numpy.flatnonzero() in Python

numpy.flatnonzero()function is used to Compute indices that are non-zero in the flattened version of arr.

Syntax : numpy.flatnonzero(arr) Parameters : arr : [array_like] Input array. Return : ndarray Output array, containing the indices of the elements of arr.ravel() that are non-zero.

Code #1 : Working Output :

Input array : [-3 -2 -1 0 1 2 3]
Indices of non zero elements : [0 1 2 4 5 6]

  Code #2 : Using the indices of the non-zero elements as an index array.

Output :

Output array of non-zero number: [-3 -2 -1 1 2 3]