dolfin team mailing list archive

["Evan Lezar" <evanlezar@xxxxxxxxx>]

Thanks ... I am downloading paraview as we speak.

When I say plot the mesh - I mean plot the mesh and the function in
the same viper window?

:)

On Thu, May 22, 2008 at 11:43 AM, Anders Logg <logg@xxxxxxxxx> wrote:
> On Thu, May 22, 2008 at 11:34:54AM +0200, Evan Lezar wrote:
>> On Thu, May 22, 2008 at 12:42 AM, Anders Logg <logg@xxxxxxxxx> wrote:
>> > On Tue, May 20, 2008 at 09:43:54PM +0200, Evan Lezar wrote:
>> >> Hi there
>> >>
>> >> As an initial attempt, I am trying to use fenics to compute the resonant
>> >> modes of a rectangular waveguide - and as such I need to solve an
>> >> eigenvalue problem of the form  [A]x = lambda[B]x where x represents a
>> >> vector of coefficients of the basis functions used to calculate the
>> >> entries of the stiffness ([A]) and mass ([B]) matrices.
>> >>
>> >> It is easy to assemble the matrices, and I have solved the eigenvalue
>> >> problem using eigs() ... but now I have the calculated coefficients and
>> >> I would like to plot the weighted sum of the basis functions (the finite
>> >> element solution).
>> >>
>> >> Any help on the matter would be much appreciated.
>> >>
>> >> Thanks
>> >> Evan
>> >
>> > Are you doing this in Python or C++?
>> >
>> > If x is the vector, then you can do
>> >
>> >  Function u(mesh, x, a);
>> >
>> > where a is the form in C++.
>> >
>> > In Python, you need to do
>> >
>> >  Function u(element, mesh, x);
>> >
>> > where element is the FiniteElement you have used for the trial space.
>> >
>> > To plot the solution, just do
>> >
>> >  plot(u);
>> >
>> >
>>
>> Thanks for the reply - something is happening now at least :)
>>
>> Now that I have the function - how do I specify at which coordinates
>> it should be plotted?  At the moment, there are a couple of vectors
>> being plotted, but I would like a higher density.
>
> The builtin plotting (Viper) has very limited functionality (by
> intention). For more options, save to .pvd format and open in Paraview.
>
>> Also, is there a way to plot the mesh as well as the function in viper?
>
> Yes:
>
>  plot(mesh)
>
> :-)
>
> --
> Anders
> _______________________________________________
> DOLFIN-dev mailing list
> DOLFIN-dev@xxxxxxxxxx
> http://www.fenics.org/mailman/listinfo/dolfin-dev
>



-- 
visit http://randomestrandom.blogspot.com