> Message: 6 > Date: Mon, 23 Aug 2010 18:40:34 -0500 > From: Barry Smith <bsmith at mcs.anl.gov> > Subject: Re: [petsc-dev] Problem with conjugate gradient solver > To: For users of the development version of PETSc > <petsc-dev at mcs.anl.gov> > Message-ID: <6432610F-F243-4C9C-AB6A-0944221AE18D at mcs.anl.gov> > Content-Type: text/plain; charset=us-ascii > > > On Aug 23, 2010, at 2:31 PM, Anush Krishnan wrote: > > > Hi, > > > > I was trying to compile and run the example file > $PETSC_DIR/src/ksp/pc/examples/tutorials/ex3.c, which demonstrates PETSc's > preconditioned conjugate gradient solver for a system of linear equations. > After compiling, running make runex3 is supposed to throw up the error > "Divergence because of indefinite preconditioner" and running make runex3_pd > is supposed to work and give the correct solution. But instead I get the > error "Other kind of divergence: this should not happen." for the latter. Is > there some bug in the code, or are there any other options that need to be > set? > > Hmm, worked for me. > > Please hg pull; hg update then rebuild PETSc and run the make runex3 > runex3_pd again and send the output. I added to that example what reason it > did have to maybe help determine the problem. Or you can run the example > with the options given in the makefile and also the option > -ksp_converged_reason >
I've attached the outputs I got with runex3 and runex3_pd (1 and 2 respectively. I commented out the statements after the execute commands to prevent deletion of the generated output files). This was on revision 16788. Thanks, Anush > > > Barry > > > > > Thanks, > > Anush > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100824/08fcae5b/attachment.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: ex3_inode.out_1 Type: application/octet-stream Size: 6684 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100824/08fcae5b/attachment.obj> -------------- next part -------------- A non-text attachment was scrubbed... Name: ex3_inode.out_2 Type: application/octet-stream Size: 9113 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100824/08fcae5b/attachment-0001.obj> -------------- next part -------------- A non-text attachment was scrubbed... Name: ex3.tmp_1 Type: application/octet-stream Size: 6684 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100824/08fcae5b/attachment-0002.obj> -------------- next part -------------- A non-text attachment was scrubbed... Name: ex3.tmp_2 Type: application/octet-stream Size: 9113 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100824/08fcae5b/attachment-0003.obj>
