Question

Mylists = [[＆＃39; A B＆＃39;，＆＃39; AB C＆＃39;，＆＃39; ABC D＆＃39;]，[＆＃39; C＆＃39;，＆＃ 39; DE F＆＃39;，＆＃39; A B＆＃39;]]

如何获得如下列表：myli = [[＆＃39; A＆＃39;，＆＃39; B＆＃39;，＆＃39; A＆＃39;＆＃39; B＆＃39; ＆＃39; C＆＃39;＆＃39; A＆＃39;＆＃39; B＆＃39;，＆＃39; C＆＃39;＆＃39; d＆＃39;]，[＆＃ 39; C＆＃39;＆＃39; d＆＃39;＆＃39; E＆＃39;＆＃39; F＆＃39;＆＃39; A＆＃39;＆＃39; B＆＃39 ;]]

这是我的代码：

x = []
myli = []

for item in Mylists:
    for i in range(len(item)):
        x.extend(item[i].split())
    myli.append(x)

Answer 1

你需要在外部forloop中初始化x。

您的代码

Mylists = [['A B','A B C','A B C D'],['C','D E F','A B']]
x = []
myli = []

for item in Mylists:
    for i in range(len(item)):
        # BUG: since x is not reinitialized, it contains the same old
        # memory address that was appended to myli
        # extending x means you are modifying the x that you previously appended to myli
        # infact, every appended x is the same x !
        x.extend(item[i].split())

    # appending the same old x, which will inevitably be modified
    # in the next iteration
    myli.append(x)

校正

Mylists = [['A B','A B C','A B C D'],['C','D E F','A B']]
myli = []

for item in Mylists:
    x = [] # reinitialize x
    for i in range(len(item)):
        x.extend(item[i].split())
    myli.append(x)

Answer 2

假设mylist是字符串列表的列表，其中单词用空格分隔：

ml = [['A B','A B C','A B C D'],['C','D E F','A B']]
l = []
for inner in ml:
    newinner = []
    for innerstr in inner:
       for word in innerstr.split(' ')
                newinner.append(word)
    l.append(newinner)

如何将列表列表附加到一个列表中

2 个答案: