> On 20 Apr 2023, at 10:28 PM, Zhang, Hong wrote:
>
> Pierre,
> 1) Is there any hope to get PDIPDM to use a MatNest?
>
> KKT matrix is indefinite and ill-conditioned, which must be solved using a
> direct matrix factorization method.
But you are using PCBJACOBI in the paper you attached?
In
Pierre,
1) Is there any hope to get PDIPDM to use a MatNest?
KKT matrix is indefinite and ill-conditioned, which must be solved using a
direct matrix factorization method. For the current implementation, we use
MUMPS Cholesky as default. To use MatNest, what direct solver to use,
SCHUR_FACTOR?
Hong,
1) Is there any hope to get PDIPDM to use a MatNest?
2) Is this fixed
https://lists.mcs.anl.gov/pipermail/petsc-dev/2020-September/026398.html ?
I cannot get users to transition away from Ipopt because of these two missing
features.
Thanks,
Pierre
> On 20 Apr 2023, at 5:47 PM, Zhang,
Hi Matt,
thanks for sharing the literature.
Would you suggest any monolitic approach for the mpiaij/mpibaij matrix
instead of fieldsplit?
I did some blind search using gamg/hypre and they look terribile. I guess i
am missing a trick, probaly they are not the way to go?
Thanks!
Il Lun 17 Apr
On Thu, Apr 20, 2023 at 6:13 AM Karthikeyan Chockalingam - STFC UKRI via
petsc-users wrote:
> Hello,
>
>
>
> I created a new thread, thought would it be more appropriate (and is a
> continuation of my previous post). I want to construct the below K matrix
> (which is composed of submatrices)
>
>
Hello,
I created a new thread, thought would it be more appropriate (and is a
continuation of my previous post). I want to construct the below K matrix
(which is composed of submatrices)
K = [A P^T
P 0]
Where K is of type MatMPIAIJ. I first constructed the top left [A] using
Thanks a lot Pierre, I use PCGAMG as I type this answer. Not only that it
works, but converges much faster than PCASM :-)
Have a great day,
Bojan
On Thu, Apr 20, 2023 at 8:07 AM Pierre Jolivet
wrote:
>
> > On 20 Apr 2023, at 7:53 AM, Bojan Niceno <
> bojan.niceno.scient...@gmail.com>
> On 20 Apr 2023, at 7:53 AM, Bojan Niceno
> wrote:
>
> Dear all,
>
>
> I am solving a Laplace equation with finite volume method on an unstructured
> grid with a Fortran code I have developed, and PETSc 3.19 library.
>
> I first used cg solver with asm preconditioner, which converges
