[Nek5000-users] Periodic BC & Genmap issue

[nek5000-users at lists.mcs.anl.gov]

Hi Michael,

It looks like the issue is related to the mesh and to tolerances.
It appears to me that the periodic faces are not congruent - nearly
so, but not 100%.

I've changed my version of genmap to make the tolerance in the 
periodicity check reflect the user-prompted value.  I'm not yet 
commiting this to the repo because I need to think more about the 
consequences.  However, the attached code does work when you input 
".1" for the tolerance prompt - and it flags an error when you put 
in .01 or smaller.  Try diff'g this against your current version 
to see the change.

Paul

PS - rather than attaching, I'm placing in 
www.mcs.anl.gov/~fischer/genmap.f.gz


On Mon, 21 Jun 2010, nek5000-users at lists.mcs.anl.gov wrote:

> Hi,
>
> I am running into an error when trying to use genmap. I believe it has to do with the periodic boundary conditions I have set up. I have checked the elements, and faces and indeed they are given correctly. This leads me to believe that there may be an issue with genmap. I have attached the rea file. This was to test the periodic faces for this geometry. The output is shown below, thanks for any help with this.
>
> - Michael M.
>
> Here is the output:
>
> test
> Input mesh tolerance (default 0.2):
> NOTE: smaller is better, but generous is more forgiving for bad meshes.
> .2
> reading .rea file data ...
> start locglob_lexico: 8 60 480 0.20000000000000001
> locglob: 1 1 480
> locglob: 2 27 480
> locglob: 3 42 480
> locglob: 1 168 480
> locglob: 2 168 480
> locglob: 3 168 480
> locglob: 1 168 480
> locglob: 2 168 480
> locglob: 3 168 480
> done locglob_lexico: 168 168 480 4
> start periodic vtx: 60 168
> 1 3 5 3 3.66325334E-04 1 shift
> 3 4 4 Matrix: x0
> 1 x0 1.7389E-03 2.8363E-03 2.8363E-03 1.7389E-03
> 2 x0 -6.9998E-02 7.0969E-02 6.9026E-02 -6.9998E-02
> 3 x0 2.0879E-02 2.0879E-02 -2.0937E-02 -2.0821E-02
> 4 x0 8.3935E-03 8.0685E-03 -2.4856E-02 8.3935E-03
> 1 4 4 Matrix: x1
> 1 x1 1.7389E-03 1.7389E-03 2.8351E-03 2.8351E-03
> 2 x1 -7.0107E-02 -7.0107E-02 6.8930E-02 7.1286E-02
> 3 x1 2.0876E-02 -2.0824E-02 -2.0927E-02 2.0876E-02
> 4 x1 8.3867E-03 8.3867E-03 -2.4834E-02 8.0608E-03
> 3 4 4 Matrix: z0
> 1 z0 1.7389E-03 2.8363E-03 2.8363E-03 1.7389E-03
> 2 z0 -1.2500E+00 -1.1090E+00 -1.1110E+00 -1.2500E+00
> 3 z0 0.0000E+00 0.0000E+00 -4.1816E-02 -4.1700E-02
> 4 z0 -5.0620E-01 -5.0653E-01 -5.3945E-01 -5.0620E-01
> 1 4 4 Matrix: z1
> 1 z1 1.7389E-03 1.7389E-03 2.8351E-03 2.8351E-03
> 2 z1 -1.2500E+00 -1.2500E+00 -1.1110E+00 -1.1086E+00
> 3 z1 0.0000E+00 -4.1700E-02 -4.1803E-02 0.0000E+00
> 4 z1 4.9380E-01 4.9380E-01 4.6058E-01 4.9347E-01
> 3 4 3 1.00000000E-03 7.09692500E-02 abort: FACE MATCH FAIL
> 1 3 5 7.09692500E-05 3.66325334E-04 abort: FACE MATCH FAIL
>
>