petsc-3.12.5 2020-03-29
PCEisenstatSetNoDiagonalScaling
Causes the Eisenstat preconditioner not to do additional diagonal preconditioning. For matrices with a constant along the diagonal, this may save a small amount of work.
Synopsis
#include "petscpc.h"
PetscErrorCode PCEisenstatSetNoDiagonalScaling(PC pc,PetscBool flg)
Logically Collective on PC
Input Parameters
| pc | - the preconditioner context
|
| flg | - PETSC_TRUE turns off diagonal scaling inside the algorithm
|
Options Database Key
-pc_eisenstat_no_diagonal_scaling -Activates PCEisenstatSetNoDiagonalScaling()
Note
If you use the KSPSetDiagonalScaling() or -ksp_diagonal_scale option then you will
likley want to use this routine since it will save you some unneeded flops.
See Also
PCEisenstatSetOmega()
Level
intermediate
Location
src/ksp/pc/impls/eisens/eisen.c
Implementations
PCEisenstatSetNoDiagonalScaling_Eisenstat in src/ksp/pc/impls/eisens/eisen.c
Index of all PC routines
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Index of all manual pages