Is there an easily available implementation of erf() for Python?

Question

I can implement the error function, erf, myself, but I\'d prefer not to. Is there a python package with no external dependencies that contains an implementation of this func

Answer 1

SciPy has an implementation of the erf function, see scipy.special.erf.

Answer 2

One note for those aiming for higher performance: vectorize, if possible.

import numpy as np
from scipy.special import erf

def vectorized(n):
    x = np.random.randn(n)
    return erf(x)

def loopstyle(n):
    x = np.random.randn(n)
    return [erf(v) for v in x]

%timeit vectorized(10e5)
%timeit loopstyle(10e5)

gives results

# vectorized
10 loops, best of 3: 108 ms per loop

# loops
1 loops, best of 3: 2.34 s per loop