I think tapply does the job you want: tapply(C,B,mean,na.rm=TRUE) tapply(C,B,var,na.rm=TRUE)
Cheers, Daniel ------------------------- cuncta stricte discussurus ------------------------- -----Ursprüngliche Nachricht----- Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Im Auftrag von Agrarimmobilien Gesendet: Sunday, March 09, 2008 4:38 PM An: R-help@r-project.org Betreff: [R] transforming column of a dataframe by var- and median-functions Hello, I try to transform a data frame like A B C 1 1 2,5 2 2 NA 3 1 1,0 4 1 56 5 2 23 6 1 NA 7 2 46 to the following dataframe, calculating the variance and median of the C-column, group by B, so the result will be: B C(median) D (var) 1 19,83 9 2 34,5 21 Doing this, I got problems with the NAs in column C. I tried to combine the aggregate - function aggregate(C, list(B), FUN=(mean, var)) with the following functions var(C, use="complete.obs") median(C, rm.na=TRUE) but it doesn't work as I want. Has anybody an idea how to do this work? thank you Iksmax ______________________________________________ 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.
