I am trying to run an example of poison equation with periodic boundaries from here https://fenicsproject.org/olddocs/dolfin/1.4.0/python/demo/documented/periodic/python/documentation.html
Apparenty, this one is for older version only, since it produces an error. Is there any example of periodic boundaries for the latest version of Fenics? Thank you!
Is there any reason that @dokken 's multipoint constraint code has not been rolled into the main fenicsx repository? I’ve seen his code mentioned before with regard to periodic boundary conditions. This suggests to me that mpc code is stable. In general what does it take to get a new feature adopted?
Because the code is quite intrusive.
The code does special operations during assembly to account for multi-point constraints, which is not needed for most FEM problems.
The MPC implementation is far more general than what is supported in the «old» dolfin code.
One of the core ideas of dolfinx is that the the core library should be fairly small, consisting of highly efficient and maintainable code, while extensions should live in stand alone packages.
For ideas to be merged into Dolfinx, one should propose the idea on the issue tracker, and will then get feedback on if the idea is suitable for the core library, or more suitable as an extension.