Dear all,
For an eigenvalue solver, I was brainstorming on some ideas to solve
some linear systems of the form:
[A B] x1 = b1
[B C] x2 = b2
Where A and C are symmetric sparse but indefinite matrices due to some
shift operations. Namely, A = K-\sigmaM and
C = D/(\sigma)-E, where (K, M) and (D, E) are sparse symmetric stiffness
and mass matrix pairs of the structural and fluid domains, respectively.
However, B blocks are rather sparse coupling blocks and I was wondering
if I can use this property in order to solve this system with the
independent factorzations of A and C blocks either directly or
iteratively. Iterative path is more difficult I believe since the
matrices are indefinite.
I am open to any useful ideas that can make it work or suggestions to
kill this idea quickly.
Best regards and happy new year to all PETSc'ers.
Umut
