[Gmsh] Visualization of high order FE

[Christophe Geuzaine]

Hi Gonçalo - Everything is ready to support this except a little bit of 
syntax in the .msh file to define the interpolation matrices. Until we 
have the time to complete this you still have to use the old parsed 
".pos" post-processing file format (since the INTERPOLATION_SCHEME is 
only available in the .pos file at the moment)... :-(


On 26/07/10 16:17, Gonçalo Pena wrote:
> Dear all,
> first of all, let me congratulate the developers for this piece of
> software. I started using it in the beginning of my PhD and nowadays,
> I'm trying to use it to visualize high order FE, and this is the reason
> behind this email.
>
> Some colleagues of mine and myself have been working recently on
> exporting high order finite elements from the code Life
> (https://life.prudhomm.org/) to visualize them in Gmsh. So far, with the
> help of the documentation, we managed to export (and visualize)
> successfully, polynomials defined in 2D geometries as long as the order
> of the geometrical element is the same as the degree of the polynomial
> to visualize. We're now working on different orders, for mesh and
> polynomials, say, visualizing P2 polynomials defined in a first order mesh.
>
> In the documentation, the answer seems to be in INTERPOLATION_SCHEME.
> However, it isn't very clear to me how to use this. Or, is it the case,
> that we need to have a PN mesh to visualize a PN polynomial, because we
> need the same number of nodes in $Nodes as in $ElementNodeData?
>
> I send also a test file that I produce with Life that has a scalar field
> to visualize. As you can notice, the fields are described in terms of
> second order polynomials, while the mesh is only first order.
>
>
> I appreciate any help regarding this.
> Best regards,
> Gonçalo Pena
>
>
>
>
>
>
>
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-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine