topic Re: KeyError when working with fields in Python Questions

KeyError when working with fields

VishalShah2 — Fri, 10 Dec 2021 22:31:13 GMT

I get KeyError: 5 error when running my script tool.

Background of the script:

Earlier in the script, i do a summary statistics and I am editing the fields to get the field alias so the output looks cleaner because later in the script, table to excel is run to export the table. Here is what my script looks like:

fieldList = arcpy.ListFields(in_table)
length = len(fieldList)


arcpy.DeleteField_management(in_table, nodeIDField)

alias_dict = {1: 'Network ID', 2: 'Project ID', 3: 'Municipality', 4: 'Node Count'}

for i, field in enumerate(fieldList):
    if field.type != 'OID':
        newfield = '{}new'.format(field.name)
        arcpy.AddField_management(in_table, newfield, field.type, field.precision,
                                field.scale, field.length, alias_dict[i], field.isNullable, field.required, field.domain)
        arcpy.CalculateField_management(in_table, newfield, '!{}!'.format(field.name), "PYTHON_9.3")
        arcpy.DeleteField_management(in_table, field.name)
‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

When running this, the existing fields do get modified with the alias I want for each, but then get KeyError: 5 error. My thought is that it is because the key 5 does not exist. How do I get the script to just pass through to the next portion of the script if the key of 5 does not exist?

Re: KeyError when working with fields

VishalShah2 — Fri, 10 Dec 2021 22:31:17 GMT

Never mind. I found a working solution.

nodeIDField = "COUNT_ID"

fieldList = arcpy.ListFields(in_table)
length = len(fieldList) - 2

arcpy.DeleteField_management(in_table, nodeIDField)

alias_dict = {1: 'Network ID', 2: 'Project ID', 3: 'Municipality', 4: 'Node Count'}

for i, field in enumerate(fieldList):
    if field.type != 'OID' and i <= length:
        newfield = '{}new'.format(field.name)
        arcpy.AddField_management(in_table, newfield, field.type, field.precision,
                                field.scale, field.length, alias_dict[i], field.isNullable, field.required, field.domain)
        arcpy.CalculateField_management(in_table, newfield, '!{}!'.format(field.name), "PYTHON_9.3")
        arcpy.DeleteField_management(in_table, field.name)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

The original length of the fieldlist was 6, hence why i got KeyError: 5. It was looking for the 5th key in the dictionary. I am subtracting 2 because I do not want to count the ObjectID field or the field I am deleting using arcpy.DeleteField_management.

Re: KeyError when working with fields

JoshuaBixby — Tue, 13 Mar 2018 18:29:38 GMT

If the field isn't in your alias list, do you want it created with no alias or not even created at all?

Re: KeyError when working with fields

VishalShah2 — Tue, 13 Mar 2018 18:58:13 GMT

Not created at all.