Re: [Rd] Sweave processes \Sexpr in commented LaTeX source

From: Marc Schwartz (via MN) <>
Date: Thu 21 Sep 2006 - 16:15:13 GMT

On Thu, 2006-09-21 at 16:08 +0200, Jean lobry wrote:
> Marc,
> >I have a large .Rnw file and was in the process of doing some debugging.
> >I had set some R chunks to 'eval=false' in the process. This resulted in
> >some R objects not being created that were in turn used in the
> >subsequent \Sexpr's.
> I have often the same problem, I'm using a construct like :
> <<eval=F>>=
> x <- rnorm(100)
> @
> I have \Sexpr{ifelse(exists("x"), length(x), "???")} elements
> in vector x.
> This works well for me, and you have more control than a global
> \SweaveOpts{eval.Sexpr=false} would allow, for instance :
> <<TimeConsumingCodeChunk1,eval=F>>=
> x <- rnorm(100)
> ...
> @
> I have \Sexpr{ifelse(exists("x"), length(x), "Ooops, I forgot
> to evaluate TimeConsumingCodeChunk1")} elements in vector x.
> Wouldn't it be enough to mention this in Sweave's FAQ ?


Thanks for your comments and approach. I will keep it in mind.

In my case, I had a large flow/org type chart that I created with pstricks and there were quite a few Sexpr's in the chart code. All of the Sexpr's were based upon common objects created in preceding R chunks. I considered that it would be easier to simply treat it all as a common block that could be commented.

Based upon Fritz' reply today, it seems that we will have an easier solution coming.

Best regards,

Marc mailing list Received on Fri Sep 22 04:29:08 2006

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Thu 21 Sep 2006 - 19:30:13 GMT.

Mailing list information is available at Please read the posting guide before posting to the list.