Hello, I used the aggregate function with success on my data frame "all".
> aggregate(all, list(sc_recov), mean) I then made a subset of this data frame: >s.all <-subset(all, select= c(3,4,5,6,7,8,9,10,11,23)) but when I tried to to run the aggregate function on this subset: > aggregate(s.all, list(sc_recov), mean) The result is garbage (i.e. its not grouping the data). So then I took my "all.csv", removed the unwanted columns and imported it into R as "small". > aggregate(small, list(sc_recov), mean) Error in FUN(X[[1L]], ...) : arguments must have same length Any thoughts? Thank you kindly, M Just [[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.