## ----c_sum--------------------------------------------------------------- c_sum <- function(x) .C("c_sum", as.numeric(x), length(x), answer=numeric(1))$answer ## ----c_sum-invoke, eval=FALSE-------------------------------------------- ## dyn.load("~/c_sum.so") ## c_sum(1:100) ## ----c-headers----------------------------------------------------------- R.home("include") ## ----call_sum------------------------------------------------------------ call_sum <- function(x) .Call("call_sum", as.numeric(x)) ## ----rccp-compile, eval=FALSE-------------------------------------------- ## library(Rcpp) ## sourceCpp("~/rcpp_sum.cpp") ## ----eval=FALSE---------------------------------------------------------- ## rcpp_sum(1:10)