On Tue, Jan 6, 2009 at 1:43 PM, Yujie <recrusader at gmail.com> wrote:
> Dear Matthew: > > Two processors are used. The matrix dimension is 105*108; > > MatGetOwnershipRange() > > proc1: 0->56 > > proc2: 56->105 > > Mat->camp.rstart; Mat->cmap.rend > > proc1: 0->54 > > proc2: 54->108 > > MatGetLocalSize() > > proc1: row 56 col 54 > > porc2: row 49 col 54 > > MatDenseGetLocalMatrix() > > proc1: 56*108 > > proc2: 49*108 > > Since PETSc matrices are all stored row-wise, even if columns are assigned to one process for the other, the storage is divided by row. This GetLocalMatrix() returns all the rows associated with a given process. Matt > thanks. > > Yujie > > On Tue, Jan 6, 2009 at 11:33 AM, Matthew Knepley <knepley at gmail.com>wrote: > >> On Tue, Jan 6, 2009 at 11:52 AM, Yujie <recrusader at gmail.com> wrote: >> >>> Dear PETSc developers: >>> >>> I am trying to use MatGetArray() and MatSetValues() to combine several >>> MPIDense matrices into one matrix. At the beginning, I use >>> >>> MatGetOwnershipRange() and Mat->camp.rstart; Mat->cmap.rend (2.3.3-p8 >>> version) to get the start, end row and column. I can calculate the local >>> rows and columns. >>> >>> I also use MatGetLocalSize() to confirm the accuracy. However, I always >>> find some data loses in the combined matrix. >>> >>> And then, I try to use MatDenseGetLocalMatrix() to get the lcoal matrix >>> and output it. I find column information by MatGetLocalSize() is not >>> consistent with by MatDenseGetLocalMatrix(), is it bug? could you give me >>> some advice? thanks a lot. >>> >> What information? >> >> Matt >> >> >>> Regards, >>> >>> Yujie >>> >> -- >> 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 >> > > -- 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/20090106/5dbada4f/attachment.htm>
