anchor.diff:      ! un-normalized weight for alpha in the integrals; prop. to p(alpha|x)
       real(real64), intent(in) :: alpha
   
  -    log_weight = log(alpha_prior(alpha)) + log_pna(alpha)
  +    log_weight = log(alpha_prior(alpha)) + log_pna_u(alpha)
   
     end function log_weight
   
  
positive.code: 
    end function log_pna
  
    elemental real(real64) function alpha_prior(alpha)
      ! prop. to p(alpha) - the prior for alpha in NSB estimator
      use constants
  
negative.code: 
    elemental real(real64) function log_weight(alpha)
      ! un-normalized weight for alpha in the integrals; prop. to p(alpha|x)
      use dirichlet_mod, only: log_pna_u, alpha_prior
  
      real(real64), intent(in) :: alpha
  
      log_weight = log(alpha_prior(alpha)) + log_pna_u(alpha)
  
    end function log_weight
  
  