Re: [R] Contributing to the R Extensions documentation
> "Ross" == Ross Boylan <[EMAIL PROTECTED]> > on Wed, 05 Nov 2003 12:31:28 -0800 writes: Ross> On Wed, 2003-11-05 at 12:06, Prof Brian Ripley wrote: >> A list is just a vector of type VECSXP. There IS a >> section called `Handling lists'. >> >> I don't think the gap is in the `Writing R Extensions' >> document, maybe in your reading of it. >> Ross> That section discusses reading lists, not making them. Ross> It also includes no explicit statement that the names Ross> of list items are in the R_NamesSymbol attribute, nor Ross> instructions on how to create the value that goes in Ross> that attribute (i.e., it should be a character vector Ross> and its elements made with mkChar()). (I'm also not Ross> sure how deep one needs to use PROTECT, though that's Ross> a more general issue.) Ross> There is no explicit statement that the elements of Ross> the list are arbitrary SEXP's. Ross> I also had the list[i] vs list[[i]] lurking in my Ross> mind, wondering how that mapped to the C level Ross> constructs. That is less central. Ross> I'm not saying the clues aren't there; after all, I Ross> did work it out, I think correctly. I am saying that Ross> certain information would be better stated explicitly Ross> rather than simply being open to inference from an Ross> example. And I am saying that an explicit example of Ross> constructing and returning a list (with named members) Ross> would be useful, since that's a common scenario. I tend to agree. I assume most people will read that manual electronically --- as opposed to "on paper", because you can search quickly --- and such a proposed addition would be quite helpful. Alternatively, and sometimes even more usefully, one could consider providing these more extended examples as files (*.c, *.R, Makefile, .. or even better, as an R package (with a vignette !) which would have an almost purely didactical aim. As an R package --- source only, no binaries! --- it had the advantage of providing "provably" (via R CMD check) working code. Martin Maechler <[EMAIL PROTECTED]> http://stat.ethz.ch/~maechler/ Seminar fuer Statistik, ETH-Zentrum LEO C16Leonhardstr. 27 ETH (Federal Inst. Technology) 8092 Zurich SWITZERLAND phone: x-41-1-632-3408 fax: ...-1228 <>< >> On Wed, 5 Nov 2003, Ross Boylan wrote: >> >> I thought there were some gaps in the R Extensions >> document; in particular, I was left wondering how to >> create a list. I think a paragraph on it would be >> useful. >> >> I would be happy to contribute the paragraph, but I'm >> not sure if there's interest or what the procedure is. >> Can anyone advise me? >> >> Though I was looking at the 1.7.0 version, I just >> checked 1.8.0 and the relevant section seems the same. >> >> My ulterior motive is to discover if my understanding >> of lists is actually correct :) __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
Re: [R] Contributing to the R Extensions documentation
On Wed, 2003-11-05 at 12:06, Prof Brian Ripley wrote: > A list is just a vector of type VECSXP. > There IS a section called `Handling lists'. > > I don't think the gap is in the `Writing R Extensions' document, maybe in > your reading of it. > That section discusses reading lists, not making them. It also includes no explicit statement that the names of list items are in the R_NamesSymbol attribute, nor instructions on how to create the value that goes in that attribute (i.e., it should be a character vector and its elements made with mkChar()). (I'm also not sure how deep one needs to use PROTECT, though that's a more general issue.) There is no explicit statement that the elements of the list are arbitrary SEXP's. I also had the list[i] vs list[[i]] lurking in my mind, wondering how that mapped to the C level constructs. That is less central. I'm not saying the clues aren't there; after all, I did work it out, I think correctly. I am saying that certain information would be better stated explicitly rather than simply being open to inference from an example. And I am saying that an explicit example of constructing and returning a list (with named members) would be useful, since that's a common scenario. > On Wed, 5 Nov 2003, Ross Boylan wrote: > > > I thought there were some gaps in the R Extensions document; in > > particular, I was left wondering how to create a list. I think a > > paragraph on it would be useful. > > > > I would be happy to contribute the paragraph, but I'm not sure if > > there's interest or what the procedure is. Can anyone advise me? > > > > Though I was looking at the 1.7.0 version, I just checked 1.8.0 and the > > relevant section seems the same. > > > > My ulterior motive is to discover if my understanding of lists is > > actually correct :) > > -- Ross Boylan wk: (415) 502-4031 530 Parnassus Avenue (Library) rm 115-4 [EMAIL PROTECTED] Dept of Epidemiology and Biostatistics fax: (415) 476-9856 University of California, San Francisco San Francisco, CA 94143-0840 hm: (415) 550-1062 __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
Re: [R] Contributing to the R Extensions documentation
A list is just a vector of type VECSXP. There IS a section called `Handling lists'. I don't think the gap is in the `Writing R Extensions' document, maybe in your reading of it. On Wed, 5 Nov 2003, Ross Boylan wrote: > I thought there were some gaps in the R Extensions document; in > particular, I was left wondering how to create a list. I think a > paragraph on it would be useful. > > I would be happy to contribute the paragraph, but I'm not sure if > there's interest or what the procedure is. Can anyone advise me? > > Though I was looking at the 1.7.0 version, I just checked 1.8.0 and the > relevant section seems the same. > > My ulterior motive is to discover if my understanding of lists is > actually correct :) > -- Brian D. Ripley, [EMAIL PROTECTED] 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, UKFax: +44 1865 272595 __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
[R] Contributing to the R Extensions documentation
I thought there were some gaps in the R Extensions document; in particular, I was left wondering how to create a list. I think a paragraph on it would be useful. I would be happy to contribute the paragraph, but I'm not sure if there's interest or what the procedure is. Can anyone advise me? Though I was looking at the 1.7.0 version, I just checked 1.8.0 and the relevant section seems the same. My ulterior motive is to discover if my understanding of lists is actually correct :) -- Ross Boylan wk: (415) 502-4031 530 Parnassus Avenue (Library) rm 115-4 [EMAIL PROTECTED] Dept of Epidemiology and Biostatistics fax: (415) 476-9856 University of California, San Francisco San Francisco, CA 94143-0840 hm: (415) 550-1062 __ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
