Network Analysis and Visualization (igraph)
Routines for simple graphs and network analysis. It can handle large graphs very well and provides functions for generating random and regular graphs, graph visualization, centrality methods and much more.

Seamless R and C++ Integration (Rcpp)
The ‘Rcpp’ package provides R functions as well as C++ classes which offer a seamless integration of R and C++. Many R data types and objects can be mapped back and forth to C++ equivalents which facilitates both writing of new code as well as easier integration of third-party libraries. Documentation about ‘Rcpp’ is provided by several vignettes included in this package, via the ‘Rcpp Gallery’ site at <>, the paper by Eddelbuettel and Francois (2011, JSS), and the book by Eddelbuettel (2013, Springer); see ‘citation(‘Rcpp’)’ for details on these last two.

Convert ‘RUnit’ Test Functions into ‘testthat’ Tests (runittotestthat)
Automatically convert a file or package worth of ‘RUnit’ test functions into ‘testthat’ tests.