Algorithmic roadmap

[haampie]

Open issues:

• Deflation
  • Early locking (Improved & early locking of converged Ritz vectors #71) --- implemented via Krylov-Schur
  • Purging / removing eigenvalues that are unwanted (http://www.netlib.org/utk/people/JackDongarra/etemplates/node232.html). Plus: determining if an eigenvalue is unwanted (Steer convergence #80) --- implemented via Krylov-Schur
• Reordering of the Schur form such that eigenvalues closest to the specified target appear first (more or less covered by Improved & early locking of converged Ritz vectors #71)
• B-inner product for generalized problems (Matrix-induced (semi-)inner product when B ≥ 0. #50)
• Tricks: improve eigenvector approximation in certain spectral transformations (http://www.netlib.org/utk/people/JackDongarra/etemplates/node233.html)

Finished:

• Handle close-to-0 eigenvalue better; stopping criterion is probably to strict for them now. (Make sure the convergence criterion for 0 eigenvalues is attainable #72)