High level functions for doing parallel programming with Rcpp.
For example, the parallelFor function can be used to convert the work of
a standard serial "for" loop into a parallel one and the parallelReduce
function can be used for accumulating aggregate or other values.
The high level interface enables safe and robust parallel programming without
direct manipulation of operating system threads. On Windows, OS X, and Linux
systems the underlying implementation is based on Intel TBB (Threading Building
Blocks). On other platforms a less-performant fallback implementation based on the
TinyThread library is used.