Thank you very much, this seems to work well.
I have another question linked to this which is probably a bit basic so
I apologize.
At the end of my program, I want to destroy all the petsc objects. I
start by destroying the matrixes, then the ksp and pc objects similarly
to how it's done in the examples. However I get an error when attempting
to destroy the KSP and PC objects :
[0]PETSC ERROR: Invalid argument
[0]PETSC ERROR: Wrong type of object: Parameter # 1
I've tried switching the order around, but I still get the same errors.
And if I don't destroy these objects I get a memory leak, which I'd like
to avoid.
My question is I don't really understand when and how I'm supposed to
destroy the KSP and PC objects?
Thanks again,
Best regards,
Perceval,
You can do this directly in PETSc. Create a KSP object with PREONLY and
PCCHOLESKY (or just a PC object). Then call KSPSetUp (or PCSetUp) and extract
the factored matrix with PCFactorGetMatrix(). Then call MatGetInertia() on the
factored matrix. Repeat this for each value of E.
I guess it can be even shorter if you call MatCholeskyFactor() directly.
Jose
El 24 mar 2020, a las 11:07, Perceval Desforges
<perceval.desfor...@polytechnique.edu> escribió:
Dear petsc developers,
I am interested in calculating the inertias of matrixes. Specifically, for a certain matrix A, and for different real numbers E, I want to calculate the inertias of (A - E * I), in order to get the number of eigenvalues less than E.
In order to do this I have been setting up a slepc EPS object with spectrum
slicing, and using EPSKrylovSchurGetInertias. I realize this is a bit
convoluted, and was wondering if there is a better way to do this?
Best regards,
Perceval,
P.S. my last email seems to not have been sent (I couldn't find it in the
archives) so I am trying again...
