Hello,
First of all I'm new to PETSc so please be pacient with me.
I'm trying to solve 2 linear systems with the same A matrix using
superlu_dist, and so i'm using the same ksp context for both systems.
The matrix is a square matrix of 84719 with 351289 nonzero elements.
The time for the
> You need to run for much more iterations to get any kind of reliable
>singular values. Use something like at least -ksp_gmres_restart 100
>-ksp_max_it 100 and see what happens to the singular values.
>
>Barry
Barry, Jed,
I followed your advice, this is what happens to the singular values
(
On Oct 26, 2011, at 10:34 AM, Bogdan Dita wrote:
>
> Hello,
>
> First of all I'm new to PETSc so please be pacient with me.
> I'm trying to solve 2 linear systems with the same A matrix using
> superlu_dist, and so i'm using the same ksp context for both systems.
> The matrix is a square
What happens at restart to the residual norm? That is does the residual norm
change dramatically on the first iteration after the restart? This is an
indication of loss of orthogonality.
You can put in a restart of 1000 and run for 1000 iterations. What happens
then?
Barry
On Oct 26
s.anl.gov/pipermail/petsc-users/attachments/20111026/b7655150/attachment.htm>
If you call KSPSetUp() directly it calls PCSetUp(). If you do not call
KSPSetUp() directly it is called at the beginning of KSPSolve() the FIRST time
KSPSolve() is called after a KSPSetOperators(). If KSPSolve() is called
repeatedly without calling KSPSetFromOperators() again (meaning changi
When will "PCSetUp" set up new PC?
1), PCSetUp(): Setting up PC with same nonzero pattern
2), [0] PCSetUp(): Setting up new PC
Thanks,
Debao
-Original Message-
From: petsc-users-bounces at mcs.anl.gov
[mailto:petsc-users-boun...@mcs.anl.gov] On Behalf Of Barry Smith
Sent: Tuesday, October
