GCD in standard library?

Skip Montanaro skip at pobox.com
Thu Mar 13 02:20:58 CET 2003

    Blake> I'm just guessing it is very common for people to have to add
    Blake> this to their programs:

    Blake> def gcd(x,y):
    Blake>   if x % y == 0: return y
    Blake>   else: return gcd(y,x%y)

Depends on what field you're in.  I have been programming in Python for nine
or ten years and have never once had the need for a gcd function.

As for adding it to the math module, that goes against the typical grain of
Python's core extension modules.  They generally expose functions in a
corresponding Unix C library.  Since there's no gcd in the Unix math (-lm)
library, there's no gcd() in the math module.


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