在嵌套列表中交换列(Python 3)

Question

使用这样的嵌套列表:

N = [['D','C','A','B'],
     [2,3,4,5],
     [6,7,8,9]]

我怎么能交换两列？例如C列和A列.

Answer 1

有了这个帖子的for循环和一点帮助:

码:

N = [["D","C","A","B"],
     [2,3,4,5],
     [6,7,8,9]]

# Swap the last two columns

for item in N:
    item[2], item[3] = item[3], item[2]

# Or as a function

def swap_columns(your_list, pos1, pos2):
    for item in your_list:
        item[pos1], item[pos2] = item[pos2], item[pos1]

输出:

swap_columns(N, 2, 3)
[['D', 'C', 'B', 'A'], [2, 3, 5, 4], [6, 7, 9, 8]]