On Mon, Oct 24, 2011 at 5:39 AM, Duncan Murdoch <murdoch.dun...@gmail.com> wrote: > Suppose I have data like this: > > A <- sample(letters[1:3], 1000, replace=TRUE) > B <- sample(LETTERS[1:2], 1000, replace=TRUE) > x <- rnorm(1000) > > I can get a table of means via > > tapply(x, list(A, B), mean) > > and I can add the marginal means to this using cbind/rbind: > > main <- tapply(x, list(A,B), mean) > Amargin <- tapply(x, list(A), mean) > Bmargin <- tapply(x, list(B), mean) > > rbind(cbind(main, all=Amargin),all=c(Bmargin, mean(x))) > > But this is tedious. Has some package got some code that makes this easier?
Have a look at reshape2::add_margins - it's not super efficient, but I think cool because it works for arbitrarily many dimensions. Hadley -- Assistant Professor / Dobelman Family Junior Chair Department of Statistics / Rice University http://had.co.nz/ ______________________________________________ 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.
