anchor.diff:      integer, intent(in) :: nplanets
       real(kind=8), intent(in), dimension(5*nplanets+1) :: planetpar
       real(kind=8), intent(in), dimension(4) :: hyperpar
  +    character(len=*), intent(in) :: meanf
   
       !! Gaussian process variables
       !type(WhiteKernel), target :: k2
  
positive.code: subroutine gp_predictor(times, rvs, errors, pred, planetpar, hyperpar, nplanets, nt)
      use gputils
      implicit none
  
  
negative.code:     kernel_to_pass => k8
  
      gp1 = GP(k8%evaluate_kernel(times, times), kernel_to_pass)
      if (meanf == 'constant') then
          print *, 'constant'
          gp1%mean_fun => mean_fun_constant
      else
          gp1%mean_fun => mean_fun_keplerian
      endif
  
      gp_n_planets = nplanets
      gp_n_planet_pars = 5*nplanets + 1
  