[petsc-users] Hypre through Petsc: BoomerAMG options

[Barry Smith]

On Aug 29, 2012, at 9:59 AM, Arun Kamath <arun.kamath.m at gmail.com> wrote:

> Hei!
> I was going through the Petsc user archives when I came across a
> discussion with Barry Smith regarding use of BoomerAMG through Petsc
> (http://lists.mcs.anl.gov/pipermail/petsc-users/2006-October/000692.html).
> 
> What I did understand from that is some of the Hypre options cannot
> be accessed through Petsc. But options like Pilut are available as preconditioners or solvers depnding on ksptype.
> I am trying to use ILU smoothening to BoomerAMG (Hypre's manual lists the smoothers available and the function calls). The questions that remain after going through that discussion are:
> 
> 1.  Can a smoothening option in hypre's boomerAMG could be chosen at all using Petsc?

     Currently all the BoomerAMG options that we DIRECTLY support can be found in the routine PCSetFromOptions_HYPRE_BoomerAMG() in the file src/ksp/pc/impls/hypre

     This was done a few years ago so may not include newer options added to BoomerAMG.  If there are new options for BoomerAMG you would like added let us know and we can easily add them.  But note that hypre is not composible in the same way as PETSc; you cannot mix parts of PILUT with BoomerAMG etc.


> 2.  Could the function calls phrases used in Hypre itself be somehow employed in the Petsc code?

    I have added PCHYPREGetSolver(PC pc,HYPRE_Solver *hsolver) to petsc-dev giving you access to the hypre solver so you can make function calls on it.  Call this after you have called KSPSetFromOptions() (or SNESFromOptions() if you are using the nonlinear solvers).

    
> 
> Would be really grateful for any advice. Since I am using an IDE to build the code, non-command line option tricks would also be of great help.

   This is a good place for a configuration file; the filename is passed to PetscInitialize()   (or the default filename is petscrc). Here list the PETSc options one per line, you can add comments with #     Thus even if you have many options it is easy to switch them around without recompiling the code.

   Barry


> 
> Arun Kamath
> NTNU Trondheim