anchor.diff:  
   (defmethod unitg ((g g))
     "Unitize"
  -  (/gs g (norme g)))
  +  (/ g (norme g)))
   
   (defun recipbv (j &rest bvs)
     "jth reciprocal basis vector"
  -  (*gs (*g2 (apply #'*o (remove-nth j bvs))
  +  (* (*g (apply #'*o (remove-nth j bvs))
   	    (apply #'*o bvs))
          (expt -1 (1- j))))
   
  
positive.code: 		 for mji = (aref m j i)
  		 do (unless (zerop mji)
  		      (ong alb alc al
  			(setq tmp (g2+ tmp (*o2 (makeg class alb alc) 
  						(makeg class (ash 1 j) mji)))))))
  	      (setq al tmp))))
      al))
  
  
negative.code: 
  (defmethod invv ((g g))
    "Inverse of a versor"
    (/ (revg g) (scalar (*g2 g (revg g)))))
  
  ;; Reflection/rotation
  
  