2D Array Problem

2d_array.py

test_array = [
    [1,  2,  3,  4],
    [5,  6,  7,  8],
    [9, 10, 11, 12],
]


# [2][0]
# [1][0] [2][1]
# [0][0] [1][1] [2][2]
# [0][1] ...
# [0][2]
# [0][3]


def coord_on_array(array, x, y):
    return (
        x >= 0
        and y >= 0
        and y < len(array)
        and x < len(array[y])
    )


def get_starting_coords(array):
    y = len(array) - 1
    x = 0

    while coord_on_array(array, x, y):
        yield x, y
        y -= 1

    y += 1

    while coord_on_array(array, x, y):
        x += 1
        yield x, y


def get_diagonal_for_starting_coord(array, x, y):
    while coord_on_array(array, x, y):
        yield array[y][x]
        x += 1
        y += 1


def print_diagonals(array):
    """Print the diagonals from an array."""
    for x, y in get_starting_coords(array):
        diag = get_diagonal_for_starting_coord(array, x, y)
        for item in diag:
            print(item, end=' ')
        print()


print_diagonals(test_array)