An even more major rewrite of the package. All ACM code was removed, and replaced with original R/C++ implementations.

The sparseHessianFD class is now implemented as an R reference class, and not as an Rcpp module. The sparseHessianFD.new function is deprecated. Instead, use sparseHessianFD to initialize an object. Initialization once again takes place in a single step.

The ‘direct’ computation method has been removed. All computation uses the ‘indirect’ triangular substitution method. The ‘direct’ argument in the initializer for the sparseHessianFD class is now deprecated, and remains solely for compatibility with older versions of the package.

There is a new vignette with a lot more detail about what the package does and how it works.

New matrix helper functions Matrix.to.Pointers and Coord.to.Pointers. The Coord.to.Pattern.Matrix function is deprecated. Use the spMatrix or sparseMatrix functions in the Matrix package instead.

With the removal of ACM-copyrighted code, this package is now licensed under the MPL 2.0.