python 3.X中的过滤器对象[重复]

Question

在 python 3.X 中，我一直在编写这些代码：

一个函数用于“text_tokenizing”，另一个函数用于“删除多余字符”。 在“remove_characters_after_tokenization”函数中，我使用了“filter”。

我的问题：当我运行我的项目时，我在控制台中看到这一行：

<filter object at 0x00000277AA20DE48> <filter object at 0x00000277AA44D160> <filter object at 0x00000277AA44D470>

我该如何解决这个问题？

这是我项目的代码：

import nltk
import re
import string
from pprint import pprint

corpus = ["The brown fox wasn't that quick and he couldn't win the race",
          "Hey that's a great deal! I just bought a phone for $199",
          "@@You'll (learn) a **lot** in the book. Python is an amazing language !@@"]



# Declare a function for "Tokenizing Text"
def tokenize_text(text):
    sentences = nltk.sent_tokenize(text)
    word_tokens = [ nltk.word_tokenize(sentence) for sentence in sentences]
    return word_tokens

# Declare a function for "Removing Special Characters"
def remove_characters_after_tokenization(tokens):
    pattern = re.compile('[{}]'.format(re.escape(string.punctuation)))
    filtered_tokens = list(filter(None, [pattern.sub('', token) for token in tokens]))
    return filtered_tokens


token_list = [tokenize_text(text) for text in corpus]
pprint(token_list)

filtered_list_1 = list(filter(None,[remove_characters_after_tokenization(tokens)
                                for tokens in sentence_tokens])
                   for sentence_tokens in token_list)

print(type(filtered_list_1))
print(len(filtered_list_1))
print(filtered_list_1)

Answer 1

以下行为每个 sentence_tokens 在 token_list:

filtered_list_1 = list(filter(None, [remove_characters_after_tokenization(tokens)
                                for tokens in sentence_tokens])
                   for sentence_tokens in token_list)

也许您想创建一个列表列表：

filtered_list_1 = list(filter(None, ([remove_characters_after_tokenization(tokens)
                                      for tokens in sentence_tokens]
                                     for sentence_tokens in token_list)))