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]]]
