Parameters to numpy's fromfunction

Question

I haven\'t grokked the key concepts in numpy yet.

I would like to create a 3-dimensional array and populate each cell with the result of a function call

Answer 1

Here's my take on your problem:

As mentioned by Chris Jones the core of the solution is to use np.vectorize.

# Define your function just like you would
def sum_indices(x, y, z):
    return x + y + z

# Then transform it into a vectorized lambda function
f = sum_indices
fv = np.vectorize(f)

If you now do np.fromfunction(fv, (3, 3, 3)) you get this:

array([[[0., 1., 2.],
        [1., 2., 3.],
        [2., 3., 4.]],

       [[1., 2., 3.],
        [2., 3., 4.],
        [3., 4., 5.]],

       [[2., 3., 4.],
        [3., 4., 5.],
        [4., 5., 6.]]])

Is this what you wanted?