[petsc-users] (no subject)

Kristen Eisenberg kristen.eisenberg at yahoo.com
Mon Sep 5 16:08:16 CDT 2011


[petsc-users] SLEPc generalized eigenvalue problem question?


I create 2 matrices using:

MatCreateSeqDense(PETSC_COMM_SELF, n, n, Ka, &A);
MatCreateSeqDense(PETSC_COMM_SELF, n, n, Kb, &B);

These matrices are 99% zeros ( 16,016,004 entries and 18660 non-zeros).
They are symmetric and real.  Their tri-diagonal elements are non-zero plus
a few other entries.

I tried to use ex7 for the generalized eigenvalue problem:

./ex7.exe -f1 k.dat -f2 m.dat -eps_gen_hermitian -eps_smallest_real > x.out
2>&1

without specifying an EPS and get:

Generalized eigenproblem stored in file.

Reading REAL matrices from binary files...
Number of iterations of the method: 500
Number of linear iterations of the method: 4009
Solution method: krylovschur

Number of requested eigenvalues: 1
Stopping condition: tol=1e-07, maxit=500
Number of converged approximate eigenpairs: 0

Is krylovschur inappropriate for this problem or have I set up the problem
incorrectly by using   MatCreateSeqDense(...) to create the matrix input
files in PETSc binary form?

Kristen Eisenberg
Billige Flüge
Marketing GmbH
Emanuelstr. 3,
10317 Berlin
Deutschland
Telefon: +49 (33)
5310967
Email:
utebachmeier at gmail.com
Site:
http://flug.airego.de - Billige Flüge vergleichen
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110905/2efb7442/attachment.htm>


More information about the petsc-users mailing list