topic Exclude null symbology from labelling with label expressions in ArcGIS Pro Questions

Exclude null symbology from labelling with label expressions

NormanCone — Thu, 01 May 2025 16:27:21 GMT

I'm working on creating a map and I only need to display the labels for the polygons that have symbology. There are other polygons that are not relevant to this project so I removed their symbology so they aren't displayed. I also want to remove the unit number labels for the polygons that are not represented.

I feel that this would be a fairly easy expression to make in the label properties expression, but I don't have a background in python or arcade. I thought the conditional if-else statement could work, but I couldn't figure it out.

Any help would be appreciated. I would like to learn more about python and arcade coding in Arcgis pro.

Thanks,

Re: Exclude null symbology from labelling with label expressions

ZachBodenner — Thu, 01 May 2025 16:50:17 GMT

How exactly do you determine if the polygon is irrelevant and therefore removed? Is it if the prescription field is anything other than "Old Growth..." or "Shaded Fuel..." ?

In Pro, you can use a command Create Label Classes from Symbology:

This will automatically create SQL queries that match your symbology if you're using Unique Values.

Re: Exclude null symbology from labelling with label expressions

BrendanNewell — Fri, 02 May 2025 01:36:49 GMT

hi @NormanCone, a alterative workflow here is too look at creating a subset of your data with definition queries or selection layers. As both these tools will created new layers that only show the features of interest and will provide a much more simple and robust workflow.

Filter features with definition queries https://pro.arcgis.com/en/pro-app/latest/help/mapping/layer-properties/definition-query.htm
Selection layers - https://pro.arcgis.com/en/pro-app/latest/help/mapping/layer-properties/selection-layers.htm

Re: Exclude null symbology from labelling with label expressions

NormanCone — Mon, 05 May 2025 16:48:51 GMT

Thank you Zach. Using the create label classes from symbology to create distinct labels for each treatment works perfectly. I am creating a map for my marking crew, and this will let me clean-up my may by removing those unnecessary labels. The other symbol class is mastication, and those units don't have to be marked so I don't need to include it in my map. Those polygons will be addressed in a separate contract, but I didn't want to create a separate polygon layer because things can get disorganized quickly.

@BrendanNewell The definition queries tool is very useful and I could consider it here, but for a small data set like this one it's not necessary. I appreciate your tips.