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

After the post from Gabor Grothendieck post at the r-help mailing list

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

library(gsubfn)
pat <- "[-+.e0-9]*\\d"
sapply(years, function(x) strapply(x, pat, as.numeric)[[1]])