topic Centroids in merged /multi-part polygons in ArcGIS Pro Questions

Centroids in merged /multi-part polygons

Emma_Cunliffe — Fri, 05 May 2023 14:10:06 GMT

Hello

Ideally using ArcGIS Pro, but if not, then using the latest version of ArcMap:

I have received a file with numerous multi-part polygons that have been merged to share a single line of an attribute table. I need the centroids for each part of the polygon - not a single centroid in the middle of all of them which will inevitably be inside none of them (so not this: https://support.esri.com/en-us/knowledge-base/how-to-find-the-centroid-between-multiple-polygon-featu-000018271#:~:text=The%20following%20steps%20describe%20how%20to%20find%20the,configure%20the%20following%20settings..%20Specify%20the%20polygon%20layer.)

Is there a way to generate centroids for each part of each polygon, or would I need to unmerge them first?

Thank you

Re: Centroids in merged /multi-part polygons

DanielFox1 — Fri, 05 May 2023 14:40:38 GMT

Hi @Emma_Cunliffe

You will have to unmerge the multipart polygon and then generate a centroid for each part, as you have already identified that if you create a centroid for the merged multipart polygon it will create one in the centre of the layer or wherever that centroid would be.

You could use the following tool afterwords to have as an overlay of the merged multipart polygon

Feature To Point (Data Management)

Re: Centroids in merged /multi-part polygons

DanPatterson — Fri, 05 May 2023 21:54:04 GMT

Multipart To Singlepart (Data Management)—ArcGIS Pro | Documentation

does the task of converting to singlepart.

You can get the centroids from that file

Calculate Geometry Attributes (Data Management)—ArcGIS Pro | Documentation