Yes, this usually works as long as the preconditioner for A is stable on the non-null subspace. On Jan 9, 2012 5:43 PM, "Geoffrey Irving" <irving at naml.us> wrote:
> Hello, > > I have a matrix A and an orthogonal projection operator P onto a > fairly large (but sparse) linear subspace. I want to solve the system > > PAPx = Pb > > If set up a MatNullSpace object with MatNullSpaceSetFunction, with KSP > solve the system I want even if A is nonsingular? > > Thanks, > Geoffrey > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120109/31302926/attachment.htm>
