How to convert single number into 3 digit code using Python and field calculator?

Question

I have three fields in an attribute table that I have combined through the field calculator to generate one value in my 'name field'. It displays like this - 'RSB01-1'. However, I want the final digit to display as a three digit code e.g 001 instead of just 1. What python function do I use in the field calculator?

The code I have looks like this : ''.join([ !NRS!, !NSA!, "-", str(!SeqNo!)] )

I know some function is needed around the final field (str(!SeqNo!), I jut don't know what.

Luke_Pinner · Answer

String formatting is good but I always forget the more complex format codes and have to look it up and experiment every time. Might be simpler to use the zfill function:

str(!SeqNo!).zfill(3)

"{}{}-{}".format(!NRS!, !NSA!, str(!SeqNo!).zfill(3))

https://docs.python.org/2/library/string.html

DanPatterson_Retired · Answer

Python parser, with pre-padding as a field calculator expression. Just replace 'a', 'b', 'c' with your field names in ! demo a = 'first_' b = 'second' c = 1 "{}{}-{:>03.0f}".format(a, b, c) 'first_second-001' c = 10 "{}{}-{:>03.0f}".format(a, b, c) 'first_second-010' # --- for fields a, b, c, just use python parser !YourFirstField!, etc‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

bixb0012 · Answer

There are plenty of ways to go about this task. You could just change your existing code to: ''.join([!NRS!, !NSA!, "-", ("00" + str(!SeqNo!))[-3:]])‍