Question

我尝试做一个正则表达式，它包括在人称代词和'？'之间获取特定单词的长度。与findall。我做了一些研究，但没有找到如何检查一个字符串是否以......开头并以...结束......是否有类似的东西？

编辑：这是一个例子：我有一篇很长的文字，我想知道“疯狂”一词多少次被问到这样一个问题：

Are you crazy ? -> match because there a personal pronouns AND a '?' between the word
you are crazy ? -> No, because the word is between a verb and a '?'
Is he crazy ? -> match because there a personal pronouns AND a '?' between the word

Answer 1

你所追求的目标似乎比正则表达更加复杂，但是这里可以提供帮助：

import re

word_to_match="crazy"
pattern = "[^\\.\\?]*\\s(he|she|you|it|they|I)\\s({})\\s?\\?".format(word_to_match)


print (re.findall(pattern, "Are you crazy? You are crazy? Is he crazy?"))

Answer 2

如果你不想匹配＆＃34;你疯了吗？＆＃34;那应该可以解决问题。形式：

>>> import re
>>> pat = '(?:I|you|he|she|it|we|they|me|him|her|it|us|them) (?:an? )?(\w\w+)\s?\?'
>>> re.findall(pat, "is he available ? Isn't she a jerk ?")
['available', 'jerk']

否则，这可能有效：

>>> import re
>>> pat = '(?:I|you|he|she|it|we|they|me|him|her|it|us|them)((?: [a-z]+)+)\s?\?'
>>> filt = re.findall(pat, "is he available ? Isn't she a jerk ? you are crazy ?")
>>> filt
[' available', ' a jerk', ' are crazy']
#Then to get the number of times crazy appeared in a question :
>>> len([el for el in filt if "crazy" in el])
1

对于第二种方法，你实际上做了两个过滤器，一个用于提取人称代词和＆＃34;？＆＃34;之间的所有内容。然后，您再次过滤以计算目标词在这些问题表单中的次数。但是对于后者来说，一个更有效的方法是使用另一个正则表达式，因为我的实际肮脏的方式将计算＆＃34; notsocrazy＆＃34;作为比赛

如果包围Python正则表达式匹配

2 个答案: