Python printing a 2d list from top to bottom

Question

I have a list given:

grid = [['.', '.', '.', '.', '.', '.'],
    ['.', '0', '0', '.', '.', '.'],
    ['0', '0', '0', '0', '.', '.'],
    ['0', '0', '0', '0', '0', '.'],
    ['.', '0', '0', '0', '0', '0'],
    ['0', '0', '0', '0', '0', '.'],
    ['0', '0', '0', '0', '.', '.'],
    ['.', '0', '0', '.', '.', '.'],
    ['.', '.', '.', '.', '.', '.']]

and I want to print it like this:

..00.00..
.0000000.
.0000000.
..00000..
...000...
....0....

I tried it with the following code but it will give me always a

i = 0
j = 0
while i < len(grid):    
    while j < len(grid[j]):
        if i == len(grid)-1:
            print(grid[i][j])
            j = j + 1
        else:
            print(grid[i][j], end='')
            i = i + 1

IndexError: list index out of range

What can I do?

Answer 1

You want the columns so use zip to get the columns then concatenate the items using str.join() method within a list comprehension to form the lines and finally join the lines with new-line characters.:

In [89]: print('\n'.join([''.join(c) for c in zip(*grid)]))

..00.00..
.0000000.
.0000000.
..00000..
...000...
....0....