distance.clj

(ns distance
  (:use [clojure.contrib.seq :only [indexed]]))

(defn- min-dist
  [index inums]
  (apply min (map #(Math/abs (- index %)) inums)))

(defn rel-distance
  [indexes elems]
  (let [ielems (indexed elems)
	idxs (if (vector? indexes) indexes (vector indexes))]
    (map #(min-dist (first %) idxs) ielems)))

;; (rel-distance 3 [:a :b :c :d :e])
;; -> (3 2 1 0 1)

;; (rel-distance [3 5] [:a :b :c :d :e :f :g :h])
;; -> (3 2 1 0 1 0 1 2)