Rewrote most of the code for the HypIgu package with the goal of simplifying, repairing, and enhancing the code.
Some of the changes include:
- Changed the LatticeOfFlats data structure to GradedPoset as a unifying class for the main objects of study:
- intersection posets of hyperplane arrangements
- lattices of flats of matroids
- graded $R$-labeled posets
- GradedPoset has far fewer methods, and relies on other algorithms for most of what it does (notably computing lattice of flats and intersection posets quickly).
- Removed a few rational functions: analytic and atom zeta functions. At least for now...
- Simplified the input data for the other rational functions.
- Fixed a bug with the `BraidArrangementIgusa`.
- Removed the parallel code and the internal database. This will be brought back in better form later.