python - 如何将文本文件中的某些单词大写？

Question

我有一个包含正常句子的文本文件。实际上，我在输入该文件时很着急，所以我只是将句子第一个单词的第一个字母大写（根据英语语法）。

但是现在我希望每个单词的第一个字母都大写会更好。就像是：

这句话的每个单词都大写

上面句子中要注意的一点是of和is不是大写的，实际上我想转义等于或小于3个字母的单词。

我该怎么办？

Answer 1

for line in text_file:
    print ' '.join(word.title() if len(word) > 3 else word for word in line.split())

编辑：省略计数标点符号替换len为以下功能：

def letterlen(s):
    return sum(c.isalpha() for c in s)

Answer 2

看看NLTK。

标记每个单词，并大写。诸如“if”、“of”之类的词称为“停用词”。如果您的标准仅仅是长度，史蒂文的回答是这样做的好方法。如果您想查找停用词，SO 中有一个类似的问题：How to remove stop words using nltk or python。

Answer 3

您应该拆分单词，并且只将那些超过三个字母的单词大写。

words.txt：

each word of this sentence is capitalized
some more words
an other line

-

import string


with open('words.txt') as file:
    # List to store the capitalised lines.
    lines = []
    for line in file:
        # Split words by spaces.
        words = line.split(' ')
        for i, word in enumerate(words):
            if len(word.strip(string.punctuation + string.whitespace)) > 3:
                # Capitalise and replace words longer than 3 (without punctuation).
                words[i] = word.capitalize()
        # Join the capitalised words with spaces.
        lines.append(' '.join(words))
    # Join the capitalised lines.
    capitalised = ''.join(lines)

# Optionally, write the capitalised words back to the file.
with open('words.txt', 'w') as file:
    file.write(capitalised)

Answer 4

你真正想要的是一个叫做停用词列表的东西。如果没有此列表，您可以自己构建一个并执行以下操作：

skipWords = set("of is".split())
punctuation = '.,<>{}][()\'"/\\?!@#$%^&*' # and any other punctuation that you want to strip out
answer = ""

with open('filepath') as f:
    for line in f:
        for word in line.split():
            for p in punctuation:
                # you end up losing the punctuation in the outpt. But this is easy to fix if you really care about it
                word = word.replace(p, '')  
            if word not in skipwords:
                answer += word.title() + " "
            else:
                answer += word + " "
    return answer # or you can write it to file continuously

Answer 5

您可以将文本文件中的所有元素添加到列表中：

list = []
f.open('textdocument'.txt)
for elm in f (or text document, I\'m too tired):
   list.append(elm)

一旦你有一个列表中的所有元素，运行一个 for 循环来检查每个元素的长度，如果它大于三个，则返回第一个大写的元素

new_list = []
for items in list:
   if len(item) > 3:
      item.title()    (might wanna check if this works in this case)
      new_list.append(item)
   else:
   new_list.append(item)    #doesn't change words smaller than three words, just adds them to the new list

看看这是否有效？