**petsc-3.15.0 2021-04-05**

# KSPSetDiagonalScaleFix

Tells KSP to diagonally scale the system back after solving.
### Synopsis

#include "petscksp.h"
#include "petscmat.h"
PetscErrorCode KSPSetDiagonalScaleFix(KSP ksp,PetscBool fix)

Logically Collective on ksp

### Input Parameter

### Notes

Must be called after KSPSetDiagonalScale()
Using this will slow things down, because it rescales the matrix before and
after each linear solve. This is intended mainly for testing to allow one
to easily get back the original system to make sure the solution computed is
accurate enough.

### See Also

KSPGetDiagonalScale(), KSPSetDiagonalScale(), KSPGetDiagonalScaleFix(), KSP

### Level

intermediate

### Location

src/ksp/ksp/interface/itfunc.c

Index of all KSP routines

Table of Contents for all manual pages

Index of all manual pages