anchor.diff:    real(WP) :: total_time
     real(WP) :: twrite
   
  +
     init_start = omp_get_wtime()
     time = 0.0_WP
     dt = 0.0_WP
  
positive.code:     l = nc(i)
      do j = 1, l
        nb = nbs(i,j)
  
        dx = px(i) - px(nb)
        dy = py(i) - py(nb)
        dz = pz(i) - pz(nb)
  
negative.code:   ps_t = 0.0_WP
    tot_t = 0.0_WP
  
    call mass_change
  
    return
  end subroutine init
  
  