SelectLayerByLocation blowing out

JeffHanson2

I'm trying to take a point in a search cursor and then find what section it is in.   I have a bioFC and a "sec_lyr" and I am passing in the feature from the cursor - looping through the cursor.   It is not working.   How can I iterate one point feature at a time?

 

    cursor = arcpy.da.SearchCursor(bioFC, ["Twp_Sec_Rng"])

    arcpy.MakeFeatureLayer_management(secFC, "sec_lyr")

    # loop one, is a search cursor

    print("Processing data...")

    for fea in cursor:

        arcpy.SelectLayerByLocation_management("sec_lyr", "intersect", fea)

Hayden Welch

If you're trying to make a selection in a map the other advice is good. If you want to update the underlying data with Cursors, you'd do it like this:

 

import arcpy   

secFC = "<path>"
bioFC = "<path>"
bioDesc = arcpy.Describe(bioFC)

# Get BIO FC fields
bioFields = [f.name for f in bioDesc.fields]

# Add Twp_Sec_Rng field if not present
if 'Twp_Sec_Rng' not in bioFields:
    arcpy.AddField_management(bioFC, "Twp_Sec_Rng", "TEXT", field_length=255)

print("Processing data...")

# Create a dictionary of sections with their polygons
secs: dict[str,arcpy.Polygon] =\
    {
        row[1]: row[0]
        for row in arcpy.da.SearchCursor(secFC, ["SHAPE@", "Twp_Sec_Rng"])
    }

# Iterate Sections
for sec_id, sec_shape in secs.items():
    
    # Use spatial filter to update only the rows within the section
    with arcpy.da.UpdateCursor(bioFC, ["Twp_Sec_Rng"], spatial_filter=sec_shape, spatial_relationship="INTERSECTS") as cursor:
        for row in cursor:
            row[0] = sec_id
            cursor.updateRow(row)

Also if your section table is really big and can't fit in memory, you can modify that initial secs dictionary to be a generator:

 

import arcpy   
from typing import Generator

secFC = "<path>"
bioFC = "<path>"
bioDesc = arcpy.Describe(bioFC)

# Get BIO FC fields
bioFields = [f.name for f in bioDesc.fields]

# Add Twp_Sec_Rng field if not present
if 'Twp_Sec_Rng' not in bioFields:
    arcpy.AddField_management(bioFC, "Twp_Sec_Rng", "TEXT", field_length=255)

print("Processing data...")

# Create a Generator for Sections. This is more memory efficient if the number of sections is very large.
secs: Generator[tuple[str,arcpy.Polygon], None, None] =\
    (
        (row[1], row[0])
        for row in arcpy.da.SearchCursor(secFC, ["SHAPE@", "Twp_Sec_Rng"])
    )

# Iterate Sections
for sec_id, sec_shape in secs:
    
    # Use spatial filter to update only the rows within the section
    with arcpy.da.UpdateCursor(bioFC, ["Twp_Sec_Rng"], spatial_filter=sec_shape, spatial_relationship="INTERSECTS") as cursor:
        for row in cursor:
            row[0] = sec_id
            cursor.updateRow(row)