Bart, I'm hardly one of the lists regex gurus: but this can get you started...
tests <- c("pH", "Assay (%)", "Impurity A(%)", "content (mg/ml)") x <- regexpr("\\((.*)\\)", tests) substr(tests, x + 1, x + attr(x, "match.length") - 2) Bart Joosen wrote:
Hi, this should be an easy one, but I can't figure it out. I have a vector of tests, with their units between brackets (if they have units). eg tests <- c("pH", "Assay (%)", "Impurity A(%)", "content (mg/ml)") Now I would like to hava a function where I use a test as input, and which returns the units like: f <- function (x) sub("\\)", "", sub("\\(", "",sub("[[:alnum:]]+","",x))) this should give "", "%", "%", "mg/ml", but it doesn't do the job quit well. After searching in the manual, and on the help lists, I cant find the answer. anyone? Bart
______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.