Assigning values to field based on values in other field using Python Parser of ArcGIS Field Calculator? [duplicate]

Question

I have a table with two fields A and B, and i want fill field B with "some values" from field A:

FieldA: 123456_CC; 123_D; 1234567_AB; 123456768_F

I just need the "text" that is associated with the value of the field

FieldB: CC; D; AB; F

What expression to create this?

Answer 1

Assuming all of your row values are in the form chunkA_chunkB, you can use the following expression in the field calculator:

!yourField!.split("_")[1]

This method actually breaks the string into a list of selectable items. To illustrate, in the python interpreter:

>>> row1 = '123456_CC'
>>> row1.split("_")
['123456', 'CC']

And to select just the second item in the list:

>>> row1.split("_")[1]
'CC'