def mean(self, axis=None, dtype=None, out=None):
return N.ndarray.mean(self, axis, dtype, out, keepdims=True)._collapse(axis)<EOL>
Returns the average of the matrix elements along the given axis.

Refer to `numpy.mean` for full documentation.

See Also
--------
numpy.mean

Notes
-----
Same as `ndarray.mean` except that, where that returns an `ndarray`,
this returns a `matrix` object.

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.mean()
5.5
>>> x.mean(0)
matrix([[ 4.,  5.,  6.,  7.]])
>>> x.mean(1)
matrix([[ 1.5],
        [ 5.5],
        [ 9.5]])