Hello all, I need to count the number of times certain characters occur in a string. The only way I have found so far to accomplish this is by using strsplit i.e. my.string <- "DDDRRHIH" my.char <- "D" num.char <- -1 + length(unlist(strsplit(my.string,my.char))) now you probably won't be surprised if I say that this has proven to be extremely slow (I am not sure exactly why though, is it because strsplit creates new list for every call?). Is there an alternative way to do this short of going to compiled code? many thanks, -- Murad Nayal M.D. Ph.D. Department of Biochemistry and Molecular Biophysics College of Physicians and Surgeons of Columbia University 630 West 168th Street. New York, NY 10032 Tel: 212-305-6884 Fax: 212-305-6926