anchor.diff:  
     n_threads = omp_get_max_threads()
     allocate(state(n_threads))
  -
  +  seed = PTread_c_int64(config, 'seed')
     do i = 1, n_threads
        state(i)%counter%c0 = 0
        state(i)%counter%c1 = 0
        state(i)%key%c0 = 0
  -     state(i)%key%c1 = 1110987654321_c_long
  +     state(i)%key%c1 = seed
     end do
   
     call h5open_f(error)
  
positive.code:   type(h5md_element_t) :: elem_v_com
    integer(HID_T) :: box_group, solvent_group
  
    integer :: i, L(3), seed_size, clock, error, N, n_threads
    integer :: rho
    integer :: N_loop, N_therm
    integer, allocatable :: seed(:)
  
    double precision :: v_com(3), wall_v(3,2), wall_t(2)
    double precision :: gravity_field(3)
  
negative.code:   call e_solvent% append(solvent% pos, i, i*tau)
    call e_solvent_v% append(solvent% vel, i, i*tau)
  
    call e_solvent% close()
    call e_solvent_v% close()
    call elem_tz% close()
  