Using Arcade to label polylines with X coordinates of last vertices in ArcGIS Pro

Question

I am using ArcGIS Pro 3.0.0 and a File Geodatabase.

I have a requirement to use Arcade for configuring some Attribute Rules related to the geometry of the features involved which has led me to realize that I am an Arcade beginner. As a learning exercise I am trying to use Arcade for labeling a polyline using the X coordinate of its last vertex without running Calculate Geometry Attributes to add a field first.

I have learned that I can label a polyline with the X coordinate of its first vertex using this Arcade expression:

var first_vertex = Geometry($feature).paths[0][0];
return Text(first_vertex.X);

but how do I label it using the X coordinate of its last vertex?

Answer 1

The clue to doing this came from Calculate coordinates of Polyline in ArcGIS online with Arcade which I adapted for ArcGIS Pro to write this Arcade code which appears to do what I want:

var path_count = Count(Geometry($feature).paths);
var last_vertex = Geometry($feature).paths[0][path_count-1];
return Text(last_vertex.X);

To get the last vertex I needed to count the number of vertices in the polyline (mine was single part) and subtract 1 from it to use as the index value.