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<div class="moz-cite-prefix">Hello,<br>
<br>
Thank for your answer, I'll explain my trouble:<br>
<br>
My problem is that the BC Neumann leads to wrong result.<br>
<br>
With Dirichlet BC, I get:<br>
-------------------------------<br>
<br>
> ./ex12 -run_type full -refinement_limit 0.0 -bc_type
dirichlet -interpolate 0 -petscspace_order 1 -show_initial
-show_solution -dm_plex_print_fem 1<br>
...<br>
...<br>
Solution<br>
Vec Object:potential 1 MPI processes<br>
type: seq<br>
0.5<br>
<br>
This result is correct.<br>
<br>
With Neuman BC, I get:<br>
--------------------------------<br>
<br>
> ./ex12 -run_type full -refinement_limit 0.0 -bc_type
neumann -interpolate 1 -petscspace_order 1 -show_initial
-dm_plex_print_fem 1 -show_solution -bd_petscspace_order 1
-snes_linesearch_monitor -snes_monitor
-ksp_monitor_true_residual -snes_converged_reason
-ksp_converged_reason<br>
....<br>
....<br>
<br>
<br>
Solution<br>
Vec Object:potential 1 MPI processes<br>
type: seq<br>
-0.75<br>
-0.583333<br>
0.0833333<br>
-0.583333<br>
-0.333333<br>
0.416667<br>
0.0833333<br>
0.416667<br>
1.25<br>
<br>
<br>
That is not the values of the solution x*x+y*y.<br>
<br>
<br>
I tried many ksp options. <br>
Moreover, the neumann BC with "-run_type full" is not cover in the
list <a moz-do-not-send="true"
href="https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257">https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257</a><br>
<br>
Do you know what is wrong ?<br>
<br>
Thanks,<br>
<br>
Olivier Bonnefon<br>
<br>
On 10/31/2014 06:50 PM, Matthew Knepley wrote:<br>
</div>
<blockquote
cite="mid:CAMYG4GkO5fbVe1_ALSdRE892WtQtyxMS-aDxpN0ryZNf+WU4KA@mail.gmail.com"
type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">On Fri, Oct 31, 2014 at 10:43 AM,
Olivier Bonnefon <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:olivier.bonnefon@avignon.inra.fr"
target="_blank">olivier.bonnefon@avignon.inra.fr</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">Hello,<br>
<br>
I'm working on the snes/examples/tutorial/ex12 version
3.5.2.<br>
<br>
I didn't succed to run the simplest case with Neumann BC:<br>
<br>
./ex12 -run_type full -refinement_limit 0.0 -bc_type
neumann -interpolate 1 -petscspace_order 1 -show_initial
-dm_plex_print_fem 1 -show_solution -bd_petscspace_order 1
-snes_linesearch_monitor -snes_monitor
-ksp_monitor_true_residual -snes_converged_reason
-ksp_converged_reason<br>
<br>
This leads to dofs negatives values.<br>
</blockquote>
<div><br>
</div>
<div>I do not understand what you mean. Please always mail
the full error message.</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">Do
you know the options to get a correct result with Neumann
BC ?<br>
</blockquote>
<div><br>
</div>
<div>There are some tests here:</div>
<div><br>
</div>
<div><a moz-do-not-send="true"
href="https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257">https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257</a><br>
</div>
<div><br>
</div>
<div> Matt</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">Regards,<br>
Olivier Bonnefon<br>
<br>
</blockquote>
</div>
<br>
<br clear="all">
<div><br>
</div>
-- <br>
What most experimenters take for granted before they begin
their experiments is infinitely more interesting than any
results to which their experiments lead.<br>
-- Norbert Wiener
</div>
</div>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Olivier Bonnefon
INRA PACA-Avignon, Unité BioSP
Tel: +33 (0)4 32 72 21 58</pre>
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