topic FeatureLayer Calculate SQL Syntax in ArcGIS API for Python Questions

FeatureLayer Calculate SQL Syntax

mapmcburney — Thu, 18 Nov 2021 20:33:45 GMT

Hello I have a Feature Layer with three integer fields (A, B, and C)

I want to calculate the percentage between A and B. The following will run but I only get values of 100 or 0. Nothing in between, and manual calculations prove that there are valid values between 100 and 0.

overlay_result_layer.calculate(where= "1=1",calc_expression={"field": "C", "sqlExpression":"(B/A)*100"})

Can anyone see what is wrong with my syntax?

For additional info, I run the calculation below right before without errors perfectly fine;

overlay_result_layer.calculate(where= "1=1",calc_expression={"field": "B", "sqlExpression": "D * 247.105"})

Re: FeatureLayer Calculate SQL Syntax

jcarlson — Thu, 18 Nov 2021 21:30:41 GMT

It's the integers. Take your first expression, (B/A) * 100. Since B/A evaluates first, you're stuck with whatever rounded integer value results from the division. That is, 0 or 1, which then multiplied by 100 gives you 0 and 100, respectively.

Try instead, (B*100)/A. By multiplying your integer first, you avoid truncating the divided value as drastically.

Re: FeatureLayer Calculate SQL Syntax

mapmcburney — Thu, 18 Nov 2021 21:45:38 GMT

You are a legend! Thank you!