Rcpp Module example

rcpp.modules.r

# Borrowed from http://dirk.eddelbuettel.com/papers/rcpp_workshop_part_3_advanced.pdf

require(Rcpp)
require(inline)
require(testthat)

fx <- cxxfunction(,"",includes=
'
double norm( double x, double y ){
  return sqrt( x*x + y*y) ;
}
RCPP_MODULE(foo){
  function( "norm", &norm ) ;
}
', plugin="Rcpp")

foo <- Module("foo",getDynLib(fx))
norm <- function(x,y) sqrt(x*x + y*y)

test_that("Rcpp module agrees with R version",{
  expect_that(foo$norm(3,5),equals(norm(3,5)))
})