[petsc-users] suggestion for PCFieldSplitGetSubKSP

[Klaij, Christiaan]

I'm using PCFieldSplitGetSubKSP to access and modify the various
KSP's that occur in a Schur preconditioner. Now,
PCFieldSplitGetSubKSP returns two KSP's: one corresponding to A00
and one corresponding to the Schur complement.

However, in the LDU factorization, ksp(A00) occurs 4 times: in
the upper block, in the diagonal block, in the Schur complement
of the diagonal block and in the lower block.

So far, I'm using the runtime option -fieldsplit_1_inner to
access the ksp(A00) in the Schur complement, but it would make
sence if PCFieldSplitGetSubKSP returns all 5 KSP's involved. Or
is there another subroutine that I could call?

Chris


dr. ir. Christiaan Klaij
CFD Researcher
Research & Development
E mailto:C.Klaij at marin.nl
T +31 317 49 33 44


MARIN
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