Clojure Problem of the Day #9

gistfile1.clj

(ns clj.core)


(def nums
  (range 0 10))


(defn fair []
  (rand-nth nums))

(defn unfair []
  (let [f1 #(rand-int 4)
        f2 (fair)]
    (rand-nth [f1 f2])))


(def expected-occurrence
  (/ 1 (count nums)))

(defn over-tolerance? [actual-occurrence tolerance]
  (-> (- (double actual-occurrence) expected-occurrence)
      (Math/abs)
      (> tolerance)))

(defn all-within-tolerance? [tolerance averages]
  (not-any? #(over-tolerance? % tolerance) averages))

(defn fair-random? [f n tolerance]
  (let [output(repeatedly n f)
        freq-vals (map val (frequencies output))
        averages(map #(/ % n) freq-vals)]
    (all-within-tolerance? tolerance averages)))