r-cran-numderiv - 2016.8-1.1-3 main

This package provide methods for calculating (usually) accurate
numerical first and second order derivatives. Accurate calculations
are done using Richardson's extrapolation or, when applicable, a
complex step derivative is available. A simple difference method is
also provided. Simple difference is (usually) less accurate but is
much quicker than Richardson's extrapolation and provides a useful
cross-check. Methods are provided for real scalar and vector valued
functions.