Nick, On 13 May 2011 at 15:02, Nick Sabbe wrote: | Hello all. | | Today, I posted a question on stackoverflow.com, but I was advised to ask the | question through this mailing list.
That is indeed frequently suggested by Romain and myself, and I am glad that others suggested it to you to. With that, thanks for posting here. | | So, here is the verbatim question from SO (http://stackoverflow.com/questions/ | 5991314/basic-documentation-for-rcpp): I took a few minutes and quickly edited a reply over there. I will repost it here later if nobody beats me to answering your questions. Below are just some additional real quick answer. I really suggest that you make an effort of re-reading Rcpp-introduction which answers some of the questions below., | I want to look into rcpp to improve the speed of some of my R code without | having to resort to messy C++ code (I've had some success with that, but it | looks like code from hell). | | So, I checked the documentation provided with Rcpp, and also the bundle of | documents provided at Dirk Eddelbuettel's site. I installed and looked at | RcppExamples, but (at least from its documentation) most of these refer to | RcppClassic?. Besides that, I did some googling but that didn't result in | answers to what seem like basic questions. | | ? Do indexes in Rcpp work zero-based or one-based Zero-based as are all C and C++ programs (unless you do something crazy and redefine things). We do not attempt to change C++. | ? List provides both operator() and operator[], but apparently | not operator[[]]. It is not clear which ones are similar to [] and [[]] in R. There cannot be. We are bound by what C++ lets us do. Likewise there is no matrix indexing M[i][j] -- it has to be M(i,j). | ? Is there any support for factors in Rcpp (there does not appear to be | any)? It is on the TODO list but low priority for us. Export the factor levels as character, and the factor values via as.integer. Contributions of a Rcpp::Factor class would welcome. Dirk | Note: in fact I found some answers from the first example in | Rcpp-introduction.pdf, but that just felt like luck. | | Also, my stl is very rusty, so if anybody can provide me with a simple example | where each element of a List is (e.g.) print-ed with an stl-style loop, that | would be neat. | | If anybody wants to call me an idiot for not finding this information: go ahead | and make your day. Then make mine and point me to the docs I need :-) | | As a suggestions to Mr. Eddelbuettel and other Rcpp authors (I expect some of | them to read this): the class hierarchies and the like, provided by doxygen, | are really neat when you are already kneedeep into Rcpp, but for a beginner (in | Rcpp), I am more interested in a list of 'this method in this class does this | like that function in R' rather than 'you can find the declaration of this | operator in this header file'. After all, I understand one of the goals of Rcpp | is to lower the threshold for using C++ in R? Note: from what I have seen and | understood, I highly value the actual code of Rcpp and have the highest respect | for its creators. If the lack of basic documentation is merely a result of | 'lack of resources', I would be willing to become a resource (e.g.: work on | 'basic' documentation once I get through it myself). | | | | | | Nick Sabbe | | -- | | ping: [email protected] | | link: http://biomath.ugent.be | | wink: A1.056, Coupure Links 653, 9000 Gent | | ring: 09/264.59.36 | | | | -- Do Not Disapprove | | | | | ---------------------------------------------------------------------- | _______________________________________________ | Rcpp-devel mailing list | [email protected] | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel -- Gauss once played himself in a zero-sum game and won $50. -- #11 at http://www.gaussfacts.com _______________________________________________ Rcpp-devel mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
