[petsc-users] Pre-conditioner for parallel CFD simulation

[Thomas Witkowski]

Jed Brown wrote:
> On Fri, Apr 15, 2011 at 12:06, Thomas Witkowski 
> <thomas.witkowski at tu-dresden.de 
> <mailto:thomas.witkowski at tu-dresden.de>> wrote:
>
>     Which package must be installed to make use of "ml" (algebraic
>     multigrid?) as a preconditioner?
>
>
> ML, --download-ml
> also -pc_type hypre (BoomerAMG is default) from, you guessed it, 
> Hypre, --download-hypre
But it works with MatAIJ with MatSetBlockSize(x). What is the difference 
between using MatBAIJ and MatAIJ with setting the block size directly?