amalloy

(defn unfold
  "Next and done? are functions that operate on a seed. next should
  return a pair, [value new-seed]; the value half of the pair is
  inserted into the resulting list, while the new-seed is used to
  continue unfolding. Notably, the value is never passed as an
  argument to either next or done?."
  [next done? seed]
  ((fn unfold*
     [seed]
     (lazy-seq

amalloy

(defn take-randnth [num coll]
  (take num
        (rest
         (map first
              (iterate (fn [[ret items]]
                         (let [idx (rand-int (count items))]
                           [(items idx)
                            (subvec (assoc items idx (items 0))
                                    1)]))
                       [nil

gist:621663

(ns mandel
  (:require [clojure.contrib.math :as math])
  (:gen-class))
 
(defn complex [r i]      
  [(double r) (double i)])

(defn add [[r1 i1] [r2 i2]]
  [(+ r1 r2) (+ i1 i2)])