numpy.matrix.var#

method

matrix.var(axis=None, dtype=None, out=None, ddof=0)[原始碼]#

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

Refer to numpy.var for full documentation.

也參考

numpy.var

Notes

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

Examples

>>> x = np.matrix(np.arange(12).reshape((3, 4)))
>>> x
matrix([[ 0,  1,  2,  3],
        [ 4,  5,  6,  7],
        [ 8,  9, 10, 11]])
>>> x.var()
11.916666666666666
>>> x.var(0)
matrix([[ 10.66666667,  10.66666667,  10.66666667,  10.66666667]]) # may vary
>>> x.var(1)
matrix([[1.25],
        [1.25],
        [1.25]])