[Trilinos-Users] Aztec, DD-prec and reuse

[Simone Deparis]

Mike,

I am migrating to ifpack, it is defently what I need at the end.
Thank you very much
Simone

Simone Deparis wrote:
> Mike,
> 
> Mike Heroux wrote:
> 
>>Simone,
>>
>>One general comment:  
>>
>>You might consider using Ifpack for preconditioners for AztecOO.  Ifpack has
>>a much cleaner design and provides far more preconditioning capabilities.
>>In contrast, the interface to AztecOO's native preconditioners is and will
>>always be clumsy for advanced use cases.  This is because we have to live
>>within the constraints of the underlying Aztec capabilities which are not
>>object-oriented and quite fragile under changes.
> 
> 
> I understand. If I can not solve this issue, I'll migrate to ifpack
> 
> 
>>Regarding AZ_reuse:  
>>
>>Sorry to mislead you.  You should set options[AZ_pre_calc] = AZ_reuse
>>*after* the first call to Iterate, but before the second.  You should not
>>set options[AZ_pre_calc] = AZ_reuse *at all* if using the
>>Construct/DestroyPreconditioner() methods, since this setting is handled for
>>you.
> 
> 
> Ok. But I get the error also when using
> Construct/DestroyPreconditioner() and *not* set  options[AZ_pre_calc]
> (which as yuo say is handeld by ConstrucPreconditioner()
> 
> Is it possible that the preconditioner is destroyed anyway?:
> in fact Iterate() calls AZ_solve which at the end calls
> AZ_precond_destroy. So I understand that the preconditioner is destroyed.
> In iterate:
> 
>   if (prec_allocated == 1) {
>     AZ_precond_destroy(&Prec_);
>     Prec_ = 0;
>     prec_allocated = 0;
>   }
> 
> where:
> 
> void AZ_precond_destroy(AZ_PRECOND **precond)
> {
>   if ( (*precond) == NULL) return;
>    if ( (*precond)->print_string != NULL) AZ_free(
> (*precond)->print_string);
>    AZ_free(*precond);
>    *precond = NULL;
> }
> 
> 
> Am I wrong?
> 
> Simone
> 
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> 

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                                    Simone Deparis
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