> On 19 Dec 2018, at 9:46 AM, Stefano Zampini wrote:
>
> Pierre,
>
> The details of the inner solvers for PCFIELDSPLIT are not known if you don’t
> call PCSetUp, so the cascade approach should be preferred.
OK, great! It was actually not that big of a deal to implement.
Thanks,
Pierre
> After PCSetUp, you can access the inner solves, see e.g.
> https://bitbucket.org/petsc/petsc/src/4ddd364d454d7bce974e92e0b5bd4f4516dbff02/src/ksp/pc/impls/bddc/bddc.c#lines-2715
>> On Dec 19, 2018, at 9:01 AM, Pierre Jolivet via petsc-dev
>> wrote:
>>
>> Hello,
>> I have a PCFIELDSPLIT where the fields are defined by a MATNEST
>> “decomposition”.
>> Right now, I am first defining the KSP of the diagonal blocks of the
>> MATNEST, which are themselves PCFIELDSPLIT, then creating the Mat itself,
>> and eventually I’d like to solve systems with the complete MATNEST.
>> However, the KSP and PC options of the “first level" inner solvers are not
>> propagated to the global outer solver.
>> Can this be achieved somehow, or do I always need to set the options in the
>> opposite direction (first outer solver, then inner solvers, e.g., through a
>> cascade of PCFieldSplitGetSubKSP)?
>>
>> Thanks in advance,
>> Pierre
>
