[R] ifelse and wildcard matching

[Duncan Murdoch]

On 06/12/2009 3:05 PM, Jennifer Brea wrote:
> Hi,
> 
> I'm trying to create a new variable using the following code:
> 
> A$B2<-ifelse(A$B %in% "EDUCATION","EDUCATION",NA)
> 
> The problem is, I want the new variable to be labeled "EDUCATION" if the 
> original *contains* "EDUCATION", not of it is an exact match.  I've done 
> a lot of searching on wild cards and the like, and the only function 
> I've found that does this kind of matching is grep(), which I don't 
> think I can use here, since it subsets the original data.

grepl() is probably easiest:

A$B2 <- A$B
A$B2[ !grepl("EDUCATION", A$B2) ] <- NA

Duncan Murdoch