[Trilinos-Users] SolverManagers does not initialize for some reason

[Baker, Christopher G.]

Hello Mehmet,

This poorly-phrased error indicates that the eigenanalysis computed for the initial vectors was unsuccessful. The LOBPCG solver operates by using the initial vectors (those passed to Eigenproblem::setInitVec()) to project the eigenvalue problem to a small, dense problem that is solved to generate initial estimates of the solution. In this case, the initial problem could not be solved, apparently because the projection of the B matrix (from the original problem A*x=B*x*lambda) was not symmetric positive definite. This is either because the matrix B is not symmetric positive definite (a requirement for using both the BlockDavidson and LOBPCG solvers) or because the initial multivector did not have full column rank (perhaps it was initialized to all zeros or all ones? Try randomizing it.)

Chris


On 5/22/10 4:42 PM, "Mehmet Salih YILDIRIM" <linux at isadamlari.org> wrote:

Hi,
We are trying to deal with generalized eigenproblems.
we tried all of the solver managers provided within the anasazi package but we got these[1] errors for LOBPCG and similar errors for others. We tried to solve this issues but we couldn't find exact problem. Any help will be appreciated.

[1]:
Anasazi::LOBPCG::initialize(): Initial Ritz analysis did not produce enough Ritz pairs to initialize algorithm.
Anasazi::LOBPCGSolMgr::Solve() returning Unconverged with no solutions.


Thanks in advance.