Matlab：简单的正则表达式使用问题

如何解决Matlab：简单的正则表达式使用问题

我相信我有一个简单的问题。这是我想分割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.";

我想在这样的表格中划分以下数据（这是解决方案的外观）：

但是，我目前的解决方案是这样的：

因此第 1 行不正确，但第 2 行正确。否则，如果“CHAPTER #”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。这是生成此解决方案的代码：

[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。 （我怀疑将 if 语句与正确的 regexp 表达式结合使用。）

感谢所有帮助。

解决方法

你可以使用

>> 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.

  }
}

参见regex demo。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 - 要匹配的单词和空格
• \d+ - 一位或多位数字
• \s* - 零个或多个空格
• (.*?) - 捕获第 1 组：任何零个或多个字符，尽可能少
• (?:1|\z) - 1 或字符串结尾。