Fast vector math in Clojure / Incanter

Question

I\'m currently looking into Clojure and Incanter as an alternative to R. (Not that I dislike R, but it just interesting to try out new languages.) I like Incanter and find the s

Answer 1

Here's a solution with transients - appealing but slow.

(use 'incanter.stats)
(set! *warn-on-reflection* true)
(def x (doall (sample-normal 1e7)))

(time
 (def y
      (loop [xs x
             xs+ (rest x)
             result (transient [])]
        (if (empty? xs+)
          (persistent! result)
          (recur (rest xs) (rest xs+)
                 (conj! result (- (double (first xs+))
                                  (double (first xs)))))))))