Extending <i>R</i> with C++: A Brief Introduction to Rcpp

<p>R has always provided an application programming interface (API) for extensions. Based on the <i>C</i> language, it uses a number of macros and other low-level constructs to exchange data structures between the R process and any dynamically loaded component modules authors added to it. With the introduction of the <i>Rcpp</i> package, and its later refinements, this process has become considerably easier yet also more robust. By now, <i>Rcpp</i> has become the most popular extension mechanism for R. This article introduces <i>Rcpp</i>, and illustrates with several examples how the <i>Rcpp Attributes</i> mechanism in particular eases the transition of objects between R and C++ code. Supplementary materials for this article are available online.</p