You can do this: aggregate(iris[-5], iris[5], mean)
On 9/27/07, Mike Lawrence <[EMAIL PROTECTED]> wrote: > Hi all, > > A suggestion derived from discussions amongst a number of R users in > my research group: set the default column names produced by aggregate > () equal to the names of the objects in the list passed to the 'by' > object. > > ex. it is annoying to type > > with( > my.data > ,aggregate( > my.dv > ,list( > one.iv = one.iv > ,another.iv = another.iv > ,yet.another.iv = yet.another.iv > ) > ,some.function > ) > ) > > to yield a data frame with names = c > ('one.iv','another.iv','yet.another.iv','x') when this seems more > economical: > > with( > my.data > ,aggregate( > my.dv > ,list( > one.iv > ,another.iv > ,yet.another.iv > ) > ,some.function > ) > ) > > -- > Mike Lawrence > Graduate Student, Department of Psychology, Dalhousie University > > Website: http://memetic.ca > > Public calendar: http://icalx.com/public/informavore/Public > > "The road to wisdom? Well, it's plain and simple to express: > Err and err and err again, but less and less and less." > - Piet Hein > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel