Extracting numbers from vectors of strings

Question

I have string like this:

years<-c(\"20 years old\", \"1 years old\")

I would like to grep only the numeric number from this vector. Expe

Answer 1

Here's an alternative to Arun's first solution, with a simpler Perl-like regular expression:

as.numeric(gsub("[^\\d]+", "", years, perl=TRUE))