Positive, Negative or zero in a 2D array python
You should choose better functions names, function does not give any indication what the purpose of the function is.
In addition, a docstring comment can be used to give a short description.
But actually there is no need for a custom function because numpy.sign already provides the exact functionality:

Returns an element-wise indication of the sign of a number.

Example:
import numpy as np

array = np.random.randint(-10,10, size=(4,4))
print(np.sign(array))

Output:

[[-1  1  1  1]
 [ 1  1  0  0]
 [ 1  1 -1  1]
 [ 1 -1  1 -1]]