anchor.diff:  		0))
   	g))
   
  -;; Arithmetic (addition, subtractions, scalar multiplication)
  -
  -(defmethod gbc+ ((g g) (b integer) c)
  -  "Add scalar C to GA object's B coefficient"
  +;;; Arithmetic (addition, subtractions, scalar multiplication)
  +
  +;;; Addition
  +
  +(defmethod ga-coef+ ((g g) (b integer) c)
  +  "Add scalar C to GA object's coefficient corresponfing to basis blade bitmap B"
     (mapg #'(lambda (bi ci)
   	    (if (= bi b)
   		(+ ci c)
   		ci))
   	g))
   
  -(defmethod gs+ ((g g) s)
  -  "Add GA object and scalar"
  -  (gbc+ g 0 s))
  -
  -(defmethod g2+ ((g1 g) (g2 g))
  -  "Add two GA objects"
  -  (assert (typep g1 (type-of g2)))
  -  (mapcg #'(lambda (c1 c2)
  -	     (if (and (numberzerop c1) (numberzerop c2))
  -		 0
  -		 (+ c1 c2)))
  -	 g1
  -	 g2))
  -
   (defmeth2 + ((g g) (s t))
  -  (gbc+ g 0 s))
  +  (ga-coef+ g 0 s))
   
   (defmeth2 + ((s t) (g g))
  -  (gbc+ g 0 s))
  +  (ga-coef+ g 0 s))
   
   (defmeth2 + ((g1 g) (g2 g))
     (mapcg #'(lambda (c1 c2)
  
positive.code:   (+ (* (unitg b) (- (sin (/ a 2))))
       (cos (/ a 2))))
  
  ;; Test functions
  (defmethod zerogp ((g g))
    "Test if GA object is zero"
    (null (grade g)))
  
negative.code: 		 (+ c1 c2)))
  	 g1 g2))
  
  ;;; Subtraction
  
  (defmeth2 - ((g g) (s t))
    (+ g (- s)))
  