On Fri, Nov 18, 2011 at 07:53, Thomas Witkowski < Thomas.Witkowski at tu-dresden.de> wrote:
> Defining the sparsity pattern is no problem. But is there any > documentation on MatFDColoringApply? The online function reference is quite > short and is not mentioned in the manuel. So, I have no real idea how this > is related to my question. You can find an example in snes/examples/tutorials/ex15.c The point is that it can compute the Schur complement by coloring. In your case, you can do subdomain solves independently, so you can compute S = K_PiPi - K_PiB inv(K_BB) K_BPi on each subdomain using Tmp = inv(K_BB) K_BPi (via MatMatSolve) Tmp2 = K_PiB * Tmp (via MatMatMult) S = K_PiPi - Tmp2 (via MatAXPY) You would then assemble the resulting independent matrices into the global matrix. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20111118/381afe1f/attachment.htm>
