Prof Ripley,

Thank you for your post. Below is the output of traceback(). I'm still not
sure what the problem is. Thank you.

4: as.matrix.data.frame(frame)
3: as.matrix(frame)
2: rpart.matrix(m)
1: rpart(lowergi ~ ., data=dset, method="class")



On 9/26/07, Prof Brian Ripley <ripley@stats.ox.ac.uk> wrote:
>
> On Wed, 26 Sep 2007, Juned Siddique wrote:
>
> > I'm using rpart to fit a tree using a large dataset: 7000 observations,
> 4651
> > variables. All but one of the variables (age) are binary. When I run the
> > code:
> >
> > fit1 <- rpart(lowergi ~ ., data=dset,method="class")
> >
> > I get the error:
> >
> >
> > Error in dimnames(X) <-list(dn[1L]], unlist(collabs, use.names=FALSE)) :
> > Length of `dimnames' [2] not equal to array extent
> >
> > I have no idea what this error means or what is causing the problem. I'm
> > wondering if my dataset is too big, or if there is a problem with how
> the
> > data are set up. Any help would be appreciated.
>
> Well, we would appreciate help from you, so please read the footer to this
> message.  All I can tell you is that the error message did not come from
> rpart, but most likely from as.matrix.data.frame (which does contain that
> code line, unlike rpart)
>
> The output of traceback() would have been helpful.  The `Writing R
> Extensions' manual shows you how to debug a problem like this.
>
> My best guess is that at least one of those 4651 columns are not suitable
> input to rpart.
>
> >
> >       [[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.
> >
>
> --
> Brian D. Ripley,                  ripley@stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>

	[[alternative HTML version deleted]]

