COMMENT ⊗   VALID 00002 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	(DECLARE (MAPEX T))
C00005 ENDMK
C⊗;
(DECLARE (MAPEX T))

(DEFUN DER1 (A) (LIST 'QUOTIENT (DERIV A) A))

(DEFUN (PLUS DERIV DERIV) (A)
       (CONS 'PLUS (MAPCAR 'DERIV A)))

(DEFUN (DIFFERENCE DERIV DERIV) (A)
       (CONS 'DIFFERENCE (MAPCAR 'DERIV 
				 A)))

(DEFUN (TIMES DERIV DERIV) (A)
	(LIST 'TIMES (CONS 'TIMES A)
		(CONS 'PLUS (MAPCAR 'DER1 A))))

(DEFUN (QUOTIENT DERIV DERIV) (A)
       (LIST 'DIFFERENCE 
	     (LIST 'QUOTIENT 
		   (DERIV (CAR A)) 
		   (CADR A))
	     (LIST 'QUOTIENT 
		   (CAR A) 
		   (LIST 'TIMES
			 (CADR A)
			 (CADR A)
			 (DERIV (CADR A))))))

 (DEFUN DERIV (A)
	(COND 
	 ((ATOM A)
	  (COND ((EQ A 'X) 1) (T 0)))
	 (T (LET ((DERIV (GET (CAR A) 'DERIV)))
		 (COND (DERIV (SUBRCALL T DERIV (CDR A)))
		       (T 'ERROR))))))

(DEFUN RUN ()
 (DECLARE (FIXNUM I))
 (DO ((I 0 (1+ I)))
     ((= I 1000.))
     (DERIV '(PLUS (TIMES 3 X X) (TIMES A X X) (TIMES B X) 5))
     (DERIV '(PLUS (TIMES 3 X X) (TIMES A X X) (TIMES B X) 5))
     (DERIV '(PLUS (TIMES 3 X X) (TIMES A X X) (TIMES B X) 5))
     (DERIV '(PLUS (TIMES 3 X X) (TIMES A X X) (TIMES B X) 5))
     (DERIV '(PLUS (TIMES 3 X X) (TIMES A X X) (TIMES B X) 5))))

(include "timer.lsp")

(timer timit 
	(run))