Hi: How about
> as.data.frame(with(df, table(group, level, color))) group level color Freq 1 A 1 blue 1 2 B 1 blue 1 3 A 2 blue 1 4 B 2 blue 2 5 A 1 Red 1 6 B 1 Red 0 7 A 2 Red 2 8 B 2 Red 2 where df is the name of the data frame. HTH, Dennis On Tue, May 11, 2010 at 5:38 PM, Noah Silverman <n...@smartmediacorp.com>wrote: > Hi, > > An example data set is: > > group level color > A 1 "blue" > A 1 "Red" > B 1 "blue" > B 2 "Red" > A 2 "Red" > B 2 "Red" > B 2 "blue" > B 2 "blue" > A 2 "blue" > A 2 "Red" > > > I'd like to compute a summary of counts for each combination of group, > level, color. > > An example output would be something like this: > group level color count > A 1 "blue" 1 > A 2 "red" 2 > B 2 "red" 2 > etc.. > > > The tapply function seems to do this for a single variable, but I can > figure out to to do it for combinations of more than one factor. I also see > the ave function, but can't figure out how to apply it to multiple factors. > > Any suggestions? > > Thanks > > > ______________________________________________ > 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. > [[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.
