C++ classes to embed R in C++ (and C) applications A C++ class providing the R interpreter is offered by this package making it easier to have "R inside" your C++ application. As R itself is embedded into your application, a shared library build of R is required. This works on Linux, OS X and even on Windows provided you use the same tools used to build R itself. Numerous examples are provided in the nine subdirectories of the examples/ directory of the installed package: standard, 'mpi' (for parallel computing), 'qt' (showing how to embed 'RInside' inside a Qt GUI application), 'wt' (showing how to build a "web-application" using the Wt toolkit), 'armadillo' (for 'RInside' use with 'RcppArmadillo'), 'eigen' (for 'RInside' use with 'RcppEigen'), and 'c_interface' for a basic C interface and 'Ruby' illustration. The examples use 'GNUmakefile(s)' with GNU extensions, so a GNU make is required (and will use the 'GNUmakefile' automatically). 'Doxygen'-generated documentation of the C++ classes is available at the 'RInside' website as well.
The RInside package provides a few classes for seamless embedding of R inside of C++ applications by relying on Rcpp.
Provided with the package itself are nine subdirectories with examples: from more than a dozen basic command-line examples (in directory
standard) to graphical user-interfaces (using both Qt and Wt), linear algebra with
Armadillo and Eigen, parallel computing with MPI to a
sandboxed server, and (since release 0.2.16) a simple (and more limited) interface for embedding insice C applications.
The simplest example (modulo its header) is examples/standard/rinside_sample0.cpp
#include <RInside.h> // for the embedded R via RInside
int main(int argc, char *argv[]) {
RInside R(argc, argv); // create an embedded R instance
R["txt"] = "Hello, world!\n"; // assign a char* (string) to 'txt'
R.parseEvalQ("cat(txt)"); // eval the init string, ignoring any returns
exit(0);
}
The Qt example directory produces this application for showing how to use R (to estimate densities) inside a C++ executable (providing the GUI):

The code is portable across operating systems. Similar, the Wt example directory contains this C++-based web application doing the same:

The RInside web page has some more details.
Dirk Eddelbuettel, Romain Francois, and Lance Bachmeier
GPL (>= 2)