numpy.matrix.sum

method

matrix.sum(self, axis=None, dtype=None, out=None) [source]

Returns the sum of the matrix elements, along the given axis.

Refer to numpy.sum for full documentation.

See also

numpy.sum

Notes

This is the same as ndarray.sum, except that where an ndarray would be returned, a matrix object is returned instead.

Examples

>>> x = np.matrix([[1, 2], [4, 3]])
>>> x.sum()
10
>>> x.sum(axis=1)
matrix([[3],
        [7]])
>>> x.sum(axis=1, dtype='float')
matrix([[3.],
        [7.]])
>>> out = np.zeros((2, 1), dtype='float')
>>> x.sum(axis=1, dtype='float', out=np.asmatrix(out))
matrix([[3.],
        [7.]])