petsc-3.6.2 2015-10-02
   
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 KPSSetDiagonalScaling() or -ksp_diagonal_scale option then you will
likley want to use this routine since it will save you some unneeded flops.
Keywords
 PC, Eisenstat, use, diagonal, scaling, SSOR
See Also
 PCEisenstatSetOmega()
Level:intermediate
Location:src/ksp/pc/impls/eisens/eisen.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages