The extreme eigenvalues are the lowest and highest. A perfect preconditioner would give all eigenvalues = 1.0
Mark On Tue, Oct 4, 2022 at 1:03 PM feng wang <[email protected]> wrote: > Dear All, > > I am using the KSPComputeEigenvalues to understand the performance of my > preconditioner, and I am using the right-preconditioned GMRES with ASM. In > the user guide, it says this routine computes the extreme eigenvalues of > the preconditioned operator. If I understand it correctly, these > eigenvalues are the ones furthest away from (1,0)? If the preconditioning > is perfect, all the eigenvalues should be (1,0). > > Thanks, > Feng >
