Preconditioner interface
Currently, the preconditioner interface is very similar to the Solver interface. However, when calling solve(A, x, b)
in a preconditioner, the b
variable gets changed instead of the x
variable. This makes it impossible to use a general solver as a preconditioner. For instance, multgrid within a PCG solver.
My proposal: Swap the meaning of x
and b
in all preconditioners located in solvers/preconditioners
. Make this swap consistent in solvers where preconditioners are currently supported, e.g., CGSolver
, MinResSolver
, and maybe others?