the Editor toolbar and select the BufferMergeDissolve feature.
- From the Editor drop-down list, select Clip. Select 'Discard the area that intersects' and click OK.
- Stop editing and save the edits.
- Open the attribute table of the clipped boundary layer. Navigate to Options > Add Field and type 'Area' into the Name field. Set the type to Double.
- Right-click the new field heading and select Calculate Geometry.
A message may display regarding calculation occurring outside of an edit session. Dismiss the message by clicking Continue.
Select the Area property from the drop-down list, and select the Units desired. Click OK.
- Repeat steps 10 and 11 for the original boundary layer.
- Compare the clipped and whole boundary layer areas.