mpi_test.py doesn't run, fenics_mpi_example runs with mpirun -n 4 python3 fenics_mpi_example.py
and scales well with number of cores. mpi_test.py gives error point outside domain when run in
parallel, but works well single core.

Outside is not so important, as long as >100 points. Inside close to r=0 also not sensitive, but getting closer (> 75% * R) to boundary needs better mesh. Presumably due to high initial gradient.