Question

In Matlab, one can access a column of an array with ::

>> array=[1 2 3; 4 5 6]

array =

     1     2     3
     4     5     6


>> array(:,2)

ans =

     2
     5

How to do this in Python?

>>> array=[[1,2,3],[4,5,6]]
>>> array[:,2]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: list indices must be integers, not tuple
>>> array[:][2]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>

Addendum

I’d like an example applied to an array of dimensions greater than three:

>> B = cat(3, eye(3), ones(3), magic(3))

B(:,:,1) =

     1     0     0
     0     1     0
     0     0     1


B(:,:,2) =

     1     1     1
     1     1     1
     1     1     1


B(:,:,3) =

     8     1     6
     3     5     7
     4     9     2

>> B(:,:,1)                             

ans =

     1     0     0
     0     1     0
     0     0     1

>> B(:,2,:)

ans(:,:,1) =

     0
     1
     0


ans(:,:,2) =

     1
     1
     1


ans(:,:,3) =

     1
     5
     9

Answer 1

Use Numpy.

>>> import numpy as np
>>> 
>>> a = np.array([[1,2,3],[4,5,6]])
>>> a[:, 2]
array([3, 6])

If you come from Matlab, this should be of interest: Link