[petsc-users] How to change KSP tolerance during SNES steps

[Barry Smith]

On Apr 26, 2012, at 10:31 AM, behzad baghapour wrote:

> Thanks. It did work!
> 
> Then how I should do for changing the tolerance of ksp? (changing from inexact into exact Newton phase)
> 
> Thanks a lot,
> 


  Hong already answered that


behzad :

I set SNES with -snes_ksp_ew to solve the system with inexact method. I want to reset the SNES into exact Newton with changing the KSP rtol at final iterations (in full Newton phase). How can I reset the KSP tolerance after specific iterations of SNES?
You can use SNESMonitorSet() and write your own monitor function to do this:
http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/SNES/SNESMonitorSet.html 

Hong