如何通过从 .txt 文件中读取,为每个键创建具有多个“列表”的 Python 字典?

abo*_*emc 4 python dictionary

我有一个大文本文件,看起来像:

1   27  21  22
1   151 24  26
1   48  24  31
2   14  6   8
2   98  13  16
.
.
.
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我想用它创建一个字典。每个列表的第一个数字应该是字典中的键,并且应该采用以下格式:

{1: [(27,21,22),(151,24,26),(48,24,31)],
 2: [(14,6,8),(98,13,16)]}
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我有以下代码(总分是文本文件第一列中的最大数字(即字典中的最大键)):

from collections import defaultdict

info = defaultdict(list)
filetxt = 'file.txt'
i = 1

with open(filetxt, 'r') as file:
    for i in range(1, num_cities + 1):
        info[i] = 0
    for line in file:
        splitLine = line.split()
        if info[int(splitLine[0])] == 0:
            info[int(splitLine[0])] = ([",".join(splitLine[1:])])
        else:
            info[int(splitLine[0])].append((",".join(splitLine[1:])))
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哪个输出

{1: ['27,21,22','151,24,26','48,24,31'],
 2: ['14,6,8','98,13,16']}
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我想做这本字典的原因是因为我想对给定键的字典的每个“内部列表”运行 for 循环:

for first, second, third, in dictionary:
   ....
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由于字典的格式略有不同,我无法使用当前代码执行此操作(它在上面的 for 循环中需要 3 个值,但接收的值超过 3),但是它可以使用第一个字典格式。

任何人都可以建议解决这个问题吗?

the*_*eye 6

result = {}
with open(filetxt, 'r') as f:
    for line in f:
        # split the read line based on whitespace
        idx, c1, c2, c3 = line.split()

        # setdefault will set default value, if the key doesn't exist and
        # return the value corresponding to the key. In this case, it returns a list and
        # you append all the three values as a tuple to it
        result.setdefault(idx, []).append((int(c1), int(c2), int(c3)))
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编辑:由于您希望键也是整数,因此您可以在拆分值上使用mapint函数,如下所示

        idx, c1, c2, c3 = map(int, line.split())
        result.setdefault(idx, []).append((c1, c2, c3))
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  • `from collections import defaultdict` 然后`result = defaultdict(list)` 将只允许`result[idx].append(...)`,因为保证任何键都存在列表。 (4认同)