'Ensmallen' is a templated C++ mathematical optimization library 
 (by the 'MLPACK' team) that provides a simple set of abstractions for writing an
 objective function to optimize. Provided within are various standard and
 cutting-edge optimizers that include full-batch gradient descent techniques, 
 small-batch techniques, gradient-free optimizers, and constrained optimization.
 The 'RcppEnsmallen' package includes the header files from the 'Ensmallen' library
 and pairs the appropriate header files from 'armadillo' through the 
 'RcppArmadillo' package. Therefore, users do not need to install 'Ensmallen' nor
 'Armadillo' to use 'RcppEnsmallen'. Note that 'Ensmallen' is licensed under 
 3-Clause BSD, 'Armadillo' starting from 7.800.0 is licensed under Apache License 2,
 'RcppArmadillo' (the 'Rcpp' bindings/bridge to 'Armadillo') is licensed under 
 the GNU GPL version 2 or later. Thus, 'RcppEnsmallen' is also licensed under
 similar terms. Note that 'Ensmallen' requires a compiler that supports 
 'C++11' and 'Armadillo' 9.800 or later.

Examples for Seamless R and C++ integration
 The 'Rcpp' package contains a C++ library that facilitates the integration of
 R and C++ in various ways. This package provides some usage examples.
 Note that the documentation in this package currently does not cover all the
 features in the package. The site <http://gallery.rcpp.org> regroups a large
 number of examples for 'Rcpp'.

The Google 'FarmHash' family of hash functions is used by
 the Google 'BigQuery' data warehouse via the 'FARM_FINGERPRINT'
 function. This package permits to calculate these hash digest
 fingerprints directly from R, and uses the included 'FarmHash'
 files written by G. Pike and copyrighted by Google, Inc.

The header-only 'C++' template library 'FastAD' for automatic
 differentiation <https://github.com/JamesYang007/FastAD> is provided by
 this package, along with a few illustrative examples that can all be called
 from R.

Converting ascii text into (floating-point) numeric values is a
 very common problem. The 'fast_float' header-only C++ library by Daniel Lemire
 does it very well and very fast at up to or over to 1 gigabyte per second as
 described in more detail in <arXiv:2101.11408>. 'fast_float' is licensed under
 the Apache 2.0 license and provided here for use by other R packages via a simple
 'LinkingTo:' statement.