如何从R中的字符串中删除一定长度的数字模式

发布于05月17日

说我有绳子-

some_string <- "this is a string with some numbers 9639998 21057535 1000 2021 2022"

我想删除7个字符长、8个字符长和4个字符长的数字模式，除非是1000.所以基本上我想要以下结果-

"this is a string with some numbers 1000"

推荐答案

这里使用gsub和正则表达式模式\b(?:\d{7,8}|(?!1000\b)\d{4})\b:

some_string <- "this is a string with some numbers 9639998 21057535 1000 2021 2022"
output <- gsub("\\b(?:\\d{7,8}|(?!1000\\b)\\d{4})\\b", "", some_string, perl=TRUE)
output

[1] "this is a string with some numbers   1000  "

实际上，更好的版本是这样的，它可以清理松散的空白:

some_string <- "this is a string with some numbers 9639998 21057535 1000 2021 2022"
output <- gsub("\\s*(?:\\d{7,8}|(?!1000\\b)\\d{4})\\s*", " ", some_string, perl=TRUE)
output <- gsub("^\\s+|\\s+$", "", gsub("\\s{2,}", " ", output))
output

[1] "this is a string with some numbers 1000"