With the following, I am trying to select each polygon by its name, select points from another feature class that are within the selected polygon, then calculate a field using the same name that was used to select the polygon (by attributes). A spatial intersect, or any other method that results in creating a new FC as output and having to do joins won't work here, as this is (hopefully) to be an unattended nightly update script. It iterates through the polygons fine, but the result is that ALL points get the name of the last polygon. import os import errno import arcpy import sys import traceback from arcpy import env update_feature_class = r 'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\GRSM_RESEARCH_LOCATIONS' county_feature_class = r 'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\CountyBoundaries' with arcpy . da . SearchCursor ( county_feature_class , [ 'SHAPE@' , 'NAME' ] ) as cursor : for row in cursor : print ( 'Selecting ' + row [ 1 ] ) expression = "NAME = '" + row [ 1 ] + "'" arcpy . SelectLayerByAttribute_management ( county_feature_class , "NEW_SELECTION" , expression ) arcpy . SelectLayerByLocation_management ( update_feature_class , "INTERSECT" , county_feature_class ) arcpy . CalculateField_management ( update_feature_class , "COUNTY" , "'" + row [ 1 ] + "'" , "PYTHON3" )

I agree with Dan that either starting a new question or branching this question to another thread would be good given the length and slight topic change. What I will say here, though, is that reading through the script for me is made more difficult by naming rows from the cursors with names like "polygon" and "point." Typically when something is named "polygon," it is a polygon object and not a row containing a polygon object and other attributes. Maybe it is just me, but I catch myself having to go back and remind myself what exactly "polygon" and "point" are when I see polygon[0] because ArcPy polygon objects do support indexing and slicing. Beyond variable naming, I am trying to understand why you are creating a poly_count counter when you can just check the length of the poly_names list to get the count. And I don't see poly_count actually being used anywhere. Since Python dictionaries are not inherently spatial, looping over them and doing spatial operations on each geometry stored within them can be slow depending on how many polygons are being iterated over, but I haven't followed this thread closely until now, so maybe that discussion already happened. If so, disregard this last comment.

centroid within a distance of.... if you are doing some kind of select by attributes (thread is too long and convoluted now)

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Iterate selection and calculate field not working

ThomasColson

With the following, I am trying to select each polygon by its name, select points from another feature class that are within the selected polygon, then calculate a field using the same name that was used to select the polygon (by attributes). A spatial intersect, or any other method that results in creating a new FC as output and having to do joins won't work here, as this is (hopefully) to be an unattended nightly update script. It iterates through the polygons fine, but the result is that ALL points get the name of the last polygon.

<SPAN class="keyword token">import</SPAN> os
<SPAN class="keyword token">import</SPAN> errno
<SPAN class="keyword token">import</SPAN> arcpy
<SPAN class="keyword token">import</SPAN> sys&nbsp; 
<SPAN class="keyword token">import</SPAN> traceback&nbsp; 
<SPAN class="keyword token">from</SPAN> arcpy <SPAN class="keyword token">import</SPAN> env
update_feature_class <SPAN class="operator token">=</SPAN> r<SPAN class="string token">'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\GRSM_RESEARCH_LOCATIONS'</SPAN>
county_feature_class <SPAN class="operator token">=</SPAN> r<SPAN class="string token">'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\CountyBoundaries'</SPAN>

<SPAN class="keyword token">with</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>da<SPAN class="punctuation token">.</SPAN>SearchCursor<SPAN class="punctuation token">(</SPAN>county_feature_class<SPAN class="punctuation token">,</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="string token">'SHAPE@'</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="string token">'NAME'</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">)</SPAN> <SPAN class="keyword token">as</SPAN> cursor<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> row <SPAN class="keyword token">in</SPAN> cursor<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">print</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">'Selecting '</SPAN><SPAN class="operator token">+</SPAN>row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; expression <SPAN class="operator token">=</SPAN> <SPAN class="string token">"NAME = '"</SPAN><SPAN class="operator token">+</SPAN>row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="operator token">+</SPAN><SPAN class="string token">"'"</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>SelectLayerByAttribute_management <SPAN class="punctuation token">(</SPAN>county_feature_class<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NEW_SELECTION"</SPAN><SPAN class="punctuation token">,</SPAN> expression<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>SelectLayerByLocation_management<SPAN class="punctuation token">(</SPAN>update_feature_class<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"INTERSECT"</SPAN><SPAN class="punctuation token">,</SPAN> county_feature_class<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>CalculateField_management<SPAN class="punctuation token">(</SPAN>update_feature_class<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"COUNTY"</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="string token">"'"</SPAN><SPAN class="operator token">+</SPAN>row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="operator token">+</SPAN><SPAN class="string token">"'"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"PYTHON3"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

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ThomasColson

This worked as well, https://community.esri.com/thread/221620-iterate-selection-and-calculate-field-not-working#comment-802163 albeit very fast!

