使用gsub替换变量长度

Question

I have dataframe with 2 string

1) PWH+PTR

2) PWH++PTR

I want to write gsub function which replace any number of '+' exiting and gives you

1)PWH+PTR

2)PWH+PTR

I tried

l<-data.frame(gsub("\\+\\+","+",l[,1]), stringsAsFactors=FALSE)

does not work

Answer 1

您可以使用[+]+或\\\\++来匹配一个或多个+

l <- data.frame(gsub("[+]+","+", l[,1]), stringsAsFactors=FALSE)

Answer 2

Here is my solution with the regex quantifiers `+.

st <- c("PWH+PTR", "PWH++PTR")
 gsub("\\++", "\\+", st)
[1] "PWH+PTR" "PWH+PTR"