On Sun, Feb 26, 2012 at 10:48 AM, Max Rudolph <maxwellr at gmail.com> wrote:
> MPIAIJ and SEQQIJ matrices are subtypes of the AIJ matrix type. Looking at > that table, you should be able to use any of the PCs that supports AIJ and > has an X under 'parallel'. Max is correct. For instance, the most popular general purpose parallel solver is ASM (Additive Schwarz Method), which then has a sequential subsolver for each block, which defaults to ILU. Matt > Max > > > On Sun, Feb 26, 2012 at 8:16 AM, Aron Roland <aaronroland at gmx.de> wrote: > >> Dear All, >> >> I hope somebody can help us on this or give at least some clearance. >> >> We have just included PETSc as an solver for our sparse matrix evolving >> from an unstructured mesh advection scheme. >> >> The problem is that we are using the mpiaij matrix type, since our matrix >> is naturally sparse. However it seems that PETSc has no PC for this, except >> the PCSOR, which showed to be not very effective for our problem. >> >> All others give the error msg. of the mail subject, where XXX are the >> different PC tried. >> >> The manual is a bit diffuse on this e.g. >> >> http://www.mcs.anl.gov/petsc/**documentation/**linearsolvertable.html<http://www.mcs.anl.gov/petsc/documentation/linearsolvertable.html> >> >> it is claimed that certain PC's are running on aij matrices ... but these >> are to be defined either as seq. or parallel (mpiaij) matrices. Moreover in >> the above mentioned list are two columns parallel/seriel, what is the >> intention of parallel capability when not applicable to matrices stored >> within the parallel mpiaij framework. >> >> I guess we just not understanding the concept or have some other >> difficulties of understanding of all this. >> >> Any comments help is welcome >> >> Aron >> > > -- 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/20120226/bd581795/attachment-0001.htm>
