I'm pretty new to scripting with Python.

My code is intending to iterate through a list of feature classes within a GDB, creating the fields EF_Type and EF_Group, then calculating the field. The values of 'EF_Group' will be dependent on the values of EF_Type (ex: the feature classes 'Local EOCs' and 'State EOCs' will both have the value of 'EOC' in the 'EF_Group' field.

I created an update cursor to iterate through the feature classes and update the values of 'EF_Group.' The script runs without an error message, but when I open the attribute tables within Pro, 'EF_Group' remains NULL.


    arcpy.AddField_management (fc, 'EF_Type', 'TEXT')

    EFType = arcpy.CalculateField_management(fc, 'EF_Type', '"' + name + '"') #Renames field EF_Type to the first 2 words pulled using the split format tool
    arcpy.AddField_management (fc, 'EF_Group', 'TEXT')

    fields= ['EF_Type', 'EF_Group']

    with arcpy.da.UpdateCursor(fc, fields) as cursor: #Update cursor will use 1st field (EF_Type) to build 2nd field (EF_Group)
        for row in cursor:
            if fields[0] == 'Local EOCs' or fields[0] == 'State EOCs':
                fields[1] = 'EOC'
            elif fields[0] == 'Fire Stations':
                fields[1] = 'Fire'
            elif fields[0] == 'Public Schools' or fields[0] == 'Private Schools' or fields[0] == 'DayCare Centers' or fields[0] == 'Colleges Universities':
                fields[1] = 'School'
            elif fields[0] == 'UrgentCare Centers' or fields[0] == 'Nursing Homes' or fields[0] == 'Hospitals Intersect':
                fields[1] = 'Care'
            elif fields[0] == 'LawEnforcement Locations':
                fields[1] = 'Law'
  • 4
    You never actually change the row object. You're only changing fields, but you need to change row.
    – phloem
    Commented Jun 1, 2018 at 18:31
  • 1
    At first glance it looks you may want to change fields[x] to row[x] where x is 0 or 1
    – ZrSiO4
    Commented Jun 1, 2018 at 18:34

1 Answer 1


You need to interact with the row object, not fields. Consider the example from UpdateCursor:

import arcpy

fc = 'c:/data/base.gdb/well'
fields = ['WELL_YIELD', 'WELL_CLASS']

# Create update cursor for feature class 
with arcpy.da.UpdateCursor(fc, fields) as cursor:
    # For each row, evaluate the WELL_YIELD value (index position 
    # of 0), and update WELL_CLASS (index position of 1)
    for row in cursor:
        if (row[0] >= 0 and row[0] <= 10):
            row[1] = 1
        elif (row[0] > 10 and row[0] <= 20):
            row[1] = 2
        elif (row[0] > 20 and row[0] <= 30):
            row[1] = 3
        elif (row[0] > 30):
            row[1] = 4

        # Update the cursor with the updated list

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