Line data    Source code

       1             : module m_divide_most_evenly 
       2             :    use m_judft
       3             : contains
       4         148 :    subroutine divide_most_evenly(n_total, n_parts, start_idx, psize)
       5             :       implicit none
       6             :       integer, intent(in)                 :: n_total, n_parts
       7             :       integer, allocatable, intent(inout) :: start_idx(:), psize(:)
       8             : 
       9             :       integer             :: i, big_size, small_size, end_idx
      10             : 
      11         148 :       if(allocated(start_idx)) deallocate(start_idx)
      12         148 :       if(allocated(psize)) deallocate(psize)
      13         592 :       allocate(start_idx(n_parts), psize(n_parts))
      14             : 
      15         148 :       if(n_parts == 0) call judft_error("You need more than 0 parts")
      16         148 :       if(n_parts > n_total) call judft_error("You can't have more n_parts, than n_total")
      17             : 
      18         148 :       small_size = floor((1.0*n_total)/n_parts)
      19         148 :       big_size = small_size +1
      20             : 
      21         148 :       end_idx = 0
      22         296 :       do i = 1,n_parts
      23         148 :          psize(i) = merge(big_size, small_size,i <= mod(n_total, n_parts))
      24         148 :          if(psize(i) == 0) then
      25           0 :             write (*,*) "n_total, n_parts", n_total, n_parts
      26           0 :             call judft_warn("some band_packs have 0 bands")
      27             :          endif
      28         148 :          start_idx(i) = end_idx + 1
      29         296 :          end_idx = start_idx(i) + psize(i) - 1
      30             :       enddo
      31         148 :    end subroutine divide_most_evenly
      32             : end module m_divide_most_evenly