Re: [Rd] Aggregate factor names

From: Gabor Grothendieck <ggrothendieck_at_gmail.com>
Date: Thu, 27 Sep 2007 12:51:45 -0400

You can do this too:

aggregate(iris[-5], iris["Species"], mean)

or this:

with(iris, aggregate(iris[-5], data.frame(Species), mean))

or this:

attach(iris)
aggregate(iris[-5], data.frame(Species), mean)

The point is that you already don't have to write x = x. The only reason you are writing it that way is that you are using list instead of data.frame. Just use data.frame or appropriate indexing as shown.

On 9/27/07, Mike Lawrence <Mike.Lawrence_at_dal.ca> wrote:
> Understood, but my point is that the naming I suggest should be the
> default. One should not be 'punished' for being explicit in calling
> aggregate.
>
>
> On 27-Sep-07, at 1:06 PM, Gabor Grothendieck wrote:
>
> > You can do this:
> >
> > aggregate(iris[-5], iris[5], mean)
> >
> >
> > On 9/27/07, Mike Lawrence <Mike.Lawrence_at_dal.ca> 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_at_r-project.org mailing list
> >> https://stat.ethz.ch/mailman/listinfo/r-devel
> >>
>
> --
> 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
>
>
>



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https://stat.ethz.ch/mailman/listinfo/r-devel Received on Thu 27 Sep 2007 - 16:54:25 GMT

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