anchor.diff:      end do
   
     end subroutine compute_rho
  -  
  +
  +  !> Compute x-velocity profile along z
     subroutine compute_vx(particles, vx)
       type(particle_system_t), intent(in) :: particles
       type(profile_t), intent(inout) :: vx
  
positive.code: 
    end subroutine simple_mpcd_step
  
    !! Collisions in partially filled cells at the walls use the rule of
    !! Lamura, Gompper, Ihle and Kroll, EPL 56, 319-325 (2001)
    !! http://dx.doi.org/10.1209/epl/i2001-00522-9
    subroutine wall_mpcd_step(particles, cells, state, wall_temperature, wall_v, wall_n, &
  
negative.code: 
    end subroutine mpcd_stream_zwall
  
    !> Stream MPCD particles in a periodic system
    subroutine mpcd_stream_periodic(particles, cells, dt)
      type(particle_system_t), intent(inout) :: particles
      type(cell_system_t), intent(in) :: cells
  