How can I calculate an outer function in python?

Question

If I have a random function like func(x,y) = cos(x) + sen(y) + x*y how can I apply it to all the pairs of elements in 2 arrays?

I found https://docs.scipy.org/doc/nu

Answer 1

One way to solve this is broadcasting:

import numpy as np

def func(x, y):
    x, y = np.asarray(x)[:, None], np.asarray(y)
    return np.cos(x) + np.sin(y) + x*y

The [:, None] adds another dimension to an array and therefor triggers NumPys broadcasting.

>>> func([1,2], [3,4])
array([[ 3.68142231,  3.78349981],
       [ 5.72497317,  6.82705067]])