Arcade Intersect Returns Null Field Values

MulfordnSons

I have two layers: A layer of all tax parcels, and a layer of a subset of all the tax parcels. 

I am trying to use Intersect in arcade to return a featureSet that I can then use to inject a field from the subset layer in the pop-up of the layer with all the tax parcels. However, it is returning Null field values, even though there are geometries that clearly overlap (as they are identical). Please see below:

var parcel = Intersects(FeatureSetByName($map,"Name of layer with subset of all tax parcels"), $feature);

for (var f in parcel){
return f.NameOfField
}

 

returns empty result (shown in attached photo).

 

Any obvious reason someone can see this is happening?

emptyIntersect.JPG

alena.jpg

JohannesLindner

When you test your Arcade expression, it only checks one feature (I think it's the first). So if that feature doesn't intersect a feature of your filtered layer, you will get an empty intersect feature set. Your loop will run 0 times and then the expression will return null. If you call First() on an empty feature set, the result is null, which is why you get the ExecutionError when you try to return null.Field

Something like this should do the trick:

var filtered_parcels = Intersects(FeatureSetByName($map,"Name of layer with subset of all tax parcels"), $feature);

var parcel = First(filtered_parcels) // get the first feature

// if filtered_parcels is empty, parcel is null
// in that case, return a default value
if(parcel == null) {
    return "No intersecting subset parcel found."
}
// else return the field value
return parcel.NameOfField

 

When you test that expression, it should show the default result. When you actually open a popup, it should show either the default result or the field of the subset layer, depending on whether there is a subset parcel intersecting the queried feature.