numpy.roll() in Python

The numpy.roll() function rolls array elements along the specified axis. Basically what happens is that elements of the input array are being shifted. If an element is being rolled first to the last position, it is rolled back to the first position. 

Syntax : 

numpy.roll(array, shift, axis = None)

Parameters : 

array : [array_like][array_like]Input array, whose elements we want to roll
shift : [int or int_tuple]No. of times we need to shift array elements.
        If a tuple, then axis must be a tuple of the same size, and each of the given 
        axes is shifted
        by the corresponding number. 
        If an int while axis is a tuple of ints, then the same value is used for all given axes.
axis  :  [array_like]Plane, along which we wish to roll array or shift it's elements.

Return : 

Output rolled array, with the same shape as a.

Python

# Python Program illustrating
# numpy.roll() method

import numpy as geek

array = geek.arange(12).reshape(3, 4)
print("Original array : \n", array)

# Rolling array; Shifting one place
print("\nRolling with 1 shift : \n", geek.roll(array, 1))

# Rolling array; Shifting five places
print("\nRolling with 5 shift : \n", geek.roll(array, 5))

# Rolling array; Shifting five places with 0th axis
print("\nRolling with 2 shift with 0 axis : \n", geek.roll(array, 2, axis = 0))

Output : 

Original array : 
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]

Rolling with 1 shift : 
 [[11  0  1  2]
 [ 3  4  5  6]
 [ 7  8  9 10]]

Rolling with 5 shift : 
 [[ 7  8  9 10]
 [11  0  1  2]
 [ 3  4  5  6]]

Rolling with 2 shift with 0 axis : 
 [[ 4  5  6  7]
 [ 8  9 10 11]
 [ 0  1  2  3]]

These codes won’t run on online IDE’s. So please, run them on your systems to explore the working.