Using Coarrays to Parallelize Legacy Fortran Applications: Strategy and Case Study

Listing 3

Parallel loop by splitting particles.

! Loop over the particles

do l = my_first_particle, my_last_particle, 4

  k = nint(sqrt(real(l) * 0.5))

  m = (l − (1 + 2 * k * (k − 1) − 4))/4

    ! First octant

    ! Do some computations

    ! Second octant

    ! Do some computations

    ! Third octant

    ! Do some computations

    ! Fourth octant

    ! Do some computations

end do