User-difined PC

[Lisandro Dalcin]

BTW, I'm pretty sure that long, long time ago I asked for this, and
some of you rejected the idea, but I cannot remember the rationale
right now.  The current state of PCShell somewhat complicates the
access to internal PC stuff (eg. linear operators).


On Mon, Sep 22, 2008 at 1:08 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
> On Sep 22, 2008, at 7:59 AM, Dave May wrote:
>
>>
>>
>> Why is the first pointer in PCSHELL operations the user context
>> whereas in MATSHELL the first pointer is of type Mat ?? Seems slightly
>> inconsistent.
>>
>   Good question, these were done at different times and only later
> did we realize the inconsistency. This is something that should be fixed in
> petsc-dev.
>
>   Barry
>
> I guess the first argument for the PCSHELL should become the pc.
>
>>
>>
>> On Mon, Sep 22, 2008 at 8:31 PM, Michel Cancelliere
>> <fernandez858 at gmail.com> wrote:
>>>
>>> Hello,
>>>
>>> I have problems with the implementation of a user-defined pc, basically
>>> my
>>> program is in a cycle, for with which he is called by matlab each time it
>>> seeks to solve a linear system, the problem is that in the first
>>> iteration
>>> of the for-cycle  the preconditioner works very well, then fails to
>>> convergence. It may be some parameters that I setting wrong?
>>> I'am attaching my program code.
>>>
>>> Thank you,
>>>
>>> Michel
>>>
>>
>
>



-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
PTLC - Güemes 3450, (3000) Santa Fe, Argentina
Tel/Fax: +54-(0)342-451.1594