如何通过阻止嵌套列表中的单词来获取嵌套列表?

How to get a nested list by stemming the words inside the nested lists?

我有一个 Python 列表,其中有几个子列表的标记为 tokens。 我想阻止其中的标记,以便输出为 stemmed_expected.

tokens = [['cooked', 'lovely','baked'],['hotel', 'going','liked'],['room','looking']]

stemmed_expected: [['cook', 'love','bake'],['hotel', 'go','like'],['room','look']]

我试过的for循环如下:

from nltk.stem import PorterStemmer  
ps = PorterStemmer()

stemmed_actual = []

for m in tokens:
    for word in m:
        word = ps.stem(word)
        stemmed_actual.append(word)

但是这个for循环的输出是:

stemmed_actual = ['cook', 'love', 'bake', 'hotel', 'go', 'like', 'room', 'look']

如何修改 for 循环以获取子列表中的词干词,就像在 stemmed_expected 中一样?

您可以使用嵌套列表理解:

from nltk.stem import PorterStemmer

tokens = [['cooked', 'lovely','baked'],['hotel', 'going','liked'],['room','looking']]

ps = PorterStemmer()
stemmed = [[ps.stem(word) for word in sublst] for sublst in tokens]

print(stemmed)
# [['cook', 'love', 'bake'], ['hotel', 'go', 'like'], ['room', 'look']]