topic Python script question in ArcGIS Pro Questions

Python script question

JRR — Wed, 23 Oct 2024 18:27:37 GMT

UseThis = 2
##
arcpy.SelectLayerByLocation_management("BIRDLINE_LAYER", "intersect", "BigPoly", 0, "new_selection")
arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', '"Route" = 2')
#arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', '"Route" = UseThis')
#arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', "UseThis" )

Only the first 'SUBSET_SELECTION', works. How can I use the value of 'UseThis' ??

Re: Python script question

CodyPatterson — Wed, 23 Oct 2024 19:09:43 GMT

Hey @JRR

I think you need to pass the input as a function string:

UseThis = 2 arcpy.SelectLayerByLocation_management("BIRDLINE_LAYER", "intersect", "BigPoly", 0, "new_selection") arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', '"Route" = 2') arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', f'"Route" = {UseThis}')

Cody

Re: Python script question

JRR — Wed, 23 Oct 2024 19:36:19 GMT

That seems to only apply to rasters. Thanks for your response!

arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', f'"Route" = {UseThis}')

show invalid expression

Re: Python script question

CodyPatterson — Wed, 23 Oct 2024 19:57:39 GMT

Hey @JRR

Ah alright I see, it may be because your Route attribute is expected to be a certain data type, if it's an integer it would be something like this:

arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', f'"Route" = {UseThis}')

Otherwise, if it is a string, it should be this here:

arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', f'"Route" = \'{UseThis}\'')

This escapes the single quotes to be used in the SQL. Hopefully this solves it for you!

Cody

Re: Python script question

JRR — Thu, 24 Oct 2024 21:21:24 GMT

Neither of these lines work.

Re: Python script question

CodyPatterson — Fri, 25 Oct 2024 13:37:36 GMT

Hey @JRR

The errors are not very descriptive using IDLE, you may have better luck and better error reporting when using Visual Studio Code instead.

Give this a shot here, this builds the query outside of the function:

UseThis = 2 arcpy.SelectLayerByLocation_management("BIRDLINE_LAYER", "intersect", "BigPoly", 0, "new_selection") sql_expression = f'"Route" = {UseThis}' print(sql_expression) # Just use this to test to see if it's actually printing anything and that the expression looks correct arcpy.SelectLayerByAttribute_management('BIRDLINE_LAYER', 'SUBSET_SELECTION', sql_expression)

I would ensure that the print statement is in there for debugging.

Cody

Re: Python script question

JRR — Fri, 01 Nov 2024 18:28:17 GMT

I tried with no success. Sorry to be so late in responding.. traveling.

Sent the code and a sample data set.