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[Rcpp-devel] Rcpp equivalent of sample()?

2 messages · Douglas Bates, Dirk Eddelbuettel

Douglas Bates
# 
You can check what is done in R itself in the R sources but I imagine that
it uses a uniform random variate converted to an integer through the
cumulative probabilities. The good news is that it is easy to create the
cumulative weights with the std::accumulate function.
On May 14, 2011 4:12 PM, "Chris DuBois" <chris.dubois at gmail.com> wrote:
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Dirk Eddelbuettel
#
On 14 May 2011 at 16:33, Douglas Bates wrote:
| You can check what is done in R itself in the R sources but I imagine that it
| uses a uniform random variate converted to an integer through the cumulative
| probabilities. The good news is that it is easy to create the cumulative
| weights with the std::accumulate function.

Good point. I just looked at src/main/random.c in the R sources, and the main
worker functions are once again defined as hidden.  Sigh.  May make sense to
'port' this as helper functions for Rcpp::IntegerVector.

Dirk