Question

我正在尝试编写一个允许我接收文本的Python代码，并逐行读取。在每一行中，单词作为键进入字典，数字应该是指定的值，作为列表。文件'topics.txt'将由数百行具有相同格式的行组成：

1~cocoa
2~
3~
4~
5~grain~wheat~corn~barley~oat~sorghum
6~veg-oil~linseed~lin-oil~soy-oil~sun-oil~soybean~oilseed~corn~sunseed~grain~sorghum~wheat
7~
8~
9~earn
10~acq

等等.. 我需要为每个单词创建词典对于前：理想情况下，名称“grain”将是字典中的关键字，值将为dict [grain]：[5,6，..]。同样， “可可”将是另一个关键，价值观将是字典[可可]：[1，..] 不多，但到目前为止..

with open("topics.txt", "r") as fi:  # Data read from a text file is a string
    d = {}
    for i in fi.readlines():
        temp = i.split()
        #i am lost here
        num = temp[0]
        d[name] = [map(int, num)]

Answer 1

http://docs.python.org/3/library/collections.html#collections.defaultdict

import collections

with open('topics.txt') as f:
    d = collections.defaultdict(list)
    for line in f:
        value, *keys = line.strip().split('~')
        for key in filter(None, keys):
            d[key].append(value)

value, *keys = ...是Extended Iterable Unpacking，仅在Python 3.x中可用。

Answer 2

with open("topics.txt", "r") as file:  # Data read from a text file is a string
    dict = {}
    for fullLine in file:
        splitLine = fullLine.split("~")
        num = splitLine[0]
        for name in splitLine[1:]:
            if name in dict:
                dict[name] = dict[name] + (num,)
            else
                dict[name] = (num,)

如何从文件创建字典？

2 个答案: