Just another update

Task/Arithmetic-Complex/Clojure/arithmetic-complex.clj

@@ -0,0 +1,37 @@
+(ns rosettacode.arithmetic.cmplx
+  (:require [clojure.algo.generic.arithmetic :as ga])
+  (:import [java.lang Number]))
+
+(defrecord Complex [^Number r ^Number i]
+  Object
+  (toString [{:keys [r i]}]
+    (apply str
+      (cond
+        (zero? r) [(if (= i 1) "" i) "i"]
+        (zero? i) [r]
+        :else     [r (if (neg? i) "-" "+") i "i"]))))
+
+(defmethod ga/+ [Complex Complex]
+  [x y] (map->Complex (merge-with + x y)))
+
+(defmethod ga/+ [Complex Number] ; reals become y + 0i
+  [{:keys [r i]} y] (->Complex (+ r y) i))
+
+(defmethod ga/- Complex
+  [x] (->> x vals (map -) (apply ->Complex)))
+
+(defmethod ga/* [Complex Complex]
+  [x y] (map->Complex (merge-with * x y)))
+
+(defmethod ga/* [Complex Number]
+  [{:keys [r i]} y] (->Complex (* r y) (* i y)))
+
+(ga/defmethod* ga / Complex
+  [x] (->> x vals (map /) (apply ->Complex)))
+
+(defn conj [^Complex {:keys [r i]}]
+  (->Complex r (- i)))
+
+(defn inv [^Complex {:keys [r i]}]
+  (let [m (+ (* r r) (* i i))]
+    (->Complex (/ r m) (- (/ i m)))))