SLESSetDiagonalScale

 Tells SLES to diagonally scale the system before solving. This actually CHANGES the matrix (and right hand side).

Synopsis

#include "petscsles.h"    
int SLESSetDiagonalScale(SLES sles,PetscTruth scale)
Collective on SLES

Input Parameter

sles - the SLES context
scale - PETSC_TRUE or PETSC_FALSE

Notes

BE CAREFUL with this routine: it actually scales the matrix and right hand side that define the system. After the system is solved the matrix and right hand side remain scaled.

This routine is only used if the matrix and preconditioner matrix are the same thing.

If you use this with the PCType Eisenstat preconditioner than you can use the PCEisenstatNoDiagonalScaling() option, or -pc_eisenstat_no_diagonal_scaling to save some unneeded, redundant flops.

Keywords

SLES, set, options, prefix, database

See Also

SLESGetDiagonalScale(), SLESSetDiagonalScaleFix()

Level:intermediate
Location:src/sles/interface/sles.c
Index of all SLES routines
Table of Contents for all manual pages
Index of all manual pages