topic Re: Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes in Python Questions

Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes

Anonymous User — Fri, 26 Mar 2021 19:40:37 GMT

FULL DISCLOSURE: New to Python, so using the built in Python code blocks within field calculator would work best for me. 🙂

I'm using a Census tract shapefile with their corresponding attributes of interest within ArcMap 10.7.1. My project goal is to identify the subset of tracts that share a line segment while:

maximizing the sum of unemployed people for all tracts (attribute #1) and
keeping the unemployment rate for all tracts under 6.5 percent (attribute #2, unemployment rate will need to be calculated as the sum of one field divided by the sum of another field for the selected tracts).

In the past, I've used tools to identify polygons that share a border, and I used the 'Select by Attributes' tool in another project to query.

However, I'm stuck because this particular project has an interdependent set of criteria based on both spatial relationship and corresponding attributes.

How to efficiently model multiple iterations to find optimal solution?

Re: Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes

DanPatterson — Fri, 26 Mar 2021 19:40:17 GMT

why is this a python question?

step 2 is a field calculator calculation

your boundary line doesn't appear to have changed so it is still a spatial selection

not sure what you mean by maximizing the number of employed people.

If you can deal with your individual requirements, then an "overlay" of some kind will determine where, and if, the combinations can be met. That would be the starting point for any kind of model, process or script

Re: Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes

Anonymous User — Fri, 26 Mar 2021 19:52:09 GMT

I need to select a set of contiguous tracts where the total number of unemployed people within those tracts (calculated as the sum of attribute #1) is as high as possible while the quotient calculated from 2 other fields remains below "6.5".

Seemed like a Field Calc (python-related) question. Perhaps I posted to the wrong forum.

Not sure what you mean by "sort of retired"

Re: Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes

DanPatterson — Fri, 26 Mar 2021 20:53:51 GMT

Summarize Within (Analysis)—ArcGIS Pro | Documentation will give you the summary of your desired fields (eg total)

or even

Summary Statistics (Analysis)—ArcGIS Pro | Documentation you can get your ratio there and you can select by attributes from it.

"sort of retired" my signature, representing my life status

Re: Find Optimal Subset of Feature Layer Based on Spatial Criteria and Attributes

Anonymous User — Sat, 27 Mar 2021 02:22:04 GMT

I wish I was "sort of retired " lol. Thanks @DanPatterson