topic Re: The difference between polygons in ArcGIS Pro Questions

The difference between polygons

MauriceMitchell — Wed, 29 Apr 2020 17:22:02 GMT

I have to separate polygon layers, layer 1 and layer 2. The polygons in layer 2 don't completely cover the polygons in layer 1, therefore, I'd like to create a layer 3 that are polygons that aren't overlapped. Also, I'm using ArcGIS Pro 2.4 if that matters.

Re: The difference between polygons

Robert_LeClair — Wed, 29 Apr 2020 17:28:10 GMT

You could try the Symmetrical Difference GP tool listed here.

Re: The difference between polygons

JoeBorgione — Wed, 29 Apr 2020 17:32:01 GMT

Cool tool Robert LeClair‌; the antithesis of intersect. I've never noticed it before....

Re: The difference between polygons

Robert_LeClair — Wed, 29 Apr 2020 17:44:29 GMT

It's a great (and unseen) tool for such a workflow! Cheers!

Re: The difference between polygons

Katie_Clark — Wed, 29 Apr 2020 17:47:33 GMT

I was going to suggest the Erase tool as well, but looks like that also requires an advanced license. I'm not sure if that's a restriction for the OP, but just out of curiosity, any suggestions that wouldn't require that?

Re: The difference between polygons

Robert_LeClair — Wed, 29 Apr 2020 17:51:25 GMT

I found the following that describes the differences:

Erase - This tool creates a feature class from those features or portions of features outside the erase feature class.
Symmetrical Difference - This tool creates a feature class from those features or portions of features that are not common to any of the other inputs.

Re: The difference between polygons

Katie_Clark — Wed, 29 Apr 2020 17:55:32 GMT

Right, but I was just curious if there would be an alternative workflow to achieve this for those that don't have an advanced license.

Re: The difference between polygons

JoeBorgione — Wed, 29 Apr 2020 18:00:39 GMT

If you use Union, I think you could tease out those polygons that are not common to both. I don't understand the licensing comment in the help docs that states:

Basic: Limited
Standard: Limited
Advanced: Yes

Re: The difference between polygons

Robert_LeClair — Wed, 29 Apr 2020 18:06:37 GMT

I ran a quick Pro session to see the differences. The first image is the 2 overlapping polygons. The second image is the output from Symmetrical Difference. The third image is the output from Erase. Very different views.

Re: The difference between polygons

MauriceMitchell — Wed, 29 Apr 2020 18:08:41 GMT

Thanks all, I think Erase would be the most useful tool. I will try the others, of course, in order to gain the most knowledge out of the situation.

Re: The difference between polygons

MervynLotter — Wed, 29 Apr 2020 19:42:35 GMT

I think the use of "limited" in the basic and standard license is because you can only Union two files at a time. With the advanced license you can Union a bunch of files at a time.

Re: The difference between polygons

AndresCastillo — Mon, 24 Apr 2023 17:20:44 GMT

If you have two polygons, 'A' and B', run the tabulate intersection tool.

Suppose 'A' has zone fields you want to summarize with.

The result will give you an output table that has the percent of the zone field in A that is covered with B.

you can then join this output table back to the A feature class, keeping all target features, and sort on the joined object id to see all of the records where the joined attributes are null (i.e. null objectid's).

This will tell you with A polygons had 0 coverage from the B polygons.

https://pro.arcgis.com/en/pro-app/latest/tool-reference/analysis/tabulate-intersection.htm

Re: The difference between polygons

AndresCastillo — Mon, 24 Apr 2023 17:21:21 GMT

PostGIS has a similar tool:
https://postgis.net/docs/ST_Difference.html

Re: The difference between polygons

Town_ofCBS_GIS — Thu, 11 Dec 2025 14:10:15 GMT

thank you!! this did exactly what i needed it to.