| -ksp_chebyshev_eigenvalues <emin,emax> | - set approximations to the smallest and largest eigenvalues
of the preconditioned operator. If these are accurate you will get much faster convergence.
|
| -ksp_chebyshev_esteig <a,b,c,d> | - estimate eigenvalues using a Krylov method, then use this
transform for Chebyshev eigenvalue bounds (KSPChebyshevEstEigSet())
|
| -ksp_chebyshev_esteig_steps | - number of estimation steps
+ -ksp_chebyshev_esteig_random - use random right hand side for eigenvalue estimation (KSPChebyshevEstEigSetRandom())
|
Notes: The Chebyshev method requires both the matrix and preconditioner to
be symmetric positive (semi) definite.
Only support for left preconditioning.
Chebyshev is configured as a smoother by default, targetting the "upper" part of the spectrum.
The user should call KSPChebyshevSetEigenvalues() if they have eigenvalue estimates.
See Also
KSPCreate(), KSPSetType(), KSPType (for list of available types), KSP,
KSPChebyshevSetEigenvalues(), KSPChebyshevEstEigSet(), KSPChebyshevEstEigSetRandom(), KSPRICHARDSON, KSPCG, PCMG
Level:beginner
Location:src/ksp/ksp/impls/cheby/cheby.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages