Dear all, The Walker Alias method is now (finally) implemented, along with unit tests. To my knowledge, the only thing not implemented is R's sample2 - a special version of sample.int for (!replace && is.null(prob) && n > 1e+07 && size <= n/2).
I also added rmultinom, which behaves how an R API C function call might, providing a single draw. E.g., in R, rmultinom(1, size, prob). It's the user's responsibility to normalize probabilities with the provided function Fixup, which I moved from sample.h to a separate file, fixup.h. rmultinom does throw a range_error in probs don't sum to ~1. Pull request is here: https://github.com/RcppCore/RcppArmadillo/pull/22 Best, Christian On Thu, Mar 28, 2013 at 11:18 PM, Christian Gunning <x...@unm.edu> wrote: > Dirk, > > See attached for minor edits related to Walker Alias method. Based on > the timing tests from the gallery draft and discussion with Johnathan, > we decided it was a bad idea to include code that deviates from R's > behavior, and is slower than R to boot. Thus, the C++ sample now > throws an informative error under the appropriate conditions. I > updated the unitTests accordingly (and cleaned them up a bit). > > Incidentally, there's now a stub in place for Walker Alias method > sample function, as well as an associated unitTest that's now > commented out. > -Christian -- A man, a plan, a cat, a ham, a yak, a yam, a hat, a canal – Panama! _______________________________________________ Rcpp-devel mailing list Rcpp-devel@lists.r-forge.r-project.org https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
