The function you’re after is numpy.linalg.norm
. (I reckon it should be in base numpy as a property of an array — say x.norm()
— but oh well).
import numpy as np
x = np.array([1,2,3,4,5])
np.linalg.norm(x)
You can also feed in an optional ord
for the nth order norm you want. Say you wanted the 1-norm:
np.linalg.norm(x,ord=1)
And so on.