-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathex_1_45.scm
36 lines (29 loc) · 976 Bytes
/
ex_1_45.scm
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
(define (compose f g) (lambda (x) (f (g x))))
(define (repeated f n)
(define (iter-repeated i result)
(if (= i 1)
result
(iter-repeated (- i 1) (compose result f))))
(lambda (x) ((iter-repeated n f) x)))
(define (average a b) (/ (+ a b) 2))
(define (average-damp f)
(lambda (x) (average x (f x))))
(define tolerance 0.00001)
(define (fixed-point f first-guess)
(define (close-enough? v1 v2)
(< (abs (- v1 v2)) tolerance))
(define (try guess)
(let ((next (f guess)))
(newline)
(display guess)
(if (close-enough? guess next)
next
(try next))))
(try first-guess))
(define (fixed-point-of-transform g transform guess)
(fixed-point (transform g) guess))
(define (log2 x) (/ (log x) (log 2)))
(define (root n x)
(fixed-point-of-transform (lambda (y) (/ x (expt y (- n 1))))
(repeated average-damp (floor (log2 n)))
1.0))