topic Arcade data expression resulting in Nan when summed in ArcGIS Online Questions

Arcade data expression resulting in Nan when summed

Hayley — Mon, 05 Dec 2022 03:49:47 GMT

I am trying to return the sum of integer fields in a layer, however, am getting a NaN result. I have tried with Count and the correct number appears, so why does Sum not work? What am I missing here?

I am using this in a data expression to use in Dashboards list widget. Any pointers are greatly appreciated!!

var features = FeatureSetByPortalItem( Portal('https://adcgis.maps.arcgis.com'), '91feaa24f7d34f9299f5b99cbd7328ed', 1, ["C18_Indst_URAdr_AgriForestFish"], false ); Sum(features);

Result Value Result NaN Type Number

Re: Arcade data expression resulting in Nan when summed

jcarlson — Mon, 05 Dec 2022 15:05:54 GMT

When you use the Sum function with a single parameter, it expects an array of summable values.

When you're using a FeatureSet, you need to supply a second parameter with the field name you want summed, as there could be any number of fields in a FeatureSet. Even when you only specify a single field, it will likely still have an ObjectID field, so it needs to be told which field you want.

Try Sum(features, 'C18_Indst_URAdr_AgriForestFish')

Re: Arcade data expression resulting in Nan when summed

Hayley — Mon, 05 Dec 2022 19:35:01 GMT

Hi @jcarlson, thanks for explaining!

The expression now results in the correct number:

var features = FeatureSetByPortalItem( Portal('https://adcgis.maps.arcgis.com'), '91feaa24f7d34f9299f5b99cbd7328ed', 1, ["C18_Indst_URAdr_AgriForestFish"], false ); return(Sum(features, 'C18_Indst_URAdr_AgriForestFish'))

However in dashboards it says the Arcade expression is unable to be executed? How do I enable it to be used in my widgets?

Re: Arcade data expression resulting in Nan when summed

jcarlson — Mon, 05 Dec 2022 20:11:46 GMT

Oh, I'm sorry! I thought this was an Advanced Formatting thing, I missed the part about it being a Data Expression. A Data Expression needs a FeatureSet as its output.

You could write this up as a Data Expression easily enough, but can I ask how you're using the data in your dashboard? If all you need is the number, you could get that into something like an Indicator widget without needing a separate expression.

In any case, the easiest way to get an output FeatureSet is to use GroupBy, which can handle the aggregation for you, too.