dolfin team mailing list archive

[Bing Jian <bjian@xxxxxxxxxxxx>]

On Tue, 27 Jul 2004, Johan Jansson wrote:

> On Mon, Jul 26, 2004 at 05:37:04PM -0400, Bing Jian wrote:
> >
> > Hi, Dear Dolfin folks,
> >
> >    I just tried the poisson and poisson-multigrid in
> > /src/demo/solvers.  Here are some notes, questions
> > and suggestions:
> >
> >    (1) I note there are already precompiled
> > executables in each directory. However, when I run
> > those binary programs on my Mandrake, it gives segmentation
> > fault after the iterations converge.
> >
> >    (2) So I just did "make clean" and "make" again. Since
> > I copied these 2 directories out of the installation position,
> > when I did make, I need to modify the prefix directory for
> > configuration. I don't know if it would be better to organize the
> > build process by using CMake (www.cmake.org), like what
> > itk (www.itk.org) does.
> >
>
> Are you using the version from Anders' thesis? I think it would be
> better to download from the web:
>
> http://www.phi.chalmers.se/pub/software/dolfin/v0.4/
>
> or use CVS (code not always guaranteed to work):
>
> cvs -d :pserver:anonymous@xxxxxxxxxxxxxxxxxxxxxx:/cvs checkout -P dolfin
>
> I think the problem with your prefix directory is solved by running
> "./configure" from the DOLFIN root.
>

  Actually, that's what I did. I used cvs to check out the dolfin
and did './configure','make','make install'

>
> >    (3) After re-building, I can run the solvers successfully
> > and generate the poisson.m. I think it's very fast! So great!
> > For visualization, in matlab with pde toolbox, I just use
> > pdesurf('points','cells','u') after loading poisson.m to
> > visualize the solution,  is it right? Seems the solution
> > solved by multi-grid solver is smoother than another one,
> > and its error is smaller (0.13529)
>
> The Poisson module is 3D, and I don't think pde toolbox can display
> such solutions/meshes. If you try the convection diffusion module,
> then you can just load convdiff.m and plot: pdesurf(points, cells,
> u{5}) where the cell number 5 is time point number 5.
>
> For the vector wave module, you can load wavevector.m and then plot:
> pdesurf(points, cells, u{50}(:, 1)) for component 1 and
> pdesurf(points, cells, u{50}(:, 2)) for component 2 at time point 50.
>
> >
> >    (4) As for the mesh, how to generate the mesh.xml.gz,
> > using matlab or gid?  If the domain of the problem is
> > a rectangle, can I just use regular mesh? And how to
> > store the vectorized solution u into 2d array?
> >
>
> I haven't looked much at the mesh part, but it seems the scripts in
> "src/utils/" will do what you need. You have "writeinp.m" which
> converts from matlab to INP, and then "inp2xml". Perhaps there are
> even better ways.
>
>   Johan
>
>

   Yes, I found those programs in src/utils. But I don't understand,
is there any readme file for this part? Thanks!


--
Best wishes,
Bing Jian
bjian@xxxxxxxxxxxx