regex - Matlab：简单的正则表达式使用问题

Question

我相信我有一个简单的问题。这是我想划分的文学作品的数据样本：

WholeBook = "Random info - at beginning-man. "+ ...
        "Random info still continues. "+ ...
        "CHAPTER 1 " + ...
        "1 This is sentence one of verse one, "+ ...
        "This still sentence one of verse one. "+ ...
        "2 This is sentence one of verse two. "+ ...
        "This is sentence two of verse two. "+ ...
        "3 This is sentence one of verse three; "+ ...
        "this still sentence one of verse three. "+ ...
        "CHAPTER 2 " + ...
        "Random info in middle two. "+ ...
        "Random info still continues again. "+ ...
        "1 This is sentence four? "+ ...
        "2 This is sentence five, "+ ...
        "3 this still sentence five but verse three!"+ ...
        "Random info at end's end.";

我想在这样的表中划分以下数据（这就是解决方案的外观）：

但是，我当前的解决方案如下所示：

因此第 1 行是不正确的，但第 2 行是正确的。否则说，如果“第 # 章”之后确实有信息，我的解决方案有效，但如果没有信息，则无效。这是产生此解决方案的代码：

[tokens, RandomInfoMiddle] = regexp(WholeBook, '(CHAPTER \d)\s*(.*?)1', 'tokens', 'match');
RandomInfoMiddle = RandomInfoMiddle';
RandomInfoMiddle = regexprep(RandomInfoMiddle,'CHAPTER \d+ (.+) \d$','$1'); %Delete "Chapter+Nr" + ...1
            % To explain the regular expression (CHAPTER \d)\.\s*(.*?)1:
            % (CHAPTER \d) matches CHAPTER with any number, and the () brackets surrounding it will capture the match in the tokens variable.
            % \. matches the period
            % \s* matches any possible whitespace
            % (.*?)1 will capture any text till the next 1 in the text. Note the question mark to make it match lazy, otherwise it will match all the text till the last 1 in str.

请帮我找到第一张图片/表格中描述的解决方案。（我怀疑使用 if 语句加上正确的正则表达式。）

感谢所有帮助。

标签： regexmatlabif-statementdatatable

Answer 1

您可以使用

>> tokens = regexp(WholeBook, 'CHAPTER \d+\s*(.*?)(?:1|\z)', 'tokens', 'match');
>> tokens
tokens =
{
  [1,1] =
  {
    [1,1] =
  }

  [1,2] =
  {
    [1,1] = Random info in middle two.
Random info still continues again.

  }
}

请参阅正则表达式演示。注意不需要使用两个捕获组，您只需要一个。

正则表达式匹配：

• CHAPTER- 要匹配的单词，然后是空格
• \d+- 一位或多位数字
• \s*- 零个或多个空格
• (.*?)- 捕获组 1：任何零个或多个字符，尽可能少
• (?:1|\z)-1或字符串结尾。