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added 'pi by Simulation' example
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‎ChangeLog‎

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2012-11-21 Dirk Eddelbuettel <edd@debian.org>
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* inst/examples/Misc/piBySimulation.r: New simple example using Rcpp
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attributes in a 'compute pi by simulation in R and C++' exercise
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* inst/examples/Misc/piSugar.cpp: Corresponding C++ variant
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2012-11-21 Romain Francois <romain@r-enthusiasts.com>
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* include/Rcpp/iostream/Rostream.h: Fix warning given by -Wreorder
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2012-11-20 Romain Francois <romain@r-enthusiasts.com>
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* include/Rcpp/iostream/Rostream.h: change order of initiaization in
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ctor. was making solaris compiler unhappy
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* include/Rcpp/iostream/Rostream.h: change order of initiaization in
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ctor. was making solaris compiler unhappy
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* include/Rcpp/stats/random/rnorm.h: not using function pointer
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generators, as this generates (anachronisms) warning on solaris. Also,
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this version is more efficient since there is no need to dereference
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the function pointer
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generators, as this generates (anachronisms) warning on
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solaris. Also, this version is more efficient since there is no need
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to dereference the function pointer
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2012-11-19 JJ Allaire <jj@rstudio.org>
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2012-11-18 JJ Allaire <jj@rstudio.org>
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* R/Attributes.R: sourceCpp embedded R code; print warning if
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no export attributes are found in source file
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* R/Attributes.R: sourceCpp embedded R code; print warning if no
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export attributes are found in source file
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* src/AttributesParser.h: sourceCpp embedded R code
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* src/AttributesParser.cpp: sourceCpp embedded R code; new scheme
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for mixing user and generated C++ headers

‎inst/NEWS.Rd‎

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\itemize{
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\item Changes in Rcpp sugar:
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\itemize{
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\item New functions: \code{setdiff}, \code{union_}, \code{intersect}
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\item New functions: \code{setdiff}, \code{union_}, \code{intersect}
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\code{setequal}, \code{in}, \code{min}, \code{max}, \code{range},
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\code{match}
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}
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\itemize{
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\item New function \code{areMacrosDefined}
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}
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\item Miscellaneous changes:
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\itemize{
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\item New example 'pi simulation' using R and C++ via Rcpp attributes
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}
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}
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}
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\section{Changes in Rcpp version 0.10.0 (2012-11-13)}{

‎inst/examples/Misc/piBySimulation.r‎

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#!/usr/bin/r
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library(Rcpp)
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library(rbenchmark)
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piR <- function(N) {
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x <- runif(N)
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y <- runif(N)
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d <- sqrt(x^2 + y^2)
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return(4 * sum(d < 1.0) / N)
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}
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sourceCpp("piSugar.cpp")
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N <- 1e6
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set.seed(42)
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resR <- piR(N)
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set.seed(42)
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resCpp <- piSugar(N)
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## important: check results are identical with RNG seeded
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stopifnot(identical(resR, resCpp))
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res <- benchmark(piR(N), piSugar(N), order="relative")
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print(res[,1:4])

‎inst/examples/Misc/piSugar.cpp‎

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#include <Rcpp.h>
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using namespace Rcpp;
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// [[Rcpp::export]]
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double piSugar(const int N) {
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RNGScope scope; // ensure RNG gets set/reset
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NumericVector x = runif(N);
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NumericVector y = runif(N);
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NumericVector d = sqrt(x*x + y*y);
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return 4.0 * sum(d < 1.0) / N;
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}

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