ThomasColson

Hi all, thanks for all the detailed replies. I got sideways with some other more priority mapping requirements last few weeks, I'm skipping cutting firewood today so I can wade through the responses here!

This one worked:

https://community.esri.com/thread/221620-iterate-selection-and-calculate-field-not-working#comment-801415

BenjaminSperry1

Perhaps we are all barking up the wrong tree.

You could just do a spatial join on the new points from that day with a persistent county fc with the output in_memory with just the name field carried over from the county fc.

Then append that to a long term points fc.

You could then programmatically delete all that days features from the new points fc so you are working from an empty data set each day.

Roughly (I'm sure Richard will pick up on any errors):

import arcpy

# Establish parameters
new_features = #  A temporary feature class that is reset each day
county_feature_class = #  The county feature class used to get county names
historical_features = # A feature class you add new points to as they come along


county_points = arcpy.analysis.SpatialJoin(new_features, county_feature_class, "in_memory/County_points",
                                           "JOIN_ONE_TO_MANY", "KEEP_ALL",[fields you want to cary over],
                                           "INTERSECT", None, None)

arcpy.Append_management(county_points, historical_features, "NO_TEST",...)

When I tested is using GP tools within ArcGIS Pro it only took 7 seconds total for all the cities an counties in the US.

DanPatterson_Retired

From https://community.esri.com/thread/221620-iterate-selection-and-calculate-field-not-working#comment-801387

pip_arc

len(pnts)
2000

len(polys)
100

<SPAN class="operator token">%</SPAN>timeit pip_arc<SPAN class="punctuation token">(</SPAN>pnt_fc<SPAN class="punctuation token">,</SPAN> poly_fc<SPAN class="punctuation token">)</SPAN>
<SPAN class="number token">1.44</SPAN> s ± <SPAN class="number token">118</SPAN> ms per loop <SPAN class="punctuation token">(</SPAN>mean ± std<SPAN class="punctuation token">.</SPAN> dev<SPAN class="punctuation token">.</SPAN> of <SPAN class="number token">7</SPAN> runs<SPAN class="punctuation token">,</SPAN> <SPAN class="number token">1</SPAN> loop each<SPAN class="punctuation token">)</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

plus another second or so for ExtendTable

Why are the alternatives taking so long? is it because of where they reside

RichardFairhurst

I would add a break after matching the first County name, since your code only stores one county name and there is no point in continuing to match county names after that. However, I think if you run my code you will find that reseting a cursor for every point is much slower than iterating over a dictionary or list which were loaded into memory by running the County cursor once. I believe the cursor reset is repeatedly accessing data on disk, which will be very time consuming in a process that grows exponentially as each new county or point is added. I would encourage you to try either of my last two code examples on your test data to see for yourself the difference that using in memory data can make. Every optimization in the part of the code that is subject to exponential growth should be considered critical to making a process like this at all scalable.

BenjaminSperry1

Hello Thomas,

Here is a simple script you can work from.

import arcpy

# Establish parameters
city_feature_class = arcpy.GetParameterAsText(0)  # A point fc (string)
county_feature_class = arcpy.GetParameterAsText(1)  # A polygon fc (string)

# Set up search cursor for county fc
with arcpy.da.SearchCursor(county_feature_class, ['SHAPE@', 'NAME']) as search_cursor:
    # Set up update cursor for point fc
    with arcpy.da.UpdateCursor(city_feature_class, ['SHAPE@', 'Test_County']) as cursor:

        # Iterate through counties
        for polygon in search_cursor:
            county = polygon[0]
            name = polygon[1]

            # Iterate through cities
            for row in cursor:
                point = row[0]
                if point.within(county):
                    row[1] = name
                    cursor.updateRow(row)

            cursor.reset()

del search_cursor
del cursor

I tested it by running the code to add county names to every city within the county and then compared it against the county field in the city feature class to make sure it ran correctly.

It is pretty good performance wise, when I ran it against all the cities (1,015) in all the counties (67) in Florida it ran in less than a minute. When I ran all the cities (38,186) in all the counties (3,142) in the entire US it took just under an hour. If you are running it over night it shouldn't be an issue.

