for example: > d = data.frame(gender=c("m","f","unkown"), x=rnorm(300)) > tapply(d$x,d$gender,mean) f m unkown 0.0787628409 0.0940534765 -0.0005323276
regards, stefan On Wed, Dec 09, 2009 at 04:50:37PM -0800, dolar wrote: > > Hi there > > I have a dataframe of a whole lot of variables > > lets say, one of my variables is gender > how do I simply get an average of all other variables by gender? > -- > View this message in context: > http://n4.nabble.com/simple-data-manipulation-question-tp956600p956600.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.