Transpose list of lists

Question

Let\'s take:

l = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

The result I\'m looking for is

r = [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
         


        

Answer 1

just for fun, valid rectangles and assuming that m[0] exists

>>> m = [[1,2,3],[4,5,6],[7,8,9]]
>>> [[row[i] for row in m] for i in range(len(m[0]))]
[[1, 4, 7], [2, 5, 8], [3, 6, 9]]