Question

so I have this list in python,

a=  [[1,2,3,4],
     [2,4,5,1],
     [3,4,6,2],
     [2,3,4,5]]

and want to turn the list reading horizontally to vertically.

b=    [[1,2,3,2],
       [2,4,4,3],
       [3,5,6,4],
       [4,1,2,5]]

what is the best way to do it, and most efficient way to do it? i’m pretty new to programming, sorry for being noob. thanks.

Answer 1

You can do it like that:

zip(*your_list)

Proof:

>>> a = [[1, 2, 3, 4], [2, 4, 5, 1], [3, 4, 6, 2], [2, 3, 4, 5]]
>>> zip(*a)
[(1, 2, 3, 2), (2, 4, 4, 3), (3, 5, 6, 4), (4, 1, 2, 5)]