Yes
On Mon, Nov 19, 2012 at 9:54 AM, Thomas Witkowski < thomas.witkowski at tu-dresden.de> wrote: > Jed: To you think that I can write a work-around in just using > PetscOptionsInsertString before KSPSetUp with some settings that I don't > will use later but which would make KSPSetUp on the corresponding solver > object cheap? > > Thomas > > Am 19.11.2012 09:48, schrieb Jed Brown: > > Unfortunately, options are currently the only way to avoid the initial > setup. We could add a special setup routine to the PCFieldSplit interface > that you could call, but there are lots of other PCs that you sometimes > want to reconfigure after "partial setup". I've been unhappy with this for > years, but have not found a general and maintainable way to support, and > configuration via options is a better approach most of the time. > > > On Mon, Nov 19, 2012 at 2:29 AM, Thomas Witkowski < > thomas.witkowski at tu-dresden.de> wrote: > >> In the implementation of my Navier-Stokes solver, I initialize the >> PCFieldSplit preconditioner in my source code (thus not on the command >> line) in the following way: >> >> PCSetType(pc, PCFIELDSPLIT); >> PCFieldSplitSetType(pc, PC_COMPOSITE_SCHUR); >> PCFieldSplitSetSchurFactType(pc, PC_FIELDSPLIT_SCHUR_FACT_FULL); >> ... >> KSPSetUp(ksp); >> KSP *subKsp; >> PetscInt nSubKsp; >> PCFieldSplitGetSubKSP(pc, &nSubKsp, &subKsp); >> KSP kspVelocity = subKsp[0]; >> KSP kspSchur = subKsp[1]; >> ... >> >> And then kspVelocity and kspSchur are filled with appropriate options. >> The point is now, that to get the sub solver objects, I have to run >> KSPSetUp before. In this case, the sub solver objects are also initialized >> with some predefined options (block jacobi ILU), which I don't need and >> what takes some time and memory. Is there any other way to get the sub >> solver objects before and to initialize than the outer solver correctly >> with the inner solver I have specified? >> >> >> Thomas >> > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20121119/3c29c5ed/attachment-0001.html>
