sides_rb Subroutine

  subroutine sides_rb(box, nc, iv, nb, gc)
    type(mg_box_t), intent(inout) :: box
    integer, intent(in)       :: nc
    integer, intent(in)       :: iv
    integer, intent(in)       :: nb
    !< Ghost cell direction
    !> Interpolated coarse grid ghost cell data (but not yet in the nb direction)
    real(dp), intent(in)      :: gc(nc, nc)
    integer                   :: di, dj, dk
    integer                   :: i, j, k, ix, dix

    if (mg_neighb_low(nb)) then
       ix = 1
       dix = 1
    else
       ix = nc
       dix = -1
    end if

    select case (mg_neighb_dim(nb))
    case (1)
       i = ix
       di = dix
       do k = 1, nc
          dk = -1 + 2 * iand(k, 1)
          do j = 1, nc
             dj = -1 + 2 * iand(j, 1)
             box%cc(i-di, j, k, iv) = 0.5_dp * gc(j, k) + 0.75_dp * box%cc(i,&
                 j, k, iv) - 0.25_dp * box%cc(i+di, j, k, iv)
          end do
       end do
    case (2)
       j = ix
       dj = dix
       do k = 1, nc
          dk = -1 + 2 * iand(k, 1)
          do i = 1, nc
             di = -1 + 2 * iand(i, 1)
             box%cc(i, j-dj, k, iv) = 0.5_dp * gc(i, k) + 0.75_dp * box%cc(i,&
                 j, k, iv) - 0.25_dp * box%cc(i, j+dj, k, iv)
          end do
       end do
    case (3)
       k = ix
       dk = dix
       do j = 1, nc
          dj = -1 + 2 * iand(j, 1)
          do i = 1, nc
             di = -1 + 2 * iand(i, 1)
             box%cc(i, j, k-dk, iv) = 0.5_dp * gc(i, j) + 0.75_dp * box%cc(i,&
                 j, k, iv) - 0.25_dp * box%cc(i, j, k+dk, iv)
          end do
       end do
    end select

  end subroutine sides_rb