Zipping together entries of a list of lists using Python

Question

If I have a list with multiple lists (for simplicity 3, but I actually have a very large amount):

list = [[1,a,2],[3,b,4],[5,c,6]]

How do I obtain a new lists of lists that combines the original list items based on their positions using Python?

new_list = [[1,3,5],[a,b,c],[2,4,6]]

I've been trying the zip function on "list" but it's not working, what am I doing wrong?

Answer 1

This does what you want.

mylist = [[1,"a",2],[3,"b",4],[5,"c",6]]
mylist2 = list(map(list, zip(*mylist)))

Please don't use list, or any other built-in as variable name.

Try it online!

list(map(list, zip(*mylist)))

                   *mylist    -- unpacks the list
               zip(*mylist)   -- creates an iterable of the unpacked list, 
                                 with the i-th element beeing a tuple 
                                 containing all i-th elements of each element of *mylist
         list                 -- Is the built-in function list()
     map( f  ,   iter      )  -- Applys a function f to all elements of an iterable iter
list(                       ) -- Creates a list from whatever is inside.

Answer 2

You can use zip:

a = 1
b = 2
c = 3
l = [[1,a,2],[3,b,4],[5,c,6]]

new_l = list(map(list, zip(*l)))

Output:

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

Notice that the variables are now displayed in the second element of new_l

Answer 3

You can use zip , also keep in minde it's bad practice to use built-in functions as variable name.

l = [[1,a,2],[3,b,4],[5,c,6]]
list(zip(*l))

output

[[1,3,5],[a,b,c],[2,4,6]]