Python math module

python math module import logarithm
user1126849 picture user1126849 · Jan 9, 2012 · Viewed 190.2k times · Source

Whenever I try to use any of the built-in functions of Python's exponentiation and logarithms module, I get an error like this: 

NameError: name 'sqrt' is not defined

I have tried using math.sqrt(4),sqrt(4) and sqrt(4.0), but none of them work. The exception is pow, which works as it's supposed to. This is really strange and I'm not sure what's wrong.

Answer

dave picture dave · Jan 9, 2012

pow is built into the language(not part of the math library). The problem is that you haven't imported math.

Try this:

import math
math.sqrt(4)

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