How about using a fixed number of Richardson iterations as a Krylov preconditioner to a GMRES solver? Would that lead to a linear operation?
On Sat, Apr 30, 2022 at 8:21 PM Jed Brown <[email protected]> wrote: > In general, no. A fixed number of Krylov iterations (CG, GMRES, etc.) is a > nonlinear operation. > > A fixed number of iterations of a method with a fixed polynomial, such as > Chebyshev, is a linear operation so you don't need a flexible outer method. > > Ramakrishnan Thirumalaisamy <[email protected]> writes: > > > Hi, > > > > I have a Krylov solver with a preconditioner that is also a Krylov > solver. > > I know I can use "fgmres" for the outer solver but can I use gmres for > the > > outer solver with a fixed number of iterations in the Krylov > > preconditioners? > > > > > > Thanks, > > Rama > -- --Amneet
