Thanks a lot. I appreciate your help. Have a nice evening. Rui
---- Original message ---- >Date: Thu, 7 May 2009 20:25:25 -0500 >From: Barry Smith <bsmith at mcs.anl.gov> >Subject: Re: ILUDropTolerance is not compatible with Mat re-ordering?? >To: ruiwang2 at illinois.edu, PETSc users list <petsc-users at mcs.anl.gov> > > > > PETSc has currently very little support for drop tolerance ILU. >ILU is the bane of any decent mathematicians existence. > > There isn't support for a reordering. > > Hong is actually working on much better, more general and more >complete ILUdt that should be ready in a couple of >months. (Yes, Hong has gone over to the dark side of mathematics :-)). > > Barry > >On May 7, 2009, at 8:19 PM, Rui Wang wrote: > >> Dear All, >> >> I am trying very hard to use PCILUSetUseDropTolerance() >> together with PCILUSetMatOrdering(), but it does not work, no matter >> what kind of MatOrderingType (RCM, ND...) i choose. The message I got: >> >> ------------------------------------------------------------- >> Note: The EXACT line numbers in the stack are not available, >> INSTEAD the line number of the start of the function >> is given. >> [0] MatILUDTFactor_SeqAIJ line 66 src/mat/impls/aij/seq/aijfact.c >> [0] MatILUDTFactor line 1362 src/mat/interface/matrix.c >> [0] PCSetUp_ILU line 568 src/sles/pc/impls/ilu/ilu.c >> [0] PCSetUp line 756 src/sles/pc/interface/precon.c >> [0] SLESSolve line 466 src/sles/interface/sles.c >> -------------------------------------------- >> [0]PETSC ERROR: unknownfunction() line 0 in unknown file >> [0] MPI Abort by user Aborting program ! >> [0] Aborting program! >> p0_32609: p4_error: : 59 >> ---------------------------------------------------------- >> >> I spent a lot of time on this and still cannot figure it out. >> >> Actually if I just use PCILUSetUseDropTolerance() itself, it works >> fine. Also, if I choose other ILU methods such as level-based ILU, >> PCILUSetMatOrdering() works perfectly with them. >> >> I wonder how to use ILUDropTolerance together with the reordering >> technique (such as RCM)? or they are not compatible? >> BTW, my PETSc version is 2.1.0. Is this because i am using this old >> version? >> >> Thanks a lot. >> >> Sincerely, >> Rui Wang >> >> >> >> >> -------------------------------------------------- >> Rui Wang >> Ph.D. Candidate >> Research Assistant and Predoctoral Fellow >> Department of Electrical and Computer Engineering >> University of Illinois at Urbana-Champaign >
