How will you sort the array based on the Nth column?

For example, consider an array arr.

 

arr = np.array([[8, 3, 2],

[3, 6, 5],

[6, 1, 4]])

Let us try to sort the rows by the 2nd column so that we get:

 

[[6, 1, 4],

[8, 3, 2],

[3, 6, 5]]

We can do this by using the sort() method in numpy as:

 

import numpy as np

arr = np.array([[8, 3, 2],

[3, 6, 5],

[6, 1, 4]])

#sort the array using np.sort

arr = np.sort(arr.view('i8,i8,i8'),

order=['f1'],

axis=0).view(np.int)

We can also perform sorting and that too inplace sorting by doing:

 

arr.view('i8,i8,i8').sort(order=['f1'], axis=0)