festung/festung

The main project for the MATLAB / GNU Octave code of FESTUNG

FESTUNG

FESTUNG (Finite Element Simulation Toolbox for Unstructured Grids) is a Matlab / GNU Octave toolbox for the discontinuous Galerkin (DG) method on unstructured grids. It is primarily intended as a fast and flexible prototyping platform and testbed for students and developers.

FESTUNG relies on fully vectorized matrix/vector operations to deliver optimized computational performance combined with a compact, user-friendly interface and a comprehensive documentation.

Have a look at our gallery for example applications that use FESTUNG.

Get it

• The latest published version can always be downloaded from the GitHub repository. To check out the latest version, run

git clone https://github.com/FESTUNG/FESTUNG.git

• Tarballs of previous code versions and further information about the project can be found on our Project page.

Use it

Model problems are defined following a generic solver structure. Have a look at the implementation of the standard (element-based) DG discretizations of linear advection (folders advection for time-explicit and advection_implicit for time-implicit) or the LDG discretization of the diffusion operator (folder diffusion). A hybridized DG discretization of linear advection can be found in the folder hdg_advection.

Start the computation for any of these problems using main(<folder name>), for example

main('advection')

To change simulation parameters or modify initial and boundary data, have a look into configureProblem.m in the respective problem folder, or pass them directly when calling the problem solver, e.g.,

main('advection', 'tEnd', 10, 'p', 1, 'hmax', 2^-4)

to run the Advection problem with a different end time and linear ansatz functions on a mesh with maximum element size of 1/16.

Output files are written in VTK format or TecPlot ASCII file format and can be visualized, e.g., using Paraview.

Development

When developing code for or with FESTUNG we suggest to stick to the Naming convention to allow for better readability and a similar appearance of all code parts. Keep in mind the generic solver structure when modifying and adding new problems. All files should be documented using the Doxygen syntax.

For more details, see Using and contributing to FESTUNG.

Documentation

All routines are carefully documented in the Doxygen format, which allows to produce this documentation. It can be generated by calling doxygen in the main directory.

Contributors

The main developers of FESTUNG are Florian Frank, Balthasar Reuter, and Vadym Aizinger. Its initial release was developed at the Chair for Applied Mathematics I at Friedrich-Alexander University Erlangen-Nürnberg.

Since then, significant contributions were made by Hennes Hajduk and Andreas Rupp

Third party libraries

• FESTUNG makes extensive use of the built-in routines in MATLAB / GNU Octave.
• triquad was written by Greg von Winckel. See triquad.txt for license details.
• m2cpp.pl by Fabrice to generate a Doxygen documentation. See license.txt for license details.

License

FESTUNG is published under GPLv3, see License file.

Version

• Version 1.0 with an accompanying overview paper in preparation.
• Version 0.4 as published in the preprint Reuter, Rupp, Aizinger, Frank, Knabner: "FESTUNG: A MATLAB / GNU Octave toolbox for the discontinuous Galerkin method. Part IV: Generic problem framework and model-coupling interface". In: Communications in Computational Physics 28 (2020) 827-876, Available online June 2020, ISSN 1991-7120, https://doi.org/10.4208/cicp.OA-2019-0132 .
• Version 0.3 as published in the paper Jaust, Reuter, Aizinger, Schuetz, Knabner: "FESTUNG: A MATLAB / GNU Octave toolbox for the discontinuous Galerkin method. Part III: Hybridized discontinuous Galerkin (HDG) formulation". In: Computers & Mathematics with Applications 75.12 (2018) 4505-4533, Available online 2 May 2018, ISSN 0898-1221, https://doi.org/10.1016/j.camwa.2018.03.045 .
• Version 0.2 as published in the paper Reuter, Aizinger, Wieland, Frank, Knabner: "FESTUNG: A MATLAB / GNU Octave toolbox for the discontinuous Galerkin method. Part II: Advection operator and slope limiting". In: Computers & Mathematics with Applications 72 (2016) 1896-1925, Available online 25 August 2016, ISSN 0898-1221, https://doi.org/10.1016/j.camwa.2016.08.006 .
• Version 0.1 as published in the paper Frank, Reuter, Aizinger, Knabner: "FESTUNG: A MATLAB / GNU Octave toolbox for the discontinuous Galerkin method. Part I: Diffusion operator". In: Computers & Mathematics with Applications 70 (2015) 11-46, Available online 15 May 2015, ISSN 0898-1221, https://doi.org/10.1016/j.camwa.2015.04.013 .

Contact

Homepage: https://math.fau.de/FESTUNG

festung's Issues

the code for weak galerkin

I'm so sorry that it took a long time to do other things, I have written a code for a poisson equation using the weak galerkin method, it is also using the face basis which is similar to HDG, but there are some thing wrong when using the RT basis, i will rewrite it using [Pk, Pk].
I wondering is there a adaptive mesh, when FESTUNG runing?

Can we apply FESTUNG to hdg?

Dear reuterbal,
Thank you for answering my question several days ago.
Recently, I had read your first paper, and I was wondering if it would be possible for we to apply FESTUNG to hdg method as mentioned in the paper "An implicit high-order hybridizable discontinuous Galerkin method for linear convection–diffusion equations" ?
It seems just defining some more dg basis functions on the edges.

1D space

is it possible to use FESTUNG for 1D (in space) problems, like e.g. age dependent models?

The description of V2T, V2E, E0E?

Dear all,
I read the generateGridData.m but the description of V2T, V2E, E0E missing?

Requesting advice

Hi, I need to solve this equation for an implementation I'm working on. u is scalar and unknown while q is known and s is a test function.

Can you give some advice on how to do this?