semantic-net.lisp

这是人工智能老师上课讲的课件 中文

;;; These functions define a depth first inheritance search of a 
;;; semantic network.

(defun inherit-get (object property)
   (or (get object property)
       (get-from-parents (get object 'isa) property)))

(defun get-from-parents (parents property)
   (cond ((null parents) nil)
	 ((atom parents) (inherit-get parents property))
	 (t (or (get-from-parents (car parents) property)
	        (get-from-parents (cdr parents) property)))))

;;; These functions define a simple semantic network about animals.

(setf (get 'animal 'covering) 'skin)
(setf (get 'bird 'covering) 'feathers)
(setf (get 'bird 'travel) 'flies)
(setf (get 'bird 'isa) 'animal)
(setf (get 'fish 'isa) 'animal)
(setf (get 'fish 'travel) 'swim)
(setf (get 'ostrich 'isa) 'bird)
(setf (get 'ostrich 'travel) 'walk)
(setf (get 'penguin 'isa) 'bird)
(setf (get 'penguin 'travel) 'walk)
(setf (get 'penguin 'color) 'brown)
(setf (get 'opus 'isa) 'penguin)
(setf (get 'canary 'isa) 'bird)
(setf (get 'canary 'color) 'yellow)
(setf (get 'canary 'sound) 'sing)
(setf (get 'tweety 'isa) 'canary)
(setf (get 'tweety 'color) 'white)
(setf (get 'robin 'isa) 'bird)
(setf (get 'robin 'sound) 'sings)
(setf (get 'robin 'color) 'red)

;;;(inherit-get 'robin 'covering)