Extracting numbers from vectors of strings
How about
# pattern is by finding a set of numbers in the start and capturing themas.numeric(gsub("([0-9]+).*$", "\\1", years))or
# pattern is to just remove _years_oldas.numeric(gsub(" years old", "", years))or
# split by space, get the element in first indexas.numeric(sapply(strsplit(years, " "), "[[", 1))
I think that substitution is an indirect way of getting to the solution. If you want to retrieve all the numbers, I recommend gregexpr:
matches <- regmatches(years, gregexpr("[[:digit:]]+", years))as.numeric(unlist(matches))If you have multiple matches in a string, this will get all of them. If you're only interested in the first match, use regexpr instead of gregexpr and you can skip the unlist.