python - Access matrix by list of matrix indices in Numpy -


i have list of matrix indices , want access matrix these indices.

example:

indices = [(2, 0), (2, 1), (2, 2)] mat = [[1, 2, 3], [4, 5, 6], [7, 8, 9]] mat[indices] = 0

this should result in [[1, 2, 3], [4, 5, 6], [0, 0, 0]], unfortunately "list indices must integers, not list".

edit

as user2357112 suggests in comment tried following now:

mat = numpy.array(mat) indices = numpy.array(indices) mat[indices] = 0

but unfortunately whole matrix filled 0 now.

indices regular list of tuples , can't used element of regular mat. can iterate on list indices:

for x, y in indices:     mat[x][y] = 0

if want use numpy methods, need create numpy array. indeed, np.array structure allows use tuple access element:

mat = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) item in indices:     mat[item] = 0

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