Well I don't bother to much about which PC is use. I just wanted to look
what's possible. One can of course come up with some kind of augmented
Lagrange formulation, but then you end up with a saddle point problem.
On 19.05.2016 14:41, Matthew Knepley wrote:
On Thu, May 19, 2016 at 7:39 AM, Elias Karabelas
<[email protected] <mailto:[email protected]>>
wrote:
Ok maybe I should go a little bit more into detail. I have some
stokes problem in a bifurcating Y-tube. Now I would like to
enforce some prescribed flux splits at the outlets. After some
literature research i found a Nitsche method to do that. And if
you consider the additional billinear forms you end up with some
nonlocal coupling terms at the outlets (which are those vectors I
talked earlier)
Keep the Cc.
I can see that you might have that formulation, but how you would
incorporate that into AMG, I have no idea.
Matt
On 19.05.2016 14:31, Matthew Knepley wrote:
On Thu, May 19, 2016 at 7:29 AM, Elias Karabelas
<[email protected]
<mailto:[email protected]>> wrote:
maybe something with PCSHELL?
No, I mean that I do not understand what algorithm you might use
(apart from the implementation).
Matt
On 19.05.2016 14:28, Matthew Knepley wrote:
On Thu, May 19, 2016 at 2:48 AM, Elias Karabelas
<[email protected]
<mailto:[email protected]>> wrote:
Dear all,
I have a question about preconditioned solvers. So, I
have a Sparsematrix, say A, and now for some reason I
would like to add some rank-one term u v^T to that matrix.
As far as I know about Petsc, I can define the action of
this matrix with MatShell. But is it possible to adapt
the preconditioner (like a AMG) of my KSP to handle that
kind of MatShell?
I do not know how you would do that. Its possible other
people have ideas.
Thanks,
Matt
Kind Regards
Elias
--
Dr Elias Karabelas
Medical University of Graz
Institute of Biophysics
Harrachgasse 21/IV
8010 Graz, Austria
Phone: +43 316 380 7759 <tel:%2B43%20316%20380%207759>
Email: [email protected]
<mailto:[email protected]>
Web :
http://forschung.medunigraz.at/fodok/staff?name=EliasKarabelas
--
What most experimenters take for granted before they begin
their experiments is infinitely more interesting than any
results to which their experiments lead.
-- Norbert Wiener
--
Dr Elias Karabelas
Medical University of Graz
Institute of Biophysics
Harrachgasse 21/IV
8010 Graz, Austria
Phone:+43 316 380 7759 <tel:%2B43%20316%20380%207759>
Email:[email protected]
<mailto:[email protected]>
Web :http://forschung.medunigraz.at/fodok/staff?name=EliasKarabelas
--
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to
which their experiments lead.
-- Norbert Wiener
--
Dr Elias Karabelas
Medical University of Graz
Institute of Biophysics
Harrachgasse 21/IV
8010 Graz, Austria
Phone:+43 316 380 7759 <tel:%2B43%20316%20380%207759>
Email:[email protected] <mailto:[email protected]>
Web :http://forschung.medunigraz.at/fodok/staff?name=EliasKarabelas
--
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which
their experiments lead.
-- Norbert Wiener
--
Dr Elias Karabelas
Medical University of Graz
Institute of Biophysics
Harrachgasse 21/IV
8010 Graz, Austria
Phone: +43 316 380 7759
Email: [email protected]
Web : http://forschung.medunigraz.at/fodok/staff?name=EliasKarabelas
