Removing all “H” within the strings, EXCEPT the ones including “CH”

问题

I am trying to remove all "H" within the strings, EXCEPT the ones including "CH" in the following example:

strings <- c("Cash","Wishes","Chain","Chip","Check")

I found that the code below remove only "H"

data<- gsub("H", "", strings)

回答1:

You can do this with a negative look-behind.

gsub("(?<!c)h", "", strings, perl=TRUE, ignore.case = TRUE)

来源：https://stackoverflow.com/questions/47538826/removing-all-h-within-the-strings-except-the-ones-including-ch