- Ensure specification of bd,eps,mxiter parameters match across all calls to the Newton Raphson algorithms.
- Add tests for
`interp_gen_D1`

at 0. - Added package documentation.

- The package now has a C++ backend, by converting the four Newton-Raphson algorithms and their dependencies from R to C++.

Smaller changes:

- Renamed
`tau`

argument to`p`

in IG and IGL quantile functions. - Removed
`igl_gen_DD`

and`igamma()`

internal functions, which were not used for copula quantities.

- Added a
`NEWS.md`

file to track changes to the package. - Completed the collection of distributional quantities to match that of the CopulaModel package.
- Computations of quantile functions are now more robust.
- Changed the parameterization of the copula families to make them more numerically stable.
- Small values of the parameter
`alpha`

(previously =`k - 1`

) are now reliable.

- Small values of the parameter
- Placed the theta and alpha parameters of the IG copula as their own arguments.

- Computational tools for IG and IGL copulas are now available, using the original parameterization of these copulas as defined in Coia (2017) thesis.