Extracting Columns from numpy array

Question

Assuming I have a numpy array

A = np.array([[1,2,3,4],[5,6,7,8]])

and I want to access it row wise I can do

for row in A:
  print(row)

which results in me having

[1 2 3 4]
[5 6 7 8]

Is there a similar column wise method to access the array which will result in me having

[1 5]
[2 6]
[3 7]
[4 8]

I know I can use indices but, I just want to know if there is a way to access the array column wise without indices.

Thanks

Bi Rico · Accepted Answer · 2015-06-01 23:54:33Z

2

Transposing the array should get you what you want:

for item in A.T:
    print(item)

The T proprety is short for the transpose() method and returns a view on the array.

answered Jun 1, 2015 at 23:54

Bi Rico

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Comments

Praveen · Accepted Answer · 2015-06-02 00:45:53Z

0

You could select the ith column of A, like so:

for i in range(A.shape[1]):
    print(A[:, i])

answered Jun 2, 2015 at 0:45

Praveen

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sorry I do not want to use indices