[petsc-users] unsure about ex19 test results

[Dominik Szczerba]

Nice catch, thanks, no, I overlooked the extra options when reverse
engineering the test from the makefiles. Now I get identical output.

Thanks,
Dominik

On Mon, Dec 5, 2011 at 3:24 PM, Matthew Knepley <knepley at gmail.com> wrote:
> On Mon, Dec 5, 2011 at 8:17 AM, Dominik Szczerba <dominik at itis.ethz.ch>
> wrote:
>>
>> I am on a Cray system, where I have configured and built petsc 3.2 p5
>> myself, only using the vendor provided mpi, all the other packages
>> (parmetis, hypre, mumps) are built with --download-package. "Make ...
>> test" does not work here to verify the correct build because users do
>> not have access to mpiexec. So I do the test by hand, and I am unsure
>> about what I am getting. When executing the test ex19 with the
>> system's scheduler I get this output:
>>
>> lid velocity = 0.0204082, prandtl # = 1, grashof # = 1
>> Number of Newton iterations = 2
>> lid velocity = 0.0204082, prandtl # = 1, grashof # = 1
>> Number of Newton iterations = 2
>>
>> It's quite different from the expected output in ex19_1.testout:
>>
>> lid velocity = 0.0016, prandtl # = 1, grashof # = 1
>> Number of Newton iterations = 2
>> lid velocity = 0.0016, prandtl # = 1, grashof # = 1
>> Number of Newton iterations = 2
>
>
> Are you running with the right options?  -dmmg_nlevels 4 -snes_monitor_short
>
>   Matt
>
>>
>> Does it mean that I have screwed up the build somehow, or is this
>> somehow the effect of the batching system, or just numerical
>> uncertainty due to the parallel computation? Note: I get the same
>> result with 1 and a few MPI processes.
>>
>> Many thanks for any ideas.
>>
>> Dominik
>
>
>
>
> --
> 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