topic Re: arcpy.CalculateField_management) is not passing variable in Python Questions

arcpy.CalculateField_management) is not passing variable

ClaudineSicker — Sun, 12 Dec 2021 00:22:43 GMT

Running as python script within toolbox in ArcGIS 10.1. Trying to say that if file is empty, populate the fields "TypeName","PERCENTAGE", "Region" with the following values: nameVariable, 0, "Georgia", otherwise, populate the table fields "Region" with "Georgia" and the field "TypeName" with "Goldfish". I cannot seem to populate the TypeName field with a variable. What am I doing wrong. I have spent two days on this and I cannot figure it out!

# Geonet conversion put code in a single line.  Below is another user's attempt to get python indentation
# fixed to make sense of the "answer".  Should be good thru line 20....not sure after that.

import os.path 
import arcpy 
import arcgisscripting  
myList = ("Fish", "Reptile","Aracnid", "Other") 
geoLoc = "C:\\Data\\TempData.gdb\\"  
for variablefile in myList:
  #  Assigning variables      
  species = geoLoc + (variablefile)+ "_Buffer"  
  # setting nameVariable     
  if variablefile == "Fish":
    nameVariable = "Goldfish"
  elif variablefile == "Reptile":
    nameVariable = "Tree frog"
  elif variablefile == "Aracnid":
    nameVariable = "Black widow"
  else:
    nameVariable = "Household pet"
  addRow =arcpy.da.InsertCursor(species,("TypeName","PERCENTAGE", "Region"))
  result = int(arcpy.GetCount_management(species).getOutput(0))
  if result == 0:
    addRow.insertRow((nameVariable, 0, "Georgia"))
  else:
    arcpy.CalculateField_management(species, "Region", "\"Georgia\"", "PYTHON", "")
    arcpy.CalculateField_management(species, "TypeName", 'nameVariable', "PYTHON", "")
    #arcpy.CalculateField_management(species, "Name", "\"Goldfish\"", "PYTHON", "")  Works but doesn't use variable name     
exit

I get the following error message:

ExecuteError: ERROR 000539: Error running expression: commonName
Traceback (most recent call last):
File "<expression>", line 1, in <module>
NameError: name 'commonName' is not defined

Pretty sure it is failing at nameVariable (bold).

Thanks in advance.

Question from Mar 8, 2013 6:51 PM Message was edited by: Timothy Hales Formatted Code Block

Message was edited by: Timothy Hales

Re: arcpy.CalculateField_management) is not passing variable

ClaudineSicker — Sun, 10 Mar 2013 01:20:27 GMT

Oops. Sorry. Copied wrong message. (That happens when you spend days on a single line of code. You get punchy and careless.) The actual message is:

ExecuteError: ERROR 000539: Error running expression: nameVariable
Traceback (most recent call last):
File "<expression>", line 1, in <module>
NameError: name 'nameVariable' is not defined

Happens on last executable line before "Exit"

Still stuck on this. Can't figure out how to get it to do what I want. Hopefully with the correct error message, someone can figure this out for me. I don't know where to go from here.

Re: arcpy.CalculateField_management) is not passing variable

ClaudineSicker — Sun, 10 Mar 2013 02:28:32 GMT

Had a eureka moment and figured it out. Correct format is:

arcpy.CalculateField_management(species, "TypeName", "\"nameVariable\"", "PYTHON", "")

Woohoo!

Re: arcpy.CalculateField_management) is not passing variable

curtvprice — Sun, 10 Mar 2013 04:32:57 GMT

Woohoo!

I highly recommend using nested quotes and substitution - easier to read and debug. This is equivalent to your solution:

arcpy.CalculateField_management(species, "TypeName", \     '"{0}"'.format(nameVariable), "PYTHON")