anchor.diff:    integer :: i, j, l, nb
     real(WP) :: sx, sy, sz
     real(WP) :: dx, dy, dz
  -  real(WP) :: k, scorr, surfk
  -  real(WP) :: c, Csurf, r2, m, q
  -
  -
  -  c = 45.0_WP*mass/PI/h5*BULK_MODULUS*0.5_WP
  +  real(WP) :: dvx, dvy, dvz
  +  real(WP) :: kpres, kvisc
  +  real(WP) :: cpres, cvisc, r2, m, q
  +
  +
  +  fx = 0.0_WP
  +  fy = 0.0_WP
  +  fz = 0.0_WP
  +
  +  cpres = 45.0_WP*mass/PI/h5*BULK_MODULUS*0.5_WP
  +  cvisc = -45.0_WP*mass/PI/h5*VISCOSITY
   
     do i = 1, n
       sx = 0.0_WP
  
positive.code:   use precision
    implicit none
  
    real(WP) :: neigh_t, dens_t, pres_t, visc_t, ef_t, ps_t, tot_t
  
  end module timers
  
  
negative.code: 
    neigh_t = neigh_t  + t2-t1
    dens_t  = dens_t   + t3-t2
    force_t = force_t  + t5-t3
    ef_t    = ef_t     + t6-t5
    ps_t    = ps_t     + t7-t6
  
  