On Thu, Jun 7, 2012 at 3:35 PM, TAY wee-beng <zonexo at gmail.com> wrote:
> > On 7/6/2012 4:33 AM, Jed Brown wrote: > > On Wed, Jun 6, 2012 at 4:21 PM, TAY wee-beng <zonexo at gmail.com> wrote: > >> *call PCMGSetLevels(pc,mg_lvl,MPI_COMM_WORLD,ierr)* > > > The third arguments is an array of length mg_lvl, not a single > communicator. You can pass PETSC_NULL_OBJECT just like the man page says to > use the default. > > >> >> I changed but the same Segmentation still occurs: > Look, programming is a skill. It demands you learn to use certain tools. A message like "Segmentation still occurs" is USELESS since we are not looking at your code or running it. Sending in a stack trace from gdb is much more informative and means you will get help sooner. Matt > call KSPCreate(MPI_COMM_WORLD,ksp,ierr) > > call KSPGetPC(ksp,pc,ierr) > > call PCSetType(pc_uv,PCMG,ierr) > > mg_lvl = 1 (or 2) > > call PCMGSetLevels(pc,mg_lvl,PETSC_NULL_OBJECT,ierr) > > call > DMDACreate2d(MPI_COMM_WORLD,DMDA_BOUNDARY_NONE,DMDA_BOUNDARY_NONE,DMDA_STENCIL_STAR,size_x,size_y,1,num_procs,i1,i1,PETSC_NULL_INTEGER,PETSC_NULL_INTEGER,da,ierr) > > ... > > Btw, I tried to look at > http://www.mcs.anl.gov/petsc/petsc-current/src/ksp/ksp/examples/tutorials/ex42.c.htmlbut > I think there's some error in the page formatting. > > >> However, I get the error: >> >> Caught signal number 11 SEGV: Segmentation Violation, probably memory >> access out of range >> >> after calling *PCMGSetLevels* >> >> What's the problem? Is there any examples which I can follow? >> > > I believe the other examples that use this routine are in C or just tests > (not tutorial-style) examples. > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120607/7644a797/attachment.html>
