anchor.diff:            (format file "~%~2TEQUATION~%")
             (loop for eqn in eqns
                   for e = 1 then (1+ e)
  -                do (format file "~%~4T$c(~A) = ~{part~A~^+~};"
  -                           e eqn)))
  +                do (format file "~%~4T$c(~A) = ~:[0~;~{part~A~^+~}~];"
  +                           e eqn eqn)))
   
       ;; now, we've determine the actual # kvars ...
       ;; go back and scribble at klen-pos
  
positive.code:                                         (abstol nil) 
                                          (reltol nil)
                                          (gauss-value :mean) ; may be mean or random
                                          (base-units (compute-default-base-units-from-vars vars)))
    (format t "~&; Creating Numerica model...~%")
    (let+ ((*print-pretty*          nil)
           ((name path)             (parse-model-name name))
           (nm                      (make-numerica-model name
                                                         :path path
                                                         :ode-vars vars
                                                         :ode-comments-p ode-comments
                                                         :reltol reltol
                                                         :abstol abstol
                                                         :gauss-value gauss-value
                                                         :display-vars (order-vars (if (eq t display-vars) vars
                                                                                     display-vars))
                                                         :base-units  base-units))
           (pathname                (numerica-file-path (numerica-model-name nm) path)))
  
          (when (ok-to-overwrite overwrite pathname)
            (unless vars
              (warn "*** No ode vars selected ***~%"))
            (format t "~&; Computing Numerica code...~%")
            (with-open-file (stream pathname :direction :output :if-does-not-exist :create :if-exists :supersede)
              (let ((*math-print-function*   (compute-numerica-math-print-function nm)))
                (write-numerica-code nm stream))))
          (setf *numerica-model* nm)))
  
  
  ;;;; (defun refresh-parameters (&optional (model *model*))
  
negative.code:   :authors ("Aneil Mallavarapu"))
  
  (define-var *numerica-model* ())
  (define-var *numerica-rate-string-max-length* 2000
    "Part of a horrendous kludge to deal with a numerica bug")
  
  (define-function create-numerica-model (name &key 
  