From luke at stat.uiowa.edu  Tue Jan 25 21:09:50 2005
From: luke at stat.uiowa.edu (Luke Tierney)
Date: Tue Jan 25 21:10:01 2005
Subject: [Rd] Very Long Expressions
In-Reply-To: <Pine.A41.4.61b.0501240835500.41726@homer03.u.washington.edu>
References: <67DCA285A2D7754280D3B8E88EB5480206741E31@MSGBOSCLB2WIN.DMN1.FMR.COM>
	<Pine.LNX.4.61.0501241554410.3211@gannet.stats>
	<Pine.A41.4.61b.0501240835500.41726@homer03.u.washington.edu>
Message-ID: <Pine.LNX.4.58.0501251407150.13053@nokomis.stat.uiowa.edu>

On Mon, 24 Jan 2005, Thomas Lumley wrote:

> On Mon, 24 Jan 2005, Prof Brian Ripley wrote:
> 
> > On Mon, 24 Jan 2005, McGehee, Robert wrote:
> >
> > [Instructions to the R developers deleted.]
> >
> >> Secondly, the ?options help (thanks for everyone who reminded me about
> >> this), says that expressions can have values between 25...100000.
> >> 
> >> However, if the original example is set past 4995 on my computers, I
> >> receive a stack overflow.
> >
> > More accurately, you caused a protection stack overflow.
> >
> 
> At one point we were concerned about overflowing the C stack if 
> options(expressions=) were set too high.  I think this was in the days 
> when MacOS had a very small stack, and that things are safer now.
> 
> 
>  	-thomas

I hadn't noticed that they finally kicked the default up to 8M--good.

We still need to be a bit careful since running out of C stack will
cause a protection violation and there is no portabmle way to catch
this.  But we can probably afford to loosen the defaults a bit.

luke

-- 
Luke Tierney
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
   Actuarial Science
241 Schaeffer Hall                  email:      luke@stat.uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu


[Rd] Very Long Expressions
Luke Tierney