Hello,
Thank for your answer, I'll explain my trouble:
My problem is that the BC Neumann leads to wrong result.
With Dirichlet BC, I get:
-------------------------------
> ./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
...
...
Solution
Vec Object:potential 1 MPI processes
type: seq
0.5
This result is correct.
With Neuman BC, I get:
--------------------------------
> ./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
....
....
Solution
Vec Object:potential 1 MPI processes
type: seq
-0.75
-0.583333
0.0833333
-0.583333
-0.333333
0.416667
0.0833333
0.416667
1.25
That is not the values of the solution x*x+y*y.
I tried many ksp options.
Moreover, the neumann BC with "-run_type full" is not cover in the list
https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257
Do you know what is wrong ?
Thanks,
Olivier Bonnefon
On 10/31/2014 06:50 PM, Matthew Knepley wrote:
On Fri, Oct 31, 2014 at 10:43 AM, Olivier Bonnefon
<[email protected]
<mailto:[email protected]>> wrote:
Hello,
I'm working on the snes/examples/tutorial/ex12 version 3.5.2.
I didn't succed to run the simplest case with Neumann BC:
./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
This leads to dofs negatives values.
I do not understand what you mean. Please always mail the full error
message.
Do you know the options to get a correct result with Neumann BC ?
There are some tests here:
https://bitbucket.org/petsc/petsc/src/fced3c3f9e703542693913793d15321603e40fe6/config/builder.py?at=master#cl-257
Matt
Regards,
Olivier Bonnefon
--
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
--
Olivier Bonnefon
INRA PACA-Avignon, Unité BioSP
Tel: +33 (0)4 32 72 21 58
