Have a look at table table(na.omit(dta)$grp)
Untested! ------------------------------------------------------------------------ ---- ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek team Biometrie & Kwaliteitszorg Gaverstraat 4 9500 Geraardsbergen Belgium Research Institute for Nature and Forest team Biometrics & Quality Assurance Gaverstraat 4 9500 Geraardsbergen Belgium tel. + 32 54/436 185 thierry.onkel...@inbo.be www.inbo.be To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of. ~ Sir Ronald Aylmer Fisher The plural of anecdote is not data. ~ Roger Brinner The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. ~ John Tukey > -----Oorspronkelijk bericht----- > Van: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] Namens Marcus Drescher > Verzonden: vrijdag 8 oktober 2010 16:29 > Aan: r-help@r-project.org > Onderwerp: [R] Count values in a dataframe with respect to groups > > Dear all, > > I am looking for a function to count values belonging to a > class within a dataframe (and ignore NAs). > > grp = c(1,1,1, 1,2, 2,2) > val = c(2,1,5,NA,3,NA,1) > > dta = data.frame(grp=grp, val=val) > > The result should look like: > > grp count > 1 3 > 2 2 > > At the moment, I am trying to find a function for FUN in > aggregate, but with no success. Can anybody help me? > > Thanks in advance. > Marcus > > ______________________________________________ > 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.