Calculate Field to update a column based on not null in another column

Question

Calculate Fields

(i"m new to arcpy and arcgispro)

I'm attempting to use the Calculate Field to update a column based on non-null values in another column:

Expression:
UpdateLoc(!GAZETTED_LOCALITY_NAME!)

Code Block:
def UpdateLoc(nameGaz):
    if (nameGaz != none):
        return 'L'

(I've tried != NULL and IS NOT NULL as well)

I'm not sure where I am going wrong here, I get '2 parameters are missing or invalid'

deleted-user-1sAsOmMajBua · Answer

Thanks for that - it wasn't clear what went in what box from the example I ripped off (Calculate Field Python examples—Data Management toolbox | ArcGIS Desktop ).

DanPatterson_Retired · Answer

and if you want to use your code block, you don't include the …. Expression : nor the Code block lines, Underneath Type (which is the field you are trying to calculate values for, you put the expression in there Type: ---------------------------------- UpdateLoc(!GAZETTED_LOCALITY_NAME!) Then in the code block section Code Block ---------------------------- def UpdateLoc(nameGaz): if nameGaz is not None: return 'L'‍‍‍ return None‍‍‍‍ code blocks and expression lines take a bit of getting used to. If you reuse and expression a lot, you can save them a *.cal files, and then reload them

JoshuaBixby · Answer

For this type of basic conditional check, you don't need a code block. Set the parser to Python and try the following expression: 'L' if !GAZETTED_LOCALITY_NAME! is not None else None‍‍‍ NULL in databases and data stores gets mapped to Python None.