80 lines
2.9 KiB
Scheme
80 lines
2.9 KiB
Scheme
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;;; File: dderiv.sc
|
|
;;; Description: DDERIV benchmark from the Gabriel tests
|
|
;;; Author: Vaughan Pratt
|
|
;;; Created: 8-Apr-85
|
|
;;; Modified: 10-Apr-85 14:53:29 (Bob Shaw)
|
|
;;; 23-Jul-87 (Will Clinger)
|
|
;;; 9-Feb-88 (Will Clinger)
|
|
;;; 21-Mar-94 (Qobi)
|
|
;;; 31-Mar-98 (Qobi)
|
|
;;; 26-Mar-00 (flw)
|
|
;;; Language: Scheme (but see note below)
|
|
;;; Status: Public Domain
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
;;; Note: This benchmark uses property lists. The procedures that must
|
|
;;; be supplied are get and put, where (put x y z) is equivalent to Common
|
|
;;; Lisp's (setf (get x y) z).
|
|
|
|
;;; DDERIV -- Symbolic derivative benchmark written by Vaughan Pratt.
|
|
|
|
;;; This benchmark is a variant of the simple symbolic derivative program
|
|
;;; (DERIV). The main change is that it is `table-driven.' Instead of using a
|
|
;;; large COND that branches on the CAR of the expression, this program finds
|
|
;;; the code that will take the derivative on the property list of the atom in
|
|
;;; the CAR position. So, when the expression is (+ . <rest>), the code
|
|
;;; stored under the atom '+ with indicator DERIV will take <rest> and
|
|
;;; return the derivative for '+. The way that MacLisp does this is with the
|
|
;;; special form: (DEFUN (FOO BAR) ...). This is exactly like DEFUN with an
|
|
;;; atomic name in that it expects an argument list and the compiler compiles
|
|
;;; code, but the name of the function with that code is stored on the
|
|
;;; property list of FOO under the indicator BAR, in this case. You may have
|
|
;;; to do something like:
|
|
|
|
;;; :property keyword is not Common Lisp.
|
|
|
|
|
|
(define (dderiv-aux a) (list '/ (dderiv a) a))
|
|
|
|
(define (+dderiv a) (cons '+ (map dderiv a)))
|
|
|
|
(put '+ 'dderiv +dderiv) ; install procedure on the property list
|
|
|
|
(define (-dderiv a) (cons '- (map dderiv a)))
|
|
|
|
(put '- 'dderiv -dderiv) ; install procedure on the property list
|
|
|
|
(define (*dderiv a) (list '* (cons '* a) (cons '+ (map dderiv-aux a))))
|
|
|
|
(put '* 'dderiv *dderiv) ; install procedure on the property list
|
|
|
|
(define (/dderiv a)
|
|
(list '-
|
|
(list '/ (dderiv (car a)) (cadr a))
|
|
(list '/
|
|
(car a)
|
|
(list '* (cadr a) (cadr a) (dderiv (cadr a))))))
|
|
|
|
(put '/ 'dderiv /dderiv) ; install procedure on the property list
|
|
|
|
(define (dderiv a)
|
|
(cond ((not (pair? a)) (cond ((eq? a 'x) 1) (else 0)))
|
|
(else (let ((dderiv (get (car a) 'dderiv)))
|
|
(cond (dderiv (dderiv (cdr a)))
|
|
(else 'error))))))
|
|
|
|
(define (run)
|
|
(do ((i 0 (+ i 1))) ((= i 1000))
|
|
(dderiv '(+ (* 3 x x) (* a x x) (* b x) 5))
|
|
(dderiv '(+ (* 3 x x) (* a x x) (* b x) 5))
|
|
(dderiv '(+ (* 3 x x) (* a x x) (* b x) 5))
|
|
(dderiv '(+ (* 3 x x) (* a x x) (* b x) 5))
|
|
(dderiv '(+ (* 3 x x) (* a x x) (* b x) 5))))
|
|
|
|
|
|
;(time (do ((i 10 (- i 1))) ((zero? i)) (run)))
|
|
(run)
|
|
(display (dderiv '(+ (* 3 x x) (* a x x) (* b x) 5)))
|
|
(newline)
|