Question

How to extract an arithmetic root of arbitrary degree in Python?
I know that algorithm:

z = pow(x,(1/N))

Is this correct?
Is this the only way?

Answer 1

This is indeed the way to go. However, you need to use 1.0/N to ensure float division (unless N is always a float):

>>> import math
>>> math.pow(27, 1/3)
1.0
>>> math.pow(27, 1.0/3)
3.0
>>> math.pow(27, 1/3.0)
3.0

You could also use from __future__ import division to make / the “regular” division operator (for integer division you would then use //):

>>> from __future__ import division
>>> import math
>>> math.pow(27, 1/3)
3.0

Instead of math.pow(x, y) you could also use the x ** y operator:

>>> 27**(1.0/3)
3.0