Cheers,

Ben

DanPatterson_Retired

This gets more complicated all the time next it will have to be updated on a mobile device

mvolz47

If you use intersect to capture points on the border, wouldn't you then have to deal with 2 names from the 2 polygons that intersect the point that is on the border of each polygon?

RichardFairhurst

Try the code below. It does not alter the schema at all and updates values in an existing field. It is also more efficient than your original approach and will minimize the number of polygon to point comparisons required to match all of the county names to the points.

import arcpy

update_feature_class = r'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\GRSM_RESEARCH_LOCATIONS'
county_feature_class = r'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\CountyBoundaries'

county_count = 0
relateDict = {}
# Set up search cursor for county fc
with arcpy.da.SearchCursor(county_feature_class,['NAME','SHAPE@']) as search_cursor:

&nbsp;&nbsp;&nbsp; # Iterate through counties
&nbsp;&nbsp;&nbsp; for polygon in search_cursor:
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if not polygon[0] in relateDict:
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; relateDict[polygon[0]] = polygon[1]
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; else:
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; relateDict[polygon[0]] = relateDict[polygon[0]].union(polygon[1])

for name in relateDict:
&nbsp;&nbsp;&nbsp; county_count += 1

point_count = 0
comparison_count = 0
# Set up update cursor for point fc
with arcpy.da.UpdateCursor(update_feature_class, ['SHAPE@', 'COUNTY']) as update_cursor:

&nbsp;&nbsp;&nbsp; # Iterate through points
&nbsp;&nbsp;&nbsp; for point in update_cursor:
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; point_count += 1
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; for name in relateDict:
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; comparison_count += 1
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; county = relateDict[name]
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # Check if the current point is within the current polygon
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if point[0].within(county):&nbsp; # Returns True or False
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # Set the value of the field as the county name
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; point[1] = name
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # Update the cursor with the new value
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; update_cursor.updateRow(point)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; break
print("Processed {0} County/Point comparisons for {1} Counties and {2} Points".format(comparison_count, county_count, point_count))
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ThomasColson

I think an example like that would have pretty broad application beyond my use. Lots of folks needing to make spatial type updates to feature services that are driving feature services, e.g a field survey of stormwater drains using collector and the python updates what zoning district or whatever, without requiring alterations to the schema or service disruption.

DanPatterson_Retired

I can fix that, extendtable is like a join, but permanent, you have a common id field, then you can join anything, string, integer float, a single field or multiple fields

I use it all the time, with or without field deletion.

But it sounds like you aren't doing this stuff when the data can be worked with or it wouldn't have locks

I will post a blog, scripts and a toolbox so you can read it at your leisure

ThomasColson

Dan, it's been a few days and things are going sideways at work but: I got your code to run, but the problem(s) I'm running into are twofold: I need a string (county name) to be added to an existing string field in the points layer. The numpy solution seems to be limited to only adding an integer to a new field. I was reading the numpy documentation and fiddling around with string arrays, and getting nothing done other than throw errors. Another limitation here is temporarily adding fields, doing joins, etc...as these feature classes are pushing feature services, which put a schema lock on the feature classes, so adding fields is not possible.

DanPatterson_Retired

Thomas... still ruled out ExtendTable with a Delete field, if needed, as an option? It certainly gets around that cursor stuff and could be added to to check for bad geometries if needed

RichardFairhurst

You original code fails because you have not created layers for the two feature classes and are using the feature classes directly. I am surprised the select actions did not cause an error, because they only work with layers, not feature classes. The Calculate Field will always calculate every record if the input is a feature class and not a layer.

Your code would work if you create layers from the feature classes and use the layers:

<SPAN class="keyword token">import</SPAN> arcpy
update_feature_class <SPAN class="operator token">=</SPAN> r<SPAN class="string token">'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\GRSM_RESEARCH_LOCATIONS'</SPAN>
county_feature_class <SPAN class="operator token">=</SPAN> r<SPAN class="string token">'C:\Users\tcolson\Documents\ArcGIS\Projects\MyProject\MyProject.gdb\CountyBoundaries'</SPAN>

