mutate.clj

(map (fn [x] (if (should-mutate?)
                 (mutate x)
                 x)
      population))

(defn mutate [genome]
  "swaps two sets of random elements in the given genome"
  (let [a (rand-int (count genome))
        b (rand-int (count genome))
        c (rand-int (count genome))
        d (rand-int (count genome))]
    (swap (swap genome c d) a b)))

(defn swap [v i1 i2]
  "swaps two elements in a vector"
  (assoc v i2 (v i1) i1 (v i2)))

(def mutation-chance 15)

(defn should-mutate? []
  "determines whether or not a given genome
   should be mutated"
  (< (rand-int 100) mutation-chance))