Closed dpo closed 5 years ago
CP-Krylov solvers are formally equivalent to standard Krylov solvers with constraint preconditioners, provided that the starting guess satisfies exactly the second block of equations in the saddle-point system. According to this, I developed an implementation of standard CG-Lanczos for saddle-point systems (cpcglanczos_zero), where Bvk + Cqk is never computed because it is zero. This was done only for comparison purposes.
Ok. I propose that we remove this file from the repository or users may be confused. I can move it to a branch or remove it altogether. What do you prefer?
Please, move it to a branch.
See #6. The alternative-implementations
branch still contains cpcglanczos_zero.m
.
OK. Thanks.
cpcglanczos_zero
takesB
as input to computeu
. Does it have an advantage? No other method takesB
as input.