Actually I don't. Sorry, I'm fairly new to using SLEPc. That would
explain why when I use krylov methods convergence is extremely slow
(~15,000 iterations for the first eigenpair), but when I use other
methods such as lobpcg and rqcg, which I've heard use preconditioners
automatically, convergenc
Do you precondition your eigenvalue problem? If not, you should. Let
us know what structure your matrix has and which blocks (if there are
any) include which physics.
Regards
Julian
On Mon, Oct 17, 2016 at 5:30 PM, Christopher Pierce wrote:
> I've implemented my application using MatGetSubMatrix
I've implemented my application using MatGetSubMatrix and the solvers
appear to be converging correctly now, just slowly. I assume that this
is due to the clustering of eigenvalues inherent to the problem that I'm
using, however. I think that this should be enough to get me on track
to solving pr
Thank You,
That looks like what I need to do if the highly degenerate eigenpairs
are my problem. I'll try that out this week and see if that helps.
Chris
On 10/13/16 20:01, Barry Smith wrote:
> I would use MatGetSubMatrix() to pull out the part of the matrix you care
> about and hand that
See this description from Jed
http://scicomp.stackexchange.com/questions/3298/appropriate-space-for-weak-solutions-to-an-elliptical-pde-with-mixed-inhomogeneo/3300#3300.
In a simpler way you could just scale your diagonal entries which are
1 at the moment with a value that is out of your interest
I would use MatGetSubMatrix() to pull out the part of the matrix you care
about and hand that matrix off to SLEPc.
Others prefer to remove the Dirichlet boundary value locations while doing
the finite element assembly, this way those locations never appear in the
matrix.
The end resul
Hello All,
As there isn't a SLEPc specific list, it was recommended that I bring my
question here. I am using SLEPc to solve a generalized eigenvalue
problem generated as part of the Finite Element Method, but am having
difficulty getting the diagonalizer to converge. I am worried that the
metho
