[Trilinos-Users] Solver Managers unconverge

[Mehmet Salih YILDIRIM]

Hello!

Recently, we'd been trying to implement an image segmentation algorithm
sm-ncut <http://www.cs.berkeley.edu/~malik/papers/SM-ncut.pdf> using
trilinos. We decided to use trilinos because the implementation was supposed
to be a distributed one. But we encountered some problems. They are:

We have to calculate the eigenvector corresponding to second smallest
eigenvalue for a large sparse matrix, but all of the eigensolvers in Anasazi
return Anasazi::Unconverged upon calling the solve() function. We are trying
to solve the generalized eigenproblem A*x = lambda*B*x where A and B are
hermitian and B is a diagonal matrix with all positive elements. (I think it
means positive definitive maybe.)

After solving the problem, we need to collect (gather?) this eigenvector on
the root node. (with pid = 0) But in the Anasazi documentation, nothing
about the map of resulting eigenvectors is mentioned. How may i process this
resulting eigenvector locally on the root node?

Ps: Sorry, I sent this mail as a response of a previous mail accidentally.
That is why I am resending as a new topic.

Any help will be appreciated.
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