Return 如果单词列表中的每个单词都存在于以单词列表作为值的字典中，则为键

Question

我有一个独特的用例。我的主要要求是效率和速度。我有一个长度为 40,000 的单词列表和一个格式为 data: {id1: ['hi','how'],id2:['I','love]..} 且长度为 250,000 的字典。我已经在这里解决了很多关于 SO 的问题，但找不到一个可能有效的问题。

如何检查单词列表中的每个单词是否存在于每个词典的单词列表（值）中？通常，可以执行以下操作：

all_words = get_vocabulary(data)
index = {}
for word in all_words:
    for doc, tokens in data.items():
        if word in tokens :
            ''' do something with key and tokens'''

通过这样做，我可以检查单词是否存在并完成其余的工作。但是，我的字典和列表很大，这需要很长时间。

If I have to go over a dictionary over and over again, it clearly marks a problem as mentioned by @DeepSpace in this question

非常感谢您提供的任何帮助。

Answer 1

您可以从字典中创建索引以加快搜索速度。例如：

all_words = ["word1", "word2"]

dct = {
    "id1": ["tis", "word1", "and", "word2"],
    "id2": ["word3", "word4"],
    "id3": ["word2", "only"],
}

# create index dictionary:
index_dct = {}
for k, v in dct.items():
    for word in v:
        index_dct.setdefault(word, []).append(k)

# index dictionary is:
# {
#     "tis": ["id1"],
#     "word1": ["id1"],
#     "and": ["id1"],
#     "word2": ["id1", "id3"],
#     "word3": ["id2"],
#     "word4": ["id2"],
#     "only": ["id3"],
# }


# now the search:
for word in all_words:
    if word in index_dct:
        for doc in index_dct[word]:
            print("Word: {} Doc: {} Tokens: {}".format(word, doc, dct[doc]))

打印：

Word: word1 Doc: id1 Tokens: ['tis', 'word1', 'and', 'word2']
Word: word2 Doc: id1 Tokens: ['tis', 'word1', 'and', 'word2']
Word: word2 Doc: id3 Tokens: ['word2', 'only']

Return 如果单词列表中的每个单词都存在于以单词列表作为值的字典中，则为键

Return the key if the each word in a list of words exists in a dictionary having a list of words as value

python

dictionary

for-loop

list-comprehension

list