Here is another approach (I think this is the simplest): daylkp <- c(SAT=1, SUN=2, MON=3, TUE=4, WED=5, THU=6, FRI=7)
tmp.in <- sample( names(daylkp), 25, TRUE ) tmp.out <- daylkp[tmp.in] names(tmp.out) <- NULL # optional hope this helps, -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111 > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of Steve Matco > Sent: Friday, February 26, 2010 12:32 PM > To: r-help@r-project.org > Subject: [R] How to add a variable to a dataframe whose values are > conditional upon the values of an existing variable > > Hi everyone, > > I am at my wits end with what I believe would be considered simple by a > more experienced R user. I want to know how to add a variable to a > dataframe whose values are conditional on the values of an > existing variable. I can't seem to make an ifelse statement work for my > situation. The existing variable in my dataframe is a character > variable named DOW which contains abbreviated day names (SAT, SUN, > MON.....FRI). I want to add a numerical variable named DOW1 to my > dataframe that will take on the value 1 if DOW equals "SAT", 2 if DOW > equals "SUN", 3 if DOW equals "MON",.....,7 if DOW equals "FRI". > I know this must be a simple problem but I have searched everywhere > and tried everything I could think of. Any help would be greatly > appreciated. > > Thank you, > > Mike > > > > > ______________________________________________ > 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. ______________________________________________ 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.