Field Calculator- Delete last 3 text characters

Question

Hello,

I have postcodes which I need to cut down from say BN14 5RY to only BN14. I cannot simply use the 'left(input, n)' equation as some postcodes are only 6 figures long such as BN1 5RY and I always need the first 3/4 characters.

Does anyone know a way to delete the last 3 characters?

Thanks in advance.

gpnobbir · Answer

If there is always a space between first 3/4 characters and last 3 characters you can split the string and take the first part:
 
"BN14 5RY".split()[0]

# or

"BN1 5RY".split()[0]

RichardFairhurst · Answer

If your field contains string/text data, there is no need for the len method in Python since string data is an "iterable".  For example>>> a = "abcdefghijklmnop"
>>> b = a[:-4]
>>> b
'abcdefghijkl'
>>>

Dan:

I am not really a Python programmer and my expression above would not work anyway because I didn't notice (in my quick check of some Python websites) that I needed the colon to indicate to take everything from the beginning of the string to the second position.  Thanks for correcting my Python ignorance and showing another example of where Python is more elegant than VB Script.

DanPatterson_Retired · Answer

If your field contains string/text data, there is no need for the len method in Python since string data is an "iterable".  For example>>> a = "abcdefghijklmnop"
>>> b = a[:-4]
>>> b
'abcdefghijkl'
>>>