cont-frac.scm

(define (cont-frac n d k)
  (define (cont-help i result)
    (if (= i 0)
	 result
	(cont-help (- i 1) (/ (n i) (+ (d i) result)))))
  (cont-help k 0.0))

(cont-frac (lambda (i) 1.0) (lambda (i) 1.0) 100)
;; A so-called k-term finite continued fraction
;; gives the value of the gold ratio
(define (cont-fact n d k)
  (define (cont-re i)
    (if (> i k)
	0
	(/ (n i) (+ (d i) (cont-re (+ i 1))))))
  (cont-re 1))

Exercise 1.38 sicp