This might be a bit off-topic... I have C++ code that uses Eigen dynamic matrices. Would someone have a small and simple example of using R functions on MatrixXd data? I found Rinside package (http://dirk.eddelbuettel.com/code/rinside.html), but it would be great to be able to use it without having to make a copy of Eigen matrices into NumericMatrix in R.

Thanks.

You can use .data() to get a pointer to the first element of the matrix, and .outerStride() to get the leading dimension. Then how to make use of them with R is out of my knowledge. You should ask on a R forum.

have you looked at the sources of the Rclusterpp package? I'm not sure but it seems to me it is calling some R functions
http://cran.r-project.org/web/packages/ ... index.html

For the moment, there are only two R packages using eigen
(the other one is sparseLTSEigen).

Thanks.

I was also pointed to RcppEigen package on the Rcpp mailing list.