regex - 使用 r 中的定界符数组拆分字符串

Question

我是 R 的新手。我必须根据短语定界符拆分句子。我们可以使用 strsplit 基于一个分隔符拆分字符串。我想根据分隔符的数量拆分字符串，例如 [, . : ; ].我怎样才能一步完成。有适用于此的正则表达式吗？

例如:

my_string = "This is a sentence.  This is a question, right?  Yes!  It is."

预期输出:

"This is a sentence", "This is a question", "right", "yes", "It is"

Answer 1

你可以使用这个:

strsplit("This is a sentence. This is a question, right? Yes! It is.", "\\.|,|\\?|!")
#[[1]]
#[1] "This is a sentence"  " This is a question" " right"             
#[4] " Yes"                " It is"

要去掉那些多余的空格，你可以这样做:

strsplit("This is a sentence. This is a question, right? Yes! It is.",
         "\\. *|, |\\? *|! *")
#[[1]]
#[1] "This is a sentence" "This is a question" "right"             
#[4] "Yes"                "It is"

正如 thelatemail 指出的，这更简单:

strsplit("This is a sentence. This is a question, right? Yes! It is.",
     "[,.:;?!]\\s*")  # \\s* represents a space character appearing 0 or more times

您需要对某些被解释为元字符的字符进行转义。这就是为什么您会在 . 和 ? 前面看到 \\。 | 是一种“或”。