Okay, thanks. I'll take a look. Dmitry.
On Mon, Feb 20, 2012 at 11:30 AM, Hui Zhang <mike.hui.zhang at hotmail.com>wrote: > For reference, my results are attached. > > asm1.txt for asm with 1 process, > asm2.txt for asm with 2 processes, > gasm1.txt for gasm with 1 process, (with the iteration numbers different > from others) > gasm2.txt for gasm with 2 processes > > > > > > > thank you, > Hui > > On Feb 20, 2012, at 3:06 PM, Dmitry Karpeev wrote: > > > > On Mon, Feb 20, 2012 at 12:59 AM, Hui Zhang <mike.hui.zhang at > hotmail.com>wrote: > >> >> On Feb 20, 2012, at 12:41 AM, Dmitry Karpeev wrote: >> >> >> >> On Sun, Feb 19, 2012 at 3:08 PM, Hui Zhang <mike.hui.zhang at >> hotmail.com>wrote: >> >>> I have a new problem: the results from ASM and GASM are different and it >>> seems >>> GASM has something wrong with SetModifySubMatrices. Numerical tests are >>> with >>> each subdomain supported only by one subdomain. There are no problems >>> when >>> I did not modify submatrices. But when I modify submatrices, there are >>> problems >>> with GASM but no problems with ASM. >>> >>> For example, I use two subdomains. In the first case each subdomain is >>> supported by >>> one processor and there seems no problem with GASM. But when I use run >>> my program >>> with only one proc. so that it supports both of the two subdomains, the >>> iteration >>> number is different from the first case and is much larger. On the >>> other hand >>> ASM has no such problem. >>> >> >> Are the solutions the same? >> What problem are you solving? >> >> >> Yes, the solutions are the same. That's why ASM gives the same results >> with one or >> two processors. But GASM did not. >> > Sorry, I wasn't clear: ASM and GASM produced different solutions in the > case of two domains per processor? > >> I'm solving the Helmholtz equation. Maybe >> I can prepare a simpler example to show this difference. >> > That would be helpful. > Thanks. > > Dmitry. > >> >> >> Dmitry. >> >>> >>> >>> On Feb 15, 2012, at 6:46 PM, Dmitry Karpeev wrote: >>> >>> You should be able to. >>> This behavior is the same as in PCASM, >>> except in GASM the matrices live on subcommunicators. >>> I am in transit right now, but I can take a closer look in Friday. >>> >>> Dmitry >>> >>> >>> >>> On Feb 15, 2012, at 8:07, Hui Zhang <mike.hui.zhang at hotmail.com> wrote: >>> >>> On Feb 15, 2012, at 11:19 AM, Hui Zhang wrote: >>> >>> Hi Dmitry, >>> >>> thanks a lot! Currently, I'm not using ISColoring. Just comes another >>> question >>> on PCGASMSetModifySubMatrices(). The user provided function has the >>> prototype >>> >>> func (PC pc,PetscInt nsub,IS *row,IS *col,Mat *submat,void *ctx); >>> >>> I think the coloumns from the parameter 'col' are always the same as >>> the rows >>> from the parameter 'row'. Because PCGASMSetLocalSubdomains() only >>> accepts >>> index sets but not rows and columns. Has I misunderstood something? >>> >>> >>> As I tested, the row and col are always the same. >>> >>> I have a new question. Am I allowed to SetLocalToGlobalMapping() for the >>> submat's >>> in the above func()? >>> >>> thanks, >>> Hui >>> >>> >>> thanks, >>> Hui >>> >>> >>> On Feb 11, 2012, at 3:36 PM, Dmitry Karpeev wrote: >>> >>> Yes, that's right. >>> There is no good way to help the user assemble the subdomains at the >>> moment beyond the 2D stuff. >>> It is expected that they are generated from mesh subdomains. >>> Each IS does carry the subdomains subcomm. >>> >>> There is ISColoringToList() that is supposed to convert a "coloring" of >>> indices to an array of ISs, >>> each having the indices with the same color and the subcomm that >>> supports that color. It is >>> largely untested, though. You could try using it and give us feedback >>> on any problems you encounter. >>> >>> Dmitry. >>> >>> >>> On Sat, Feb 11, 2012 at 6:06 AM, Hui Zhang <<mike.hui.zhang at hotmail.com> >>> mike.hui.zhang at hotmail.com> wrote: >>> >>>> About PCGASMSetLocalSubdomains(), in the case of one subdomain >>>> supported by >>>> multiple processors, shall I always create the arguments 'is[s]' and >>>> 'is_local[s]' >>>> in a subcommunicator consisting of processors supporting the subdomain >>>> 's'? >>>> >>>> The source code of PCGASMCreateSubdomains2D() seemingly does so. >>>> >>>> Thanks, >>>> Hui >>>> >>>> >>> >>> >>> >>> >> >> > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120220/a1a9b1be/attachment.htm>
