Numpy binary matrix - get rows and columns of True elements

Question

I have a binary numpy 2D array, say,

import numpy as np
arr = np.array([
#   Col 0   Col 1  Col 2
    [False, False, True],  # Row 0
    [True, False, False]         


        

Answer 1

You are looking for np.argwhere -

np.argwhere(arr)

Sample run -

In [220]: arr
Out[220]: 
array([[False, False,  True],
       [ True, False, False],
       [ True,  True, False]], dtype=bool)

In [221]: np.argwhere(arr)
Out[221]: 
array([[0, 2],
       [1, 0],
       [2, 0],
       [2, 1]])