This would be easier if base::set.seed() accepted a value of .Random.seed instead of just a scalar integer or, new to R-3.0.0, NULL. If set.seed() returned the previous value of .Random.seed (NULL if there was no previous value) things might be even easier. People should not have to know where .Random.seed is stored.
S+'s set.seed() accepts a value of .Random.seed but does not return the previous value. (If it is given an illegal value for .Random.seed it complains and sets it to a random value.) Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: rcpp-devel-boun...@lists.r-forge.r-project.org [mailto:rcpp-devel- > boun...@lists.r-forge.r-project.org] On Behalf Of Romain Francois > Sent: Friday, June 07, 2013 7:42 AM > To: Matteo Fasiolo > Cc: rcpp-de...@lists.r-forge.r-project.org > Subject: Re: [Rcpp-devel] Setting the R random seed from Rcpp > > > You can do something like this (i'm on my phone, so you might have to change > it): > > Environment g = Environment::global_env() ; > Environment::Binding RandomSeed = g[".Random.seed"] ; > > You get the current value of the binding like this: > > NumericVector someVariable = RandomSeed ; > > And then when you want to set the variable: you just do : > > RandomSeed = someVariable ; > > The Environment::Binding class acts a a proxy class. > > Romain > > > Le 7 juin 2013 à 16:22, Matteo Fasiolo <matteo.fasi...@gmail.com> a écrit : > > > Dear Rcpp experts, > > > > I would like to be able to store the R random seed from a Rcpp > > function and then reset it. In other words I would like to replicate > > the following code in Rcpp: > > > > savedSeed <- .Random.seed > > x <- Rfunction(parameters1); > > > > .Random.seed <- savedSeed > > x1 <- Rfunction(parameters2); > > > > where Rfunction simulates some random numbers and uses them > > but with different parameter values. > > Is it possible to do something similar in Rcpp? > > Probably using GetRNGstate() and PutRNGstate()? > > > > Thanks, > > > > Matteo > > _______________________________________________ > > Rcpp-devel mailing list > > rcpp-de...@lists.r-forge.r-project.org > > https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel > _______________________________________________ > Rcpp-devel mailing list > rcpp-de...@lists.r-forge.r-project.org > https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
