[R] remove substring from each string vector component

[Marc Schwartz]

On Mar 16, 2010, at 9:50 AM, arnaud chozo wrote:

> Hi all,
> 
> I have a string vector like that: x=c("1\t\t", "2", "3\t\t\t")
> I need to remove all the occurrences of "\t", in order to obtain: x = "1"
> "2"   "3"
> 
> I'm trying to use the function substring2, and it works for each component,
> for example:
> substring2(x[1], "\t") =""
> gives x = "1"   "2"   " 3\t\t\t"
> 
> I'd like to apply this function to each component and I tried the following:
> 
> myfun = function(x, i) {
>  substring2(x[i], "\t") = ""
> }
> 
> lapply(x, myfun)
> 
> which gives x="" "" ""
> 
> I know that I'm wrong somewhere using lapply, but I can't fix it.
> 
> Thanks in advance,
> Arnaud Chozo


This is a place to use regular expressions with gsub():

x <- c("1\t\t", "2", "3\t\t\t")

> gsub("\\t", "", x)
[1] "1" "2" "3"

See ?regex and ?gsub

Note that you have to double the backslashes in the regex.

HTH,

Marc Schwartz