numpy.argwhere — NumPy v2.2 Manual (original) (raw)

numpy.argwhere(a)[source]#

Find the indices of array elements that are non-zero, grouped by element.

Parameters:

aarray_like

Input data.

Returns:

index_array(N, a.ndim) ndarray

Indices of elements that are non-zero. Indices are grouped by element. This array will have shape (N, a.ndim) where N is the number of non-zero items.

Notes

np.argwhere(a) is almost the same as np.transpose(np.nonzero(a)), but produces a result of the correct shape for a 0D array.

The output of argwhere is not suitable for indexing arrays. For this purpose use nonzero(a) instead.

Examples

import numpy as np x = np.arange(6).reshape(2,3) x array([[0, 1, 2], [3, 4, 5]]) np.argwhere(x>1) array([[0, 2], [1, 0], [1, 1], [1, 2]])