arcpy<SPAN class="punctuation token">.</SPAN>MakeFeatureLayer_management<SPAN class="punctuation token">(</SPAN>update_feature_class<SPAN class="punctuation token">,</SPAN><SPAN class="string token">"update_lyr"</SPAN><SPAN class="punctuation token">)</SPAN>
arcpy<SPAN class="punctuation token">.</SPAN>MakeFeatureLayer_management<SPAN class="punctuation token">(</SPAN>county_feature_class<SPAN class="punctuation token">,</SPAN><SPAN class="string token">"county_lyr"</SPAN><SPAN class="punctuation token">)</SPAN>
<SPAN class="keyword token">with</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>da<SPAN class="punctuation token">.</SPAN>SearchCursor<SPAN class="punctuation token">(</SPAN>county_feature_class<SPAN class="punctuation token">,</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="string token">'NAME'</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">)</SPAN> <SPAN class="keyword token">as</SPAN> cursor<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> row <SPAN class="keyword token">in</SPAN> cursor<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; county_name <SPAN class="operator token">=</SPAN> row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">print</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">'Selecting '</SPAN><SPAN class="operator token">+</SPAN>county_name<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; expression <SPAN class="operator token">=</SPAN> <SPAN class="string token">"NAME = '"</SPAN><SPAN class="operator token">+</SPAN>county_name<SPAN class="operator token">+</SPAN><SPAN class="string token">"'"</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>SelectLayerByAttribute_management <SPAN class="punctuation token">(</SPAN><SPAN class="string token">"county_lyr"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NEW_SELECTION"</SPAN><SPAN class="punctuation token">,</SPAN> expression<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>SelectLayerByLocation_management<SPAN class="punctuation token">(</SPAN><SPAN class="string token">"update_lyr"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"INTERSECT"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"county_lyr"</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>CalculateField_management<SPAN class="punctuation token">(</SPAN><SPAN class="string token">"update_lyr"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"COUNTY"</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="string token">"'"</SPAN><SPAN class="operator token">+</SPAN>county_name<SPAN class="operator token">+</SPAN><SPAN class="string token">"'"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"PYTHON3"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

ThomasColson

yeah, checked that. 700+ points, each one of them is constrained by a polyogn (7 of them). Data is local FGDB created by Pro

DanPatterson_Retired

null point? or not a point featureclass? it is a point in polygon demo, assume your are working local, adjust if otherwise

JoshuaBixby

A spatial intersect, or any other method that results in creating a new FC as output and having to do joins won't work here, as this is (hopefully) to be an unattended nightly update script.

As much as I like ArcPy, there are times using geoprocessing tools are both the fastest and best way to get a task done. What it is about this being an unattended nightly update script that you think disallows the use of geoprocessing tools that results in new feature classes?

ThomasColson

Traceback (most recent call last):
File "C:\Users\bigfoot\Documents\ArcGIS\Projects\MyProject\PIP_TEST.py", line 33, in <module>
out = pip_arc(pnt_fc, poly_fc) # ---- run pip_arc and convert to array
File "C:\Users\bigfoot\Documents\ArcGIS\Projects\MyProject\PIP_TEST.py", line 23, in pip_arc
if p.within(pol):
AttributeError: 'NoneType' object has no attribute 'within'

Both FC"s are GCS NAD 83

DanPatterson_Retired

<SPAN class="keyword token">import</SPAN> numpy <SPAN class="keyword token">as</SPAN> np
<SPAN class="keyword token">import</SPAN> arcpy

<SPAN class="keyword token">def</SPAN> <SPAN class="token function">id_geom</SPAN><SPAN class="punctuation token">(</SPAN>in_fc<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""The main code segment which gets the id and shape information and
&nbsp;&nbsp;&nbsp; explodes the geometry to individual points
&nbsp;&nbsp;&nbsp; """</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">with</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>da<SPAN class="punctuation token">.</SPAN>SearchCursor<SPAN class="punctuation token">(</SPAN>in_fc<SPAN class="punctuation token">,</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="string token">'OBJECTID'</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">'SHAPE@'</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">)</SPAN> <SPAN class="keyword token">as</SPAN> cursor<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; a <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">[</SPAN>row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">,</SPAN> row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">]</SPAN> <SPAN class="keyword token">for</SPAN> row <SPAN class="keyword token">in</SPAN> cursor<SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> a


