scipy.sparse.dok_matrix.nonzero#

dok_matrix.nonzero()[source]#

Nonzero indices of the array/matrix.

Returns a tuple of arrays (row,col) containing the indices of the non-zero elements of the array.

Examples

>>> from scipy.sparse import csr_array
>>> A = csr_array([[1,2,0],[0,0,3],[4,0,5]])
>>> A.nonzero()
(array([0, 0, 1, 2, 2]), array([0, 1, 2, 0, 2]))