sc_make_subcom_1 Subroutine

  subroutine sc_make_subcom_1(self)
    use mp, only: comm_type, split, free_comm, mp_undefined, sum_allreduce_sub
    implicit none
    class(supercell_type), intent(inout) :: self
    integer :: ic, colour
    type(comm_type) :: tmp

    !/First make a subcommunicator involving any procs
    !which can see this supercell
    colour = 0
    if(self%is_local) colour = 1
    !Here we check if the new subcom has same number of members as
    !parent, if so we can carry on using the parent instead
    call sum_allreduce_sub(colour, self%parent_sub%id)

    if (colour == self%parent_sub%nproc) then
       self%sc_sub_all=self%parent_sub
    else
       colour = mp_undefined
       if(self%is_local) colour = 1

       call split(colour,tmp,self%parent_sub%id)
       !Note we only store the subcom for those procs which will use it
       !this ensures an error will occur if we try to use the subcom in
       !the wrong place
       if(self%is_local)then
          self%sc_sub_all=tmp
       else
          !If we can't see any of this object then
          !return
          return
       endif
    endif

    !Now make the supercell sub communicators
    do ic=1,self%ncell
       !Set parent subcom
       self%cells(ic)%parent_sub=self%sc_sub_all
    enddo

  end subroutine sc_make_subcom_1