Hi [EMAIL PROTECTED] napsal dne 07.12.2007 10:04:35:
> Hello, > > I have a dataframe of say 20 lines with one line per individual. I want to > group these 20 individuals > by length class (eg. of 5cm) and get the mean value of all the other variables > (eg VarA and VarB) for each length class > > My dataframe is as follow: > > Length <- 10:30 > VarA <- seq(1000,1200,10) > VarB <- seq(500,700,10) > Data <- cbind(Length,VarA,VarB) > > > And I want to get something like: > > > Length Class Mean VarA Mean VarB > [10-15[ 1020 520 > [15-20[ 1070 570 > [20-25[ 1120 620 > [25-30] 1175 675 > > > Would you have any suggestions how to do that ? > Many thanks. Cut and aggregate fac <- cut(Data[,1], seq(5,30,5)) > aggregate(Data[,-1],list(fac), mean) Group.1 VarA VarB 1 (5,10] 1000 500 2 (10,15] 1030 530 3 (15,20] 1080 580 4 (20,25] 1130 630 5 (25,30] 1180 680 is close, but you need to add first level in fac into the second. lev<-levels(fac) levels(fac)<-lev[c(2,2,3,4,5)] > aggregate(Data[,-1],list(fac), mean) Group.1 VarA VarB 1 (10,15] 1025 525 2 (15,20] 1080 580 3 (20,25] 1130 630 4 (25,30] 1180 680 Not sure if it is the most elegant solution but it works. Regards Petr > > > Sonia. > > [[alternative HTML version deleted]] > > ______________________________________________ > 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.
