anchor.diff:    (let* ((ode-vars  (numerica-model-ode-vars nm))
            (allvars (query var))
            (klen-pos  nil))
  -    
  +    (format t "~&; Writing model block")
       (format file "MODEL ~A~%~
                     ~2TPARAMETER~%~
                       ~4Tk as ARRAY("
  
positive.code:                   ~2TVARIABLE~%~
                      ~4Tc as ARRAY(~S) of Concentration~%~
                    ~2TEQUATION"
              (make-string (length allvars) :initial-element #\space)
              (length ode-vars))
  
      ;; write the rate fns:
  
negative.code: 
  (defun write-simulation-block (nm file)
    (let ((vars (numerica-model-ode-vars nm)))
      (format t "~&;  Writing simulation block")
      (format file "SIMULATION ~A~%~
                    ~2TOPTIONS~%~
                      ~4TDYNAMIC_REPORTING_INTERVAL := 1 ;~%~
  