ky_make_subcom_1 Subroutine

  subroutine ky_make_subcom_1(self)
    use mp, only: comm_type, split, free_comm, mp_undefined, sum_allreduce_sub
    implicit none
    class(ky_type), intent(inout) :: self
    integer :: is, colour
    type(comm_type) :: tmp
    !/First make a subcommunicator involving any procs
    !which can see this ky block
    colour = 0
    if(self%is_local) colour = 1
    call sum_allreduce_sub(colour, self%parent_sub%id)

    if ( colour == self%parent_sub%nproc) then
          self%ky_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%ky_sub_all=tmp
       else
          return
       endif
    endif

    !Now make the supercell sub communicators
    do is=1,self%nsupercell
       !Set parent subcom
       self%supercells(is)%parent_sub=self%ky_sub_all

       !Now make child subcom
       call self%supercells(is)%make_subcom_1
    enddo
  end subroutine ky_make_subcom_1