Arcade: How to Symbolize a Feature Layer by Submission Frequency Using Arcade in ArcGIS Online?

[GrishaPost]

Hello,

I have a polygon feature layer created from a Survey123 form where the geometry comes from a list of counties in South Carolina. My goal is to symbolize the county's feature layer by the number of times in the survey that people submit that county:

• Green, if nobody submits a county (count = 0)
• Yellow, if the count of that county is between 1 and 5 (count between 1 and 5)
• Orange (count greater than 5)

I tried to use Arcade, but wasn’t successful. I was able to do this using a Python Notebook, but I am concerned about the credit usage. Is there a function/expression in Arcade that I am missing that will help me achieve this?

Thank you for your help.

Grisha.

[DavidPike · Accepted solution]

I'd probably do this at the feature layer level.  Have a polygon feature layer with the County geometries and name.

Then create a feature layer join view https://doc.arcgis.com/en/arcgis-online/manage-data/create-hosted-views.htm using the county name to match against.

Your resulting view will have a join_count field to then symbolise by.

[GrishaPost]

Thank you so much for your response! I believe I did a similar process with my Python script, except I didn't create a feature layer join view. I will explore this! Please find my Python script below.

https://github.com/ClemsonGIS/Fall_ArmyWorm_Survey_Count

My current Survey has a location list question tied to a polygon feature layer of counties in South Carolina.  The count of the records per county is visible when the county field "Information" button is selected within the feature layer attribute table.

I was wondering if it is possible to symbolize the count per county in the polygon feature layer without using another layer, because the count is already being calculated as a summary statistic behind the scenes?

[GrishaPost]

I just tested the feature layer join view, and it works wonderfully. Thank you!

Best,

Grisha

[RussRoberts]

Did you consider using data pipelines to run on a schedule to update the field to change the counts?  We don't support using featuresets to handle rendering between two layers because this would require that expression to run on every map interaction to run the expression. 

[GrishaPost]

Thank you so much, Russ! I have not explored data pipelines, but will look into using them. I was wondering if it would be possible to symbolize counts by just using one feature layer (the feature layer created from the survey)

My current Survey has a location list question tied to a polygon feature layer of counties in South Carolina. 

The count of the records per county is visible when the county field "Information" button is selected within the feature layer attribute table (please see screenshot below).

I was wondering if it is possible to symbolize the count per county in the polygon feature layer without using another layer, because the count is already being calculated as a summary statistic behind the scenes?

[RPGIS]

In ArcGIS Dashboards this is a capability and it might be a capability in the map viewer symbology but I'll need to run a few tests to see what expression can make it possible. 

[RPGIS]

I ran some tests and @DavidPike is correct if you want to symbolize based on another polygon attribute from a survey. Once the join view is created then I believe you can symbolize the feature layers, using arcade, that differentiate based on count.

The only other option that I see is if you configure your survey to populate a field and have an arcade expression calculate that field based on another layer. You can then use arcade to symbolize the colors based on the counts of that field.

[patriciacdale]

I am not sure why the need to join to another layer when the Count is intrinsic to the dataset as shown in the screenshot provided by Grisha. It seems this should be easily handled by Arcade since it's already creating the statistic behind the scenes (Count). 

[RPGIS]

You would be correct if the survey itself calculates based on another layer. Since the OP is looking to find which polygons intersect the survey points then @DavidPike is correct. If, however, the survey were set to get a calculation everytime a survey is submitted then arcade would work.