Finite element software deal.II version 8.0 released

[Wolfgang Bangerth]

Version 8.0 of deal.II, the object-oriented finite element library awarded the
J. H. Wilkinson Prize for Numerical Software, has been released. It is
available for free under an Open Source license from the deal.II homepage at

http://www.dealii.org/

This is a major new release. In particular, it features the following changes:
- The configuration and build system has been switched to cmake, providing
better support for a wide variety of platforms including Microsoft Windows,
better integration with IDEs such as Eclipse, and many other advantages.
- deal.II now supports 64bit indices for problems with more than 2
billion unknowns and has been tested on problems of up to 27 billion
unknowns.
- deal.II is now licensed under the LGPL.

Further changes include:
- Improvements to parallel linear algebra
- Improvements to multithreading
- Hundreds of new features and bugfixes

The main features of deal.II are:
- Extensive documentation and 46 working example programs
- Support for dimension-independent programming
- Locally refined adaptive meshes
- Multigrid support
- A zoo of different finite elements
- Fast linear algebra
- Built-in support for shared memory and distributed parallel computing,
scaling from laptops to clusters with 10,000s of processor cores
- Interfaces to Trilinos, PETSc, METIS, UMFPACK and other external software
- Output for a wide variety of visualization platforms.

Wolfgang Bangerth, Timo Heister, Guido Kanschat, and many other contributors.

--
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Wolfgang Bangerth email: bang...@math.tamu.edu
www: http://www.math.tamu.edu/~bangerth/

[Wolfgang Bangerth]

All,
I'd like to point out one particular change of importance in the new version
8.0: The license under which deal.II is distributed has been changed from the
QPL to the LGPL (version 2.1 or later, at the user's discretion).

The QPL is a variant of the GPL that was used occasionally in the late 1990s
when deal.II started, but it has since fallen out of favor. Furthermore, we
have occasionally heard that people wanted to use deal.II in commercial
contexts, and the GPL makes this difficult. We had therefore decided 3 years
ago at a workshop in Heidelberg to switch to the LGPL -- a more liberal
license -- but it took a very long time to figure out how one would facilitate
a license switch and then to get every significant contributor's signature.

I would like to thank all of those who helped in this process. It is our hope
that this change allows deal.II to be used in contexts in which it was
previously impossible -- and that this extended use is good for our community
as well, through increased contributions from others, or through job
opportunities for those who know deal.II that wouldn't be available otherwise.

Best
Wolfgang (and I'm sure I'm also speaking for Guido, Timo and all others
involved in this!)

[Wolfgang Bangerth]

> Wolfgang Bangerth, Timo Heister, Guido Kanschat, and many other contributors.

In particular, I'd like to point out:

1/ Matthias Maier has done an incredible amount of work in converting the
existing autoconf-based configuration and build system to cmake. The new
system has more than 10,000 lines of cmake code, which gives you an idea of
how much work this was.

2/ Bruno Turcksin and Kainan Wang went through the entire code base to inspect
every single occurrence of "unsigned int" to see whether it corresponds to a
global DoF index, and if so replaced it by types::global_dof_index. (This
followed an initial, rough conversion we started with many volunteers at last
year's users workshop.) They then fixed dozens of bugs that were left and
verified that it all works on 1000s of processors. The final patch when this
work was merged had more than 60,000 lines.

3/ As always, many others have contributed pieces large and small. In
particular, the following people all did (I hope I didn't forget anyone):
Ashkan Dorostkar
Bruno Turcksin
Christian Wuelker
Denis Davydov
Fahad Alrashed
Felix Gruber
Guido Kanschat
Joerg Frohne
Juan Carlos Araujo Cabarcas
Kainan Wang
Martin Kronbichler
Martin Steigemann
Matthias Maier
Scott Miller
Spencer Patty
Timo Heister
Wolfgang Bangerth

All of these contributions are greatly appreciated!

Best
W.