numpy.rollaxis() in Python
numpy.rollaxis() in Python
The numpy.rollaxis() function rolls the given axis backwards until it lies in the specified position.
Syntax
numpy.rollaxis(a, axis, start=0)
Parameter
The numpy. rollaxis() method consists of three parameters, which are as follows:
a : It represents an input array.
axis : The parameter axis is used to roll backwards. The positions of the other axes do not change relative to one another.
start : It is an optional integer parameter. The axis is rolled until it lies before the start position. The default value is 0, which signifies a “complete” roll.
Return
This function returns a view of parameter ‘a’.
Example 1
# Python Program explaining # numpy.rollaxis() function import numpy as np arr = np.arange(8).reshape(2,2,2) print ('The original array:') print (arr) # to roll from axis-2 to axis-0 print ('Applying rollaxis() function:') print (np.rollaxis(arr,2) ) # to roll from axis 0 to 1 (along width to height) print('Applying rollaxis() function:' ) print (np.rollaxis(arr,2,1))
Output
The original array: [[[0 1] [2 3]] [[4 5] [6 7]]] Applying rollaxis() function: [[[0 2] [4 6]] [[1 3] [5 7]]] Applying rollaxis() function: [[[0 2] [1 3]] [[4 6] [5 7]]]