1 12687dd9 2023-08-04 jrmu ;; The first three lines of this file were inserted by DrScheme. They record metadata
 2 12687dd9 2023-08-04 jrmu ;; about the language level of this file in a form that our tools can easily process.
 3 12687dd9 2023-08-04 jrmu #reader(lib "htdp-intermediate-reader.ss" "lang")((modname 19.1.4) (read-case-sensitive #t) (teachpacks ((lib "draw.ss" "teachpack" "htdp"))) (htdp-settings #(#t constructor repeating-decimal #f #t none #f ((lib "draw.ss" "teachpack" "htdp")))))
 4 12687dd9 2023-08-04 jrmu (define (squared>? x c)
 5 12687dd9 2023-08-04 jrmu    (> (* x x) c))
 6 12687dd9 2023-08-04 jrmu 
 7 12687dd9 2023-08-04 jrmu ;filter : predicate list-of-numbers
 8 12687dd9 2023-08-04 jrmu ;Filters out all numbers in a-lon where the predicate of the number evaluates to false.  Retains all numbers that evaluate to true.
 9 12687dd9 2023-08-04 jrmu (define (filter predicate a-lon)
10 12687dd9 2023-08-04 jrmu   (cond
11 12687dd9 2023-08-04 jrmu     [(empty? a-lon) empty]
12 12687dd9 2023-08-04 jrmu     [(predicate (first a-lon)) (cons (first a-lon) (filter predicate (rest a-lon)))]
13 12687dd9 2023-08-04 jrmu     [else (filter predicate (rest a-lon))]))
14 12687dd9 2023-08-04 jrmu 
15 12687dd9 2023-08-04 jrmu (filter squared>? '(5 6 7 1 3 5 0 9 3 4 2))