topic Re: TypeError in UpdateCursor query in Python Questions

TypeError in UpdateCursor query

SaraJK — Sat, 11 Dec 2021 08:56:57 GMT

The script I am writing is simply to query multiple fields based on certain criteria and then assign a value to another field. I have multiple queries that need to be built. This is just the beginning as I am stepping into it slowly. This is literally the first script I've tried to write. I started working in Pro 2.4 which is where I am getting the TypeError. I tried it in ArcMap 10.5.1 and it ran fine. After researching a bit, I think it has something to do with changes between Python 2 and 3 but I am not sure. Field 0 is a short data type, Field 1 is a long data type and Field 2 is text.

If anyone has a suggestion on how to make it work in Pro, I would appreciate it.

fc = r"K:\PHYS\PROJECTS\LTSTest.gdb\Streets"
fields = ['LOCAL_SPEED_MPH', 'AADT_NBR', 'TestLTS']
with arcpy.da.UpdateCursor(fc,fields) as cursor:
    for row in cursor:
        if (row[0] <= 25 or row[1] <= 1500):
            row[2] = 1
        elif (row [0] > 40):
            row[2] = 2
        cursor.updateRow(row)
    print("Done")
# Traceback (most recent call last):
#   File "<string>", line 3, in <module>
# TypeError: '<=' not supported between instances of 'NoneType' and 'int'

Re: TypeError in UpdateCursor query

DanPatterson_Retired — Sat, 11 Dec 2021 08:57:00 GMT

You hit a null value in your table, you have to skip those records

for row in cursor:
    if row[0] is Null:
        continue
    if (row[0] <= 25 or row[1] <= 1500):

/blogs/dan_patterson/2016/08/14/script-formatting will help with formatting and line numbers

Re: TypeError in UpdateCursor query

SaraJK — Fri, 14 Feb 2020 20:13:35 GMT

Thanks for the quick reply and formatting help (I couldn't figure out how to do it in the first post).

I added the code you suggested but it came back as "NameError: name 'Null' is not defined" so I changed it to None which seemed to go through. Now, it's back to the same error as before.

Re: TypeError in UpdateCursor query

DanPatterson_Retired — Fri, 14 Feb 2020 21:32:17 GMT

Sorry, it should have been None..

So that suggests that there is None in your other field so try

if row[0] is None or row[1] is None:

if None in row: # think this should work,

In fact, just open the table and query your field for <null> (aka, None), to see what you are dealing with

Re: TypeError in UpdateCursor query

SaraJK — Tue, 18 Feb 2020 19:58:45 GMT

Had to think a little bit (I'm taking baby steps with this...) but yes, it did work once I realized I needed to use row[1] instead of 0 because that is where some null values are. Thanks again for the help.