Im using ArcMap 10.3

I have a large feature class of Archaeological surveys that I need to Spatial Join to a target feature class of buffered work locations to find locations that are Completely Within a survey. This is part of a large model I have created for our team, but my coworker noticed it is returning some join features that do not contain the target features. What's more strange, is that when I switched the join option to just Within, which should be less limited in scope, these false positives disappear, although now I am left with other unwanted target features where work areas and surveys just partially overlap.

What could cause this strange error?

I have run the repair geometry tool on both feature classes involved. Are there other geometry errors that could be causing this?

enter image description here

The image above shows the two work areas that are falsely returning information as if they were entirely within the survey area in orange.

  • 1
    What are the coordinate systems of each of the feature classes involved? – smiller Jun 13 '19 at 18:59
  • Coordinate Systems are both UTM Zone 11 – Dylan Warburg Jun 13 '19 at 19:14
  • 1
    DPatterson pointed out on GeoNet that the issue appears to be that Completely Within is considering the full extent of the Multipart Feature. I have switched to Within Clementini which for some reason eliminates these free floating matches. It is slightly more selective than Within, by eliminating features that only touch the boundary, but we will now have to select and remove cases of partial overlap. – Dylan Warburg Jun 13 '19 at 19:25
  • 1
    What about exploding the multipart to singlepart? – smiller Jun 13 '19 at 19:39
  • Whenever I get strange results from a geoprocessing tool I first run repair geometry on all the inputs resources.arcgis.com/en/help/main/10.2/index.html#//… issues like non-simple polygons (hourglass/bowtie) or incorrect ring orientations can cause havoc with overlay operators like spatial join. – Michael Stimson Jun 14 '19 at 2:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.