Interoperability between 'Rcpp' and the 'C++11' array and tuple
    types. Linking to this package allows fixed-length 'std::array' objects to
    be converted to and from equivalent R vectors, and 'std::tuple' objects
    converted to lists, via the as() and wrap() functions. There is also
    experimental support for 'std::span' from 'C++20'.

Provides an interface from R to the 'autodiff' library
    <https://autodiff.github.io/>, a modern header-only
    C++ library for automatic differentiation. Unlike numerical
    differentiation, automatic differentiation computes derivatives of
    functions to machine precision without truncation error, using either
    forward or reverse mode. The 'autodiff' header files are shipped with
    this package so that other R packages can use them by including
    'Rcppautodiff' in the 'LinkingTo' field of their 'DESCRIPTION' file.
    Example programs demonstrate computing derivatives of single-variable
    and multi-variable functions, gradient vectors, Jacobian matrices and
    derivatives with respect to parameters, using 'Rcpp' and 'RcppEigen'.

Access to Boost Date_Time functionality for dates,
 durations (both for days and date time objects), time zones, and 
 posix time ('ptime') is provided by using 'Rcpp modules'. The 
 posix time implementation can support high-resolution of up to 
 nano-second  precision by using 96 bits (instead of 64 with R)
 to present a 'ptime' object (but this needs recompilation with
 a #define set).

Exports an 'Rcpp' interface for the Bessel functions in the 'Bessel' package, which can then be called from the 'C++' code of other packages. For the original 'Fortran' implementation of these functions see Amos (1995) <doi:10.1145/212066.212078>.

Features the multiple polynomial quadratic sieve (MPQS) algorithm
    for factoring large integers and a vectorized factoring function that
    returns the complete factorization of an integer. The MPQS is based off of
    the seminal work of Carl Pomerance (1984) <doi:10.1007/3-540-39757-4_17>
    along with the modification of multiple polynomials introduced by Peter
    Montgomery and J. Davis as outlined by Robert D. Silverman (1987)
    <doi:10.1090/S0025-5718-1987-0866119-8>. Utilizes the C library
    GMP (GNU Multiple Precision Arithmetic). For smaller integers, a simple
    Elliptic Curve algorithm is attempted followed by a constrained version of 
    Pollard's rho algorithm. The Pollard's rho algorithm is the same algorithm
    used by the factorize function in the 'gmp' package.