Change the shape of an array using another array

Question

I want to reshape one array using other array.

Say I have array_1, whose shape is (5, 1), e.g.:

>>> array_1
array([[ 0.33333333],
       [ 0.36666667],
       [ 0.16666667],
       [ 0.06666667],
       [ 0.06666667]]

and array_2, whose shape is (1, 5). I want to reshape array_1 so that it gets the shape of array_2. The shape of array_2 can change every time I run the code.

@jonrsharpe sorry but had to roll back because the example got removed. — Anand S Kumar
– Anand S Kumar, Commented Jul 21, 2015 at 9:56
@AnandSKumar no, you didn't; you could have done what I just did, i.e. edit the example into the improved post — jonrsharpe
– jonrsharpe, Commented Jul 21, 2015 at 9:56

jonrsharpe · Accepted Answer · 2015-07-21 09:57:19Z

5

Assuming numpy arrays, just use array_1.reshape(array_2.shape):

>>> import numpy as np
>>> arr1 = np.arange(5).reshape(5, 1)
>>> arr2 = np.arange(5, 10).reshape(1, 5)
>>> arr1
array([[0],
       [1],
       [2],
       [3],
       [4]])
>>> arr2
array([[5, 6, 7, 8, 9]])
>>> arr1.reshape(arr2.shape)
array([[0, 1, 2, 3, 4]])
>>> arr2.reshape(arr1.shape)
array([[5],
       [6],
       [7],
       [8],
       [9]])

Note that this is not in-place; it creates a new array, so you would need to assign e.g. array_1 = array_1.reshape(...).

edited Jul 21, 2015 at 9:57

answered Jul 21, 2015 at 9:51

jonrsharpe

123k31 gold badges277 silver badges488 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Geeocode · Accepted Answer · 2015-07-21 10:11:19Z

2

You simply should use numpy.transpose in this case:

import numpy as np

array_1 = [[ 0.33333333],
 [ 0.36666667],
 [ 0.16666667],
 [ 0.06666667],
 [ 0.06666667]]

print "Shape of original array_1: ", np.shape(array_1)

array_1 = np.transpose(array_1)

print array_1
print "Shape of transposed array_1: ", np.shape(array_1)

Output:

Shape of original array_1:  (5, 1)
[[ 0.33333333  0.36666667  0.16666667  0.06666667  0.06666667]]
Shape of transposed array_1:  (1, 5)

edited Jul 21, 2015 at 10:11

answered Jul 21, 2015 at 9:55

Geeocode

5,8173 gold badges22 silver badges35 bronze badges

Collectives™ on Stack Overflow

Change the shape of an array using another array

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related