<SPAN class="keyword token">def</SPAN> <SPAN class="token function">pip_arc</SPAN><SPAN class="punctuation token">(</SPAN>pnt_fc<SPAN class="punctuation token">,</SPAN> poly_fc<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Naive point-in-polygon using arcpy
&nbsp;&nbsp;&nbsp; """</SPAN>
&nbsp;&nbsp;&nbsp; pnts <SPAN class="operator token">=</SPAN> id_geom<SPAN class="punctuation token">(</SPAN>pnt_fc<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp; polys <SPAN class="operator token">=</SPAN> id_geom<SPAN class="punctuation token">(</SPAN>poly_fc<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp; out <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> pnt <SPAN class="keyword token">in</SPAN> pnts<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pid<SPAN class="punctuation token">,</SPAN> p <SPAN class="operator token">=</SPAN> pnt
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> poly <SPAN class="keyword token">in</SPAN> polys<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; plid<SPAN class="punctuation token">,</SPAN> pol <SPAN class="operator token">=</SPAN> poly
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">if</SPAN> p<SPAN class="punctuation token">.</SPAN>within<SPAN class="punctuation token">(</SPAN>pol<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; out<SPAN class="punctuation token">.</SPAN>append<SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">[</SPAN>pid<SPAN class="punctuation token">,</SPAN> plid<SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">)</SPAN>&nbsp; <SPAN class="comment token">#[pid, p, plid, pol])</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">break</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">continue</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> out

<SPAN class="comment token"># ----</SPAN>
pnt_fc <SPAN class="operator token">=</SPAN> r<SPAN class="string token">"path_to\your.gdb\pnts_2000"</SPAN>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># points featureclass</SPAN>
poly_fc <SPAN class="operator token">=</SPAN> <SPAN class="string token">"path_to\your.gdb\SamplingGrids"</SPAN>&nbsp; <SPAN class="comment token"># polygon featureclass</SPAN>

out <SPAN class="operator token">=</SPAN> pip_arc<SPAN class="punctuation token">(</SPAN>pnt_fc<SPAN class="punctuation token">,</SPAN> poly_fc<SPAN class="punctuation token">)</SPAN>&nbsp; <SPAN class="comment token"># ---- run pip_arc and convert to array</SPAN>
out <SPAN class="operator token">=</SPAN> np<SPAN class="punctuation token">.</SPAN>array<SPAN class="punctuation token">(</SPAN>out<SPAN class="punctuation token">)</SPAN>
dt <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">'PntID'</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">'<i4'</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="punctuation token">(</SPAN><SPAN class="string token">'PolyID'</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">'<i4'</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">]</SPAN>&nbsp; <SPAN class="comment token"># ---- make an output array</SPAN>
z <SPAN class="operator token">=</SPAN> np<SPAN class="punctuation token">.</SPAN>ndarray<SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">(</SPAN>len<SPAN class="punctuation token">(</SPAN>out<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">,</SPAN> dtype<SPAN class="operator token">=</SPAN>dt<SPAN class="punctuation token">)</SPAN>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># to be used with ExtendTable</SPAN>
z<SPAN class="punctuation token">[</SPAN><SPAN class="string token">'PntID'</SPAN><SPAN class="punctuation token">]</SPAN> <SPAN class="operator token">=</SPAN> out<SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">:</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN> 
z<SPAN class="punctuation token">[</SPAN><SPAN class="string token">'PolyID'</SPAN><SPAN class="punctuation token">]</SPAN> <SPAN class="operator token">=</SPAN> out<SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">:</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN>

arcpy<SPAN class="punctuation token">.</SPAN>da<SPAN class="punctuation token">.</SPAN>ExtendTable<SPAN class="punctuation token">(</SPAN>pnt_fc<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"OBJECTID"</SPAN><SPAN class="punctuation token">,</SPAN> z<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"PntID"</SPAN><SPAN class="punctuation token">)</SPAN>&nbsp; <SPAN class="comment token"># --- make sure Pro is closed‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

DanPatterson_Retired

It is not a select by attribute loop. You have your points and your polygons. You loop through the points and when it is found in a polygon you 'pop' it out, grab the polygon id and move on to the next polygon

ThomasColson

No, it doesn't work, it calculates all points, regardless of selection, to the the last "Name" in the loop. How would

contains (second_geometry, {relation}) work any different? You still have to iterate through a select-by-attribute loop?

DanPatterson_Retired

Does it work? You indentation is off, or that is a copy-paste-format problem.

or are you looking for alternatives

If you don't want to use the existing arctoolbox tools, you could do it with the polygon geometry class's

'contains' method

Polygon—ArcPy classes | ArcGIS Desktop

it returns a boolean, so if the feature is within the bounds, you can assign the ID to the feature, then move on to the next polygon

Indicates if the base geometry contains the comparison geometry. contains is the opposite of within.

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