Submitting an MPI (parallel) job

If you already have a properly built and tested executable, submitting the job is a piece of cake.
For example, to submit a parallel Qs job, proceed as follows:

#!/bin/tcsh -f
 
mpirun -np 4 Qs_MPI example.in > LOG
 
exit
sbatch -p fast -N1 -n4 Qs.csh
sbatch -N1 -n4 Qs.csh