Removing special characters in the beginning of a word in R

问题

I am using the following code to remove the special characters from the begining of a word:

>gsub("^[^[:alnum:]]",'','#C++')
[1] "C++"

But If there are multiple special characters in the beggining it removes only the first one:

>gsub("^[^[:alnum:]]",'','$#C++')
[1] "#C++"

How can I make it to remove all the special characters in the begining so the output should be "C++"?

回答1:

We match one or more non-alpha numeric characters ([^[:alnum:]]+) from the beginning of the string (^) and replace it with ''.

 sub("^[^[:alnum:]]+",'','$#C++')

Or use

 sub("^\\W+",'','$#C++')
 #[1] "C++"

来源：https://stackoverflow.com/questions/34156898/removing-special-characters-in-the-beginning-of-a-word-in-r