topic Re: StopIteration: iteration not started (Python 2.7) in Python Questions

StopIteration: iteration not started (Python 2.7)

NinaBaksh — Mon, 23 Jan 2023 16:44:08 GMT

I need to add about 500 values (street names) to a domain called streetxx. The street names are in a csv file called streetname.csv. I'm using AarcMap 10.8.2. My code is very simple yet I'm getting a StopIteration error. What am I doing wrong? Thanks for the help in advance.

import arcpy
import csv

# Set the path to the CSV file and the geodatabase
csv_file = r"J:\OMS_Upgrade\Water\streetname.csv"
gdb = r"J:\OMS_Upgrade\OMSTest.mdb"

# Set the name of the feature class and field to be updated
fc = "Water_Mains"
field = "Streetxx"

# Use the arcpy.da.UpdateCursor() method to update the feature class
with arcpy.da.UpdateCursor(gdb + "\\" + fc, [field]) as cursor:
# Open the CSV file and read the values
with open(csv_file, "r") as f:
reader = csv.reader(f)
# Skip the header row
next(reader)
# Iterate over the rows in the CSV file
for row in reader:
# Update the field with the value from the CSV file
cursor.updateRow([row[0]])

Here is the error message:

Traceback (most recent call last):
File "J:\OMS_Upgrade\Scripts\Update_Domain.py", line 23, in <module>
cursor.updateRow([row[0]])
StopIteration: iteration not started

Re: StopIteration: iteration not started (Python 2.7)

JohannesLindner — Mon, 23 Jan 2023 16:55:11 GMT

You iterate over the csv file, but arcpy expects you to iterate over the UpdateCursor.

Are you sure UpdateCursor is what you need? It seems like you could actually want InsertCursor.

Re: StopIteration: iteration not started (Python 2.7)

NinaBaksh — Mon, 23 Jan 2023 17:45:20 GMT

Johannes, my day is now improving. Thank you for helping me with this.

I replaced UpdateCursor with InsertCursor and there is no longer an error.

However, the Coded Values did not get updated. I've attached an image of 3 coded values I entered manually beside my list my streetname.csv

Am I missing a step?

Thanks,

Nina

Re: StopIteration: iteration not started (Python 2.7)

JohannesLindner — Mon, 23 Jan 2023 18:23:27 GMT

Ah, I somehow missed the part where you say that you want to update the domain.

In ArcGIS, domains are handled differently from tables. Notably here, the arcpy.da.*Cursor classes only work on tables/feature classes, not on domains. To work with domains, you need the tools from the Data management/Domains toolset.

Something like this should work:

import arcpy import csv # set the variables csv_path = r"G:\ArcGIS\data\streetname.csv" gdb = r"G:\ArcGIS\projects\Test\Test.gdb" domain_name = "TestDomain" # start the csv reader and skip header with open(csv_path, "r") as csv_file: reader = csv.reader(csv_file) next(reader) # loop over the csv rows and write the values into the domain for code, description in reader: arcpy.management.AddCodedValueToDomain(gdb, domain_name, code, description)

Re: StopIteration: iteration not started (Python 2.7)

NinaBaksh — Mon, 23 Jan 2023 21:54:14 GMT

I can't thank you enough Johannes. The above solution works great!