From david.meyer at wu-wien.ac.at  Tue Aug 10 14:04:48 2004
From: david.meyer at wu-wien.ac.at (David Meyer)
Date: Tue Aug 10 14:04:52 2004
Subject: [Rd] plot(SOM) segfaults (PR#7157)
In-Reply-To: <Pine.LNX.4.44.0408101217300.8623-100000@gannet.stats>
References: <20040810104531.5929011195@slim.kubism.ku.dk>
	<Pine.LNX.4.44.0408101217300.8623-100000@gannet.stats>
Message-ID: <20040810140448.3d9f9d91.david.meyer@wu-wien.ac.at>

On Tue, 10 Aug 2004 12:22:19 +0100 (BST)
Prof Brian Ripley <ripley@stats.ox.ac.uk> wrote:

> It is reasonable to expect plot to work for any arbitrary function, or
> alternatively for any function to work with this sort of abuse?

I think the former, but I agree it is impossible to do the necessary
checks. 

What probably remains is to add some check in SOM() to avoid the
segfault.
(Which, I guess, occurs in the call of "VR_onlineSOM" because n =
as.integer(nrow(data)) becomes numeric(0) since nrow(data) is NULL in
this case?)

So, this bug report was indeed sent to the wrong place, my apologies...

-d

> 
> If the latter, this is a bug report on class and was sent to the wrong
> 
> place (see the FAQ).
> 
> If the former, plot.function and curve do no checking, but what could
> they reasonably do?
> 
> On Tue, 10 Aug 2004 david.meyer@wu-wien.ac.at wrote:
> 
> > 
> > library(class)
> > plot(SOM)
> > 
> > segfaults in curve() at the line:
> > 
> >  y <- eval(expr, envir = list(x = x), enclos = parent.frame())
> > 
> > at least since R version 1.8.1.
> > 
> > Version:
> >  platform = i686-pc-linux-gnu
> >  arch = i686
> >  os = linux-gnu
> >  system = i686, linux-gnu
> >  status = Under development (unstable)
> >  major = 2
> >  minor = 0.0
> >  year = 2004
> >  month = 07
> >  day = 27
> >  language = R
> > 
> > Search Path:
> >  .GlobalEnv, package:class, package:methods, package:stats,
> > package:graphics, package:utils, Autoloads, package:base
> > 
> > 
> 
> -- 
> 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
> 
> 


-- 
Dr. David Meyer
Department of Information Systems

Vienna University of Economics and Business Administration
Augasse 2-6, A-1090 Wien, Austria, Europe
Fax: +43-1-313 36x746 
Tel: +43-1-313 36x4393
HP:  http://wi.wu-wien.ac.at/Wer_sind_wir/meyer/


[Rd] plot(SOM) segfaults (PR#7157)
David Meyer