Michael, this comment doesn't seem appropriate to the question, since the sample data is a ragged array that requires the addition of NAs to fit into a wide format. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity.
Michael Dewey <i...@aghmed.fsnet.co.uk> wrote: >At 08:56 17/11/2012, Kemi Racheal wrote: >>Dear list member, >> >>I have the following data example >>ke <- data.frame(patid=c(1,1,1,2,3,3),a=c(1,2,2,1,1,2)) >> >>I want to add another variable b, such that the max of 'a' by id is >returned >>i.e data ke becomes >>ke <- >data.frame(patid=c(1,1,1,2,3,3),a=c(1,2,2,1,1,2),b=c(2,2,2,1,2,2)) >> >>Any help will be appreciated. > >Dear Kemi >It is often easier to do some sorts of manipulations on the wide >format of the data. I appreciate that you can always do it both ways. > > >>Oluwakemi >> >> >> [[alternative HTML version deleted]] > >Michael Dewey >i...@aghmed.fsnet.co.uk >http://www.aghmed.fsnet.co.uk/home.html > >______________________________________________ >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.