topic Using OR statement i Field Calculator in Geoprocessing Questions

Using OR statement i Field Calculator

GjermundDeggerdal — Thu, 08 Apr 2021 18:10:28 GMT

I am using ArcMAP 10.8 and i am trying to add a new field to a table. So far so good..

In this new field i want a number between 1 and 5. The number is decided based on what is written in three other fields in the table ([MATERIAL], [YEAR] and [DIM]) So therefore i am using the Field Calculator. My problem is that i have never gotten the OR statement to work without writing the whole code again.

Therefore I have to write it like this to work:

dim n
if [DIM]=< 100 and [YEAR] =< 1959 and [MATERIAL] = "SJG" or [DIM]=< 100 and [YEAR] =< 1959 and [MATERIAL] = "SJ" then
n = 5

But, I want to write it like this (or something similar);

dim n
if [DIM]=< 100 and [YEAR] =< 1959 and [MATERIAL] = "SJG", "SJ" then
n = 5

I would really appriciate if there is some solution to this problem 😉

Re: Using OR statement i Field Calculator

Jelle_Stu_PR — Fri, 09 Apr 2021 12:35:01 GMT

I would use a python a script by setting the expression type to python.

Expression:

reclass(!DIM!,!YEAR!,!MATERIAL!):

code block:

def reclass(dim, year, material): if dim <= 100 and year <= 1959 and material in ("SJG", "SJ"): return 5

Re: Using OR statement i Field Calculator

JayantaPoddar — Fri, 09 Apr 2021 05:41:01 GMT

This has also worked for me (Parser: Python).

Code Block:

def reclass(dim,year,material): if dim<=100 and year<=1959 and material in ("SJG","SJ"): return 5

Expression:

reclass( !DIM!, !YEAR!, !MATERIAL! )

Re: Using OR statement i Field Calculator

GjermundDeggerdal — Fri, 09 Apr 2021 07:15:50 GMT

Thank you very much for your helpfull respons! I am truly sorry if my follow-up questions are stupid and basic, but I`m stuck.

I have probably done something wrong, because I can`t get this command to work. I wrote it in like this (Copy - paste from your post). Is there something more I have to add to the statement?

And I dont understand why you don`t need exclamation marks around the variable inside the pre logic script, this seems diffrent then in VB Script?

Re: Using OR statement i Field Calculator

JayantaPoddar — Fri, 09 Apr 2021 07:40:10 GMT

In Pre-logic Script, it's just a variable name used in the function. In the expression those variable named get replaced by actual Field Names.

In Expression, delete the fieldnames, and add them again by double-clicking the appropriate items in the Fields list, separated by comma.

Also you won't get any result, if the logic is not true for any record.

Re: Using OR statement i Field Calculator

GjermundDeggerdal — Fri, 09 Apr 2021 12:14:20 GMT

Thanks, Your code worked perfect with copy-paste, the problem was that i had empty values "Null" and shape did not allow it. I converted it to gdb and it worked right away! Cheers!