Quick and dirty bargraph from Clojure frequencies

bargraph.clj

(defn bargraph
  "Quick'n'dirty bargraph from these `freqs`, the output from the function
   `clojure.core/frequencies`."
  [freqs]
  (let [u (/ (apply max (vals freqs)) 20)
        p (/ (apply +' (vals freqs)) 100)]
    (join "\n"
          (map #(format "%7d : %s (%d %%)" 
                        % 
                        (apply str (take (/ (freqs %) u) (repeat "#"))) 
                        (int (/ (freqs %) p)))
               (keys freqs)))))

;; generates output like:
;;      1 : # (0 %)
;;      2 : # (0 %)
;;      3 : #### (4 %)
;;      4 : ############ (17 %)
;;      5 : #################### (28 %)
;;      6 : ################## (25 %)
;;      7 : ################# (23 %)