ArcGIS Pro 3.1.2 - How to create variable with all features in Arcade?

Question

Hi,

I have an Arcade expression in which I would like to look through all features for calculation.

I start my expression as:

var Zoning = FeatureSetByName($layer,["City"],true);

I would like to use the variable 'Zoning' to loop in order to calculate in each $feature using the 'City' attribute and the geometry (hence 'True')

In Arcade, I though I could simply point to the current layer using $layer but it does not work!

For info, I am using this Arcade expression in Calculate Field in Model Builder and I cannot easily reference the $datastore name as it is dynamic.

Any help  appreciated

VincentLaunstorfer · Answer

I think I found out the reason why global variable $layer gives an Object not found error.

In Field Calculation profile, only $feature and $datastore can be used in Aracde. Not $layer.

https://developers.arcgis.com/arcade/profiles/field-calculation/

As I use this this Arcade expression in Field Calculation in ModelBuilder with a dynamic feature class name, I have no chance to re-use the ModelBuilder variable pointing to my feature class in the Arcade script...

Never mind, I will perform my calculation differently.

VincentLaunstorfer · Answer

Hi,

Finally, I am trying to use the $layer global variable to loop through all features in order to sum acreage per cities. The Arcade expression makes an initial distinct list of cities in the $layer and then calculates acreage acreage accordingly for each $feature, as follow:

var myArray = [];
var i = 0;
for(var z in $layer) {
    Insert(myArray, i, z.City);
    i = i + 1;
}

var myArrayDistinct = Distinct(myArray);
var myArrayDistinctSort = Sort(myArrayDistinct);

var acreage = 0;

for(var a in myArrayDistinctSort) {
    for(var z in $layer) {
        if (z.City == myArrayDistinctSort[a]) {
            acreage = acreage + z.AreaGeodetic(z, 'acres');
        }
    }
}
return acreage;

but I still get an:

Invalid expression.
Error on line 3.
Object not found $layer

For info, I am using this Arcade expression in Calculate field tool.

Any guess?

VincentLaunstorfer · Answer

Fantastic!

I will try that. I knew there was something easy.

Appreciated