numpy.argwhere () in Python



numpy.argwhere() is used to find non-zero indices of array elements grouped by element.

Syntax: numpy.argwhere (arr)

Parameters:
arr: [array_like] Input array.

Return: [ndarray] Indices of elements that are non-zero. Indices are grouped by element.

Code # 1:

# Python program, explaining
# argwhere () function

 

import numpy as geek

  
# input array

in_arr = [[ 2 , 0 , 7 ], [ 0 , 5 , 9 ]]

print ( "Input array:" , in_arr) 

 

out_arr = geek.argwhere (in_arr)

print ( "Output indices of non zero array element:" , out_arr)

Output:

 Input array: [[2, 0, 7 ], [0, 5, 9]] Output indices of non zero array element: [[0 0] [0 2] [1 1] [1 2]] 

Code # 2:

# Python program explaining
Function # argwhere ()

 

impo rt numpy as geek

 
# input array

in_arr = geek.arange ( 8 ). reshape ( 4 , 2 )

print ( "Input array:" , in_arr) 

 

out_arr = geek.argwhere (in_arr & gt; 4 )

print ( "Output indices greater than 4:" , out_arr)

Exit:

 Input array: [[0 1] [2 3] [ 4 5] [6 7]] Output indices greater than 4: [[2 1] [3 0] [3 1]]