topic Re: Spatial Joining 2 polygon layers based on centroids in Python Questions

Spatial Joining 2 polygon layers based on centroids

TheoFaull — Wed, 19 Oct 2016 14:30:26 GMT

Hello,

The spatial join tool in ArcMap is rather limited. It only looks for intersecting polygons or 'fall completely inside of' polygons:

I want to spatially join a polygon to another polygon based on whether the centroid falls within it. Is there another way to do this? Python script maybe?

Re: Spatial Joining 2 polygon layers based on centroids

DanPatterson_Retired — Wed, 19 Oct 2016 14:36:14 GMT

Why not produce the centroid layer, then spatially join it to the other layer.

Re: Spatial Joining 2 polygon layers based on centroids

LesiMai3 — Wed, 19 Oct 2016 14:41:18 GMT

Hi Theo,

Under the select by location tool, there is an option to select features that have their centroids falling in the source layer feature.

Lesi

Re: Spatial Joining 2 polygon layers based on centroids

TheoFaull — Wed, 19 Oct 2016 14:58:56 GMT

I know, and that's useful for Selecting. But I'm looking to do a spatial join. I have hundreds and thousands of shapes within each layer, all with multiple attribute variation. Lesi Mai‌

Re: Spatial Joining 2 polygon layers based on centroids

TheoFaull — Wed, 19 Oct 2016 15:00:20 GMT

Hmmm yes I could create a whole new centroid layer... Could you tell me (or point me in the right direction) how to go about this? I only have a basic license bear in mind. Dan_Patterson‌

Re: Spatial Joining 2 polygon layers based on centroids

LesiMai3 — Wed, 19 Oct 2016 15:12:01 GMT

Sorry for misreading your question.You can use calculate geometry to get the xy coordinates of the centroid and make an xy event layer based on the coordinates.

Re: Spatial Joining 2 polygon layers based on centroids

DanPatterson_Retired — Wed, 19 Oct 2016 15:18:52 GMT

Sadly FeatureToPoint requires an advanced license... so as suggested below, But everyone has Add XY coordinates, then you just add the table back in (File, Add Data, Add XY data) and save it back out to its own feature class.

Such unnecessary steps. You can do this by other means, but the workflow is only 10s of seconds to complete

Re: Spatial Joining 2 polygon layers based on centroids

DarrenWiens2 — Wed, 19 Oct 2016 16:25:52 GMT

The Spatial Join geoprocessing tool has many more options than the menu spatial join tool, one of which is HAVE_THEIR_CENTER_IN.

Re: Spatial Joining 2 polygon layers based on centroids

TheoFaull — Wed, 09 Nov 2016 10:34:02 GMT

dkwiens‌ thank you so much. This is the answer I was hoping for! You've saved me having to go through all the steps of converting polygons to XY event layer points, then joining that to my join layer.

Cheers.