Check if all sides of a multidimensional numpy array are arrays of zeros

Question

An n-dimensional array has 2n sides (a 1-dimensional array has 2 endpoints; a 2-dimensional array has 4 sides or edges; a 3-dimensional array has 6 2-dimensional faces; a 4-dime

Answer 1

maybe the ellipsis operator is what you are looking for, which will work for many dimensions:

import numpy as np

# data
x = np.random.rand(2, 5, 5)
x[..., 0:, 0] = 0
x[..., 0, 0:] = 0
x[..., 0:, -1] = 0
x[..., -1, 0:] = 0

test = np.all(
    [
        np.all(x[..., 0:, 0] == 0),
        np.all(x[..., 0, 0:] == 0),
        np.all(x[..., 0:, -1] == 0),
        np.all(x[..., -1, 0:] == 0),
    ]
)

print(test)