Explore a Cartesian grid process topology by writing a toy program, where
- the MPI processes are arranged into a 2D Cartesian grid
- every task prints out their linear rank together with its coordinates in the process grid
- every task prints out the linear rank of their nearest neighboring processes
Run the code with both periodic and non-periodic boundaries, and experiment
with the direction and displacement parameters of the MPI_Cart_shift
routine.
You can start from scratch or use one of the provided skeleton codes (skeleton.c or skeleton.f90).