[Getdp] some warning message

[Ji, Lin]

Dear Christophe,
      Thanks for the information. By enforcing Dimension 3, the false
warning dissapear. But there still remain two minor issues.
      First, having zero value at some surface point is not correct in some
case. How can we output the true solution value on the surface into the same
file as the solution in the domain? Because eventually, I want to import the
data into a matrix on regular grid points where there is no distinction
between surface and interior.
     Second, in the case of a vector solution, I get only one zero value
instead of 3 zero values on some surface element. This caused a little
trouble when I tried to import the data (TimeTable format) into a matlab
matrix because my little importing program counts on the three components of
a vector. Although it can be worked around, it would be better to keep the
format uniform for every point. The following is part of the output to show
what I mean by only one zero value for some point:

 58 0.05900000000000005  -6 -4.2 1.2  -35.57680985887268
0.8073098794431409 -10.60569408924594
59 0.06000000000000005  -6 -4.2
1.2  -19.60545899750656 -0.1722236169587627 -43.32303149432153
0 0.001  -6 -4.2 1.35  0
1 0.002  -6 -4.2 1.35  0
2 0.003  -6 -4.2 1.35  0
3 0.004  -6 -4.2 1.35  0

By the way, does the new version of getdp have the matrix format for data on
regular grid points that can be readily used in matlab? Thanks a lot.

Lin Ji
Department of Mathematics, Amos Eaton 407
Rensselaer Polytechnic Institute
Troy, NY 12180
----- Original Message -----
From: "Christophe Geuzaine" <geuzaine at acm.caltech.edu>
To: "Lin Ji" <jil at rpi.edu>
Cc: <getdp at geuz.org>
Sent: Wednesday, June 04, 2003 2:04 AM
Subject: Re: [Getdp] some warning message


> Lin Ji wrote:
> > Dear Christophe,
> >      I got the following warning message when I postprocess the solution
> > to the elastic wave equation to generate the timetable data. Can you
tell
> > me what it means?
>
> It's not a big deal: you're probably trying to evaluate a quantity
> outside the mesh, or on an element whose dimension is smaller than the
> dimension of the problem you're solving (e.g. on a surface element for a
> 3D problem). You'll just end up with 0 as the value at that evaluation
> point.
>
> Note that you can try to force the dimension in the search algorithm by
> adding "Dimension 3" (in 3D), "Dimension 2" (in 2D), etc., to the
> options of the PostOperation. This should eliminate the "false positives".
>
> Cheers,
>
> Christophe
>
> > Solving the elastic wave equation seems to be fine. It
> > converges at each time step. Thanks
> >
> > --- output  ----
> > /personal/research/proj_rep/wave3D-EL (4) ../../getdp-0.86.0/getdp wave
> > -pos -msh box3.msh
> > Loading   : Problem definition 'wave.pro'
> > Loading   : Problem definition 'func3.pro'
> > Loading   : Problem definition 'order1.pro'
> > Info      : Available PostOperations
> > (1) u_msh
> > (2) u_ttable
> > Choice: 2
> > Info      : Selected Resolution 'Wave'
> > Loading   : Geometric data 'box3.msh'
> > Info      : System 'A' : Real
> > P r e - P r o c e s s i n g . . .
> > Loading   : Pre-Processing data 'wave.pre'
> > Resources : cpu 2.200000 s / mem 0 kb
> > E n d   P r e - P r o c e s s i n g
> > P o s t - P r o c e s s i n g . . .
> > Loading   : Processing data 'wave.res'
> > Info      : Selected PostProcessing 'Wave'
> > Info      : Selected Mesh 'box3.msh'
> > Operation : PostOperation 1/1
> >           > 'u_ttable.pos'
> > Info      : Initializing rapid search grid 20x20x20
> > Warning   : Zero determinant in 'xyz2uvwInAnElement'
> > Warning   : Maximum number of iterations exceeded in xyz2uvwInAnElement
> > Warning   : Zero determinant in 'xyz2uvwInAnElement'
> > Resources : cpu 208.160000 s / mem 0 kb
> > E n d   P o s t - P r o c e s s i n g
> > E n d
> >
> > Lin Ji
> > Dept. of Math., Amos Eaton
> > Rensselaer Polytechnic Institute
> > 110 8th Street
> > Troy, New York 12180-3590
> >
> > Phone: 518-276,8377 (work)
> >
> > _______________________________________________
> > getdp mailing list
> > getdp at geuz.org
> > http://www.geuz.org/mailman/listinfo/getdp
> >
> >
>
> --
> Christophe A. Geuzaine
> Applied and Computational Mathematics, Caltech
> geuzaine at acm.caltech.edu - http://geuz.org
>