From Torsten.Hothorn at rzmail.uni-erlangen.de  Mon Nov  7 09:20:32 2005
From: Torsten.Hothorn at rzmail.uni-erlangen.de (Torsten Hothorn)
Date: Mon, 7 Nov 2005 09:20:32 +0100 (CET)
Subject: [Rd] Classification Trees and basic Random Forest pkg using
	tree structures in C
In-Reply-To: <39B6DDB9048D0F4DAD42CB26AAFF0AFAFED569@usctmx1106.merck.com>
References: <39B6DDB9048D0F4DAD42CB26AAFF0AFAFED569@usctmx1106.merck.com>
Message-ID: <Pine.LNX.4.51.0511070917020.11505@artemis.imbe.med.uni-erlangen.de>


On Fri, 4 Nov 2005, Liaw, Andy wrote:
>
> For some of the data we encounter, all X variables are binary, so each data
> point can be encoded into a bitstring.  There are algorithms that take
> advantage of that.  The problem is interfacing such code with R.  I know of
> no good solutions.  As I told Grant, I thought about what he did, too, but
> the difficulty is how to pass such data structures to R.  Actually, some
> time down the road I might try to use the dendrogram class that's in R, and
> manipulate them in C.

I faced similar problems some time ago and ended up representing a
(binary) tree as recursive lists which can be manipulated from both the C
and R side. The `party' package has the code (and an internal random
forest function, however, without R interface yet) and the vignette
explains some details.

Best,

Torsten

> Not sure about efficiency though.
>
> Andy
>
>
> > Hin-Tak Leung
> >
> > ______________________________________________
> > R-devel at r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-devel
> >
> >
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
>



[Rd] Classification Trees and basic Random Forest pkg using tree structures in C
Torsten Hothorn