Calculate the difference between maximum and minimum elements of Numpy array

Question

Is there any function to calculate the difference between the maximum and the minimum elements of a Numpy array?

Answer 1

You can first find the maximum and minimum values and then subtract them. There is also a Numpy function ptp() [Peak to peak] that returns "maximum - minimum" value along a given axis.

Here are examples:

>>> import numpy as np
>>> aa
array([ 8, 11, 21, 34, 45, 25, 98, 67])
>>> np.ptp(aa)
90
>>> bb
array([[11, 12, 13],
       [14, 15, 16],
       [17, 18, 19],
       [20, 21, 22]])
>>> np.ptp(bb, axis=0)
array([9, 9, 9])
>>> np.ptp(bb, axis=1)
array([2, 2, 2, 2])
>>> np.max(bb, axis=0) - np.min(bb, axis=0)
array([9, 9, 9])
>>> np.max(bb, axis=1) - np.min(bb, axis=1)
array([2, 2, 2, 2])
>>>