On Thu, Feb 21, 2013 at 12:33 PM, Schizoid Man <schiz_...@21stcentury.com> wrote: > Hi there, > > I run the following code in Python 3.3.0 (on a Windows 7 machine) and Python > 2.7.3 on a Mac and I get two different results: > > result1 = [] > result2 = [] > for a in range(2,101): > for b in range(2,101): > result1.append(math.pow(a,b)) > result2.append(a**b) > result1 = list(set(result1)) > result2 = list(set(result2)) > print (len(result1)) > print (len(result2)) > > On the Windows box, I get 9183 for on both lines. However, on the Mac I get > 9220 and 9183. Why this difference? Is there some sort of precision subtlety > I'm missing between ** and math.pow()?
math.pow is basically a wrapper for the C standard pow function, which operates on doubles. The difference you're seeing is probably a difference in implementation in the platform's C library. The ** operator on the other hand is implemented separately as a Python built-in and operates on any numeric data type. -- http://mail.python.org/mailman/listinfo/python-list
