commit b0170945a60133e0468161e069b3d817502f9091
parent 39c264bbafc10ad9997c21ae36995ab179d8d2b9
Author: rsiddharth <s@ricketyspace.net>
Date: Mon, 25 Sep 2017 02:27:07 +0000
net: Update (net ricketyspace sicp one twentynine)
* net/ricketyspace/sicp/one/twentynine.scm (simpsons): Rename function
to `simpson`; Add comments.
Diffstat:
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/net/ricketyspace/sicp/one/twentynine.scm b/net/ricketyspace/sicp/one/twentynine.scm
@@ -3,7 +3,7 @@
;;;; <https://creativecommons.org/licenses/by-sa/4.0/>.
(define-module (net ricketyspace sicp one twentynine)
- #:export (simpsons))
+ #:export (simpson))
(define (sum term a next b)
(if (> a b)
@@ -11,7 +11,7 @@
(+ (term a)
(sum term (next a) next b))))
-(define (simpsons f a b n)
+(define (simpson f a b n)
(let* ((h (/ (- b a) (* 1.0 n)))
(y (lambda (k) (+ a (* k h))))
(ce (lambda (k) ;coefficient
@@ -23,3 +23,12 @@
(next (lambda (k) (1+ k))))
(* (/ h 3.0)
(sum term 0 next n))))
+
+;;; Guile REPL
+;;; scheme@(guile-user)> ,use (net ricketyspace sicp one twentynine)
+;;; scheme@(guile-user)> (define (cube x) (* x x x))
+;;; scheme@(guile-user)> (simpson cube 0 1 100)
+;;; $23 = 0.24999999999999992
+;;; scheme@(guile-user)> (simpson cube 0 1 1000)
+;;; $24 = 0.2500000000000003
+