topic Re: Using calculate field to sum values based on two columns, number and string in Python Questions

Using calculate field to sum values based on two columns, number and string

MarilynLong1 — Wed, 31 Mar 2021 21:37:58 GMT

Hi,

I'm trying to use calculate field to add values to my column called Trail Length. I want to populate this column by adding together the trail sections that are part of the same trail.

Example:

Trail Section Length Trail Length

Trail A .5 (script that will add up the values in section length for Trail A, etc)

Trail A .2

Trail B 5

Trail B .3

Trail B 1

Re: Using calculate field to sum values based on two columns, number and string

DanPatterson — Wed, 31 Mar 2021 21:40:07 GMT

Summary Statistics (Analysis)—ArcGIS Pro | Documentation does it for you. See the code sample to call it

Re: Using calculate field to sum values based on two columns, number and string

MarilynLong1 — Wed, 10 Nov 2021 18:53:56 GMT

I've used summary stats to do this in the past but how do I incorporate that into the Field Calculator? I've been trying with Python and Arcade but don't know much about scripting and can't get it to work. This is what I have with Arcade:

GroupBy($layer, 'name', { name: 'trail_ft', expression: 'sec_length_ft', statistic: 'SUM'})

'name' is the column with the names of the trails. 'sec_length_ft' is the name of the column with the length of the sections that make up the trail. 'trail_ft' is the name of the column that I want to be updated.