Peak-to-peak (maximum - minimum) value along the given axis.
Refer to numpy.ptp for full documentation.
See also
Notes
Same as ndarray.ptp, except, where that would return an ndarray object, 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.ptp()
11
>>> x.ptp(0)
matrix([[8, 8, 8, 8]])
>>> x.ptp(1)
matrix([[3],
[3],
[3]])