PCEisenstatGetNoDiagonalScaling#
Tells if 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 PCEisenstatGetNoDiagonalScaling(PC pc, PetscBool *flg)
Logically Collective
Input Parameter#
- pc - the preconditioner context 
Output Parameter#
- flg - - PETSC_TRUEmeans there is no diagonal scaling applied
Options Database Key#
- -pc_eisenstat_no_diagonal_scaling - Activates - PCEisenstatSetNoDiagonalScaling()
Note#
If you use the KSPSetDiagonalScaling() or -ksp_diagonal_scale option then you will likely want to use this routine since it will save you some unneeded flops.
See Also#
Level#
intermediate
Location#
Implementations#
PCEisenstatGetNoDiagonalScaling_Eisenstat() in src/ksp/pc/impls/eisens/eisen.c
Index of all PC routines
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Index of all manual pages