topic Re: delete part/ring of a multipart polygon feature in ArcGIS Pro Questions

delete part/ring of a multipart polygon feature

RamB — Fri, 02 Sep 2022 18:38:08 GMT

HI,

I have thousands of polygons that are multipart, I would like to delete parts of this polygon And I know which part i want to delete from the list of parts of a multipart polygon.

Is there anyway to delete specific parts of a multipart polygon ? I would like to automate this if not tool is available already. I show this in a picture. The full filled polygons in the image are created by manual deleting inner parts/rings from the hollow polygons you see in the image. There are too many such polygons for me to manually delete them. So any advice is welcome.

Thank you.

Re: delete part/ring of a multipart polygon feature

DanLee — Fri, 02 Sep 2022 19:36:56 GMT

If all the parts you want to delete are inner rings, i.e. polygon holes, you can try Eliminate Polygon Parts tool with Contained option.

https://pro.arcgis.com/en/pro-app/latest/tool-reference/data-management/eliminate-polygon-part.htm

Re: delete part/ring of a multipart polygon feature

RamB — Fri, 02 Sep 2022 19:57:05 GMT

Thank you. I already tried that. It has no effect. neither with contained or without containted check box.

Re: delete part/ring of a multipart polygon feature

DanLee — Fri, 02 Sep 2022 20:34:25 GMT

I am surprised. Could you show me how you ran the tool? Or you can share a few polygons so I can test. Thanks.

Re: delete part/ring of a multipart polygon feature

RamB — Sat, 03 Sep 2022 06:25:56 GMT

Here I attach a small sample. Thank you Dan

Re: delete part/ring of a multipart polygon feature

JoshuaBixby — Sat, 03 Sep 2022 18:05:38 GMT

I just tested Eliminate Polygon Part (Data Management)—ArcGIS Pro | Documentation with the uploaded sample data, and it worked as expected, i.e., the holes were removed. Make sure to specify a condition and appropriate value because leaving all the optional parameters empty won't result in anything being removed.

Re: delete part/ring of a multipart polygon feature

DanLee — Sat, 03 Sep 2022 18:23:43 GMT

Thanks for the sample data. This is how I ran and the holes were removed. You just need to specify an area larger than any holes.

Re: delete part/ring of a multipart polygon feature

JoshuaBixby — Sat, 03 Sep 2022 21:46:16 GMT

I find using percent of area and specifying 99% (the maximum allowed value) is simpler because one doesn't have to know any of the actual areas before running the tool.

Re: delete part/ring of a multipart polygon feature

RamB — Mon, 05 Sep 2022 13:29:39 GMT

Thank you Dan and Joshua. I tried a value for the area and it worked. It was kind of trial and error. So for now, I will accept Joshua's answer as it gives a more general approach. Thank you Dan.

Re: delete part/ring of a multipart polygon feature

DanLee — Mon, 05 Sep 2022 15:54:12 GMT

Absolutely! Using a very high percentage makes sense for your case. 🙂