rotate_matrix_90_degrees.py

#!/usr/bin/env python3

from rotate_testcases import *#kludge


def rotate_matrix_90_deg_right(matrix):
    outer_list = []
    matrix = list(reversed(matrix))
    matrix_len = len(matrix)
    max_row_len = max([len(row) for row in matrix])#should be same len
    if matrix_len >= max_row_len:
        for i in range(0, matrix_len):
            lst = []
            for row in matrix:
                if i < len(row):
                    lst.append(row[i])
                if len(lst) == len(row):
                    outer_list.append(lst)
    else:
        for i in range(0, max_row_len):
            lst = []
            for j in range(0, matrix_len):
                lst.append(matrix[j][i])
            outer_list.append(lst)
    return outer_list


if __name__ == '__main__':
    assert(rotate_matrix_90_deg_right(M1) == M1OUT)
    assert(rotate_matrix_90_deg_right(M2) == M2OUT)
    assert(rotate_matrix_90_deg_right(M3) == M3OUT)

rotate_testcases.py

M1 = [
    [1,2,3],
    [4,5,6],
    [7,8,9],
    [10,11,12],
]


M1OUT = [
    [10,7,4,1],
    [11,8,5,2],
    [12,9,6,3],
]


M2 = [
    [4,5,6],
    [7,8,9],
    [10,11,12],
]


M2OUT = [
    [10,7,4],
    [11,8,5],
    [12,9,6],
]


M3 = [
    [4,5,6],
    [7,8,9],
]


M3OUT = [
    [7,4],
    [8,5],
    [9,6],
]