search for: matrixxd

...he actual parallel code portions in all examples -- types RVector and RMatrix do NOT connect back to R. There are several working examples. That is also what the OpenMP examples at the Rcpp Gallery do. Charles seems to be replying 'but I use XPtr' or 'I use XPtr on arma::mat or Eigen::Matrixxd' and seems to forget that these are proxy objects to SEXPs. XPtr just wrap the SEXP for external pointers; Arma's and Eigen's matrices are performant via RcppArmadillo and RcppEigen because we use R memory via proxies. All of that is 'too close to R' for comfort. So the short...

...n all examples -- > types RVector and RMatrix do NOT connect back to R. There are several > working > examples. That is also what the OpenMP examples at the Rcpp Gallery do. > > Charles seems to be replying 'but I use XPtr' or 'I use XPtr on arma::mat > or > Eigen::Matrixxd' and seems to forget that these are proxy objects to SEXPs. > XPtr just wrap the SEXP for external pointers; Arma's and Eigen's matrices > are performant via RcppArmadillo and RcppEigen because we use R memory via > proxies. All of that is 'too close to R' for comfort....

R Developers, Could someone help explain what it means that R is single threaded? I am trying to understand what is actually going on inside R when users want to parallelize code. For example, using mclapply or foreach (with some backend) somehow allows users to benefit from multiple CPUs. Similarly there is the RcppParallel package for RMatrix/RVector objects. But none of these address the