generic: modified arithmetic and added math-functions

1 files changed, 61 insertions, 0 deletions

diff --git a/src/clojure/contrib/generic/math_functions.clj b/src/clojure/contrib/generic/math_functions.clj
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+++ b/src/clojure/contrib/generic/math_functions.clj
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+;; Generic interfaces for mathematical functions
+
+;; by Konrad Hinsen
+;; last updated March 13, 2009
+
+;; Copyright (c) Konrad Hinsen, 2009. All rights reserved.  The use
+;; and distribution terms for this software are covered by the Eclipse
+;; Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+;; which can be found in the file epl-v10.html at the root of this
+;; distribution.  By using this software in any fashion, you are
+;; agreeing to be bound by the terms of this license.  You must not
+;; remove this notice, or any other, from this software.
+
+(ns clojure.contrib.generic.math-functions
+  "Generic math function interface
+
+   NOTE: This library is VERY experimental. It WILL change significantly
+   with future release.
+
+   This library defines generic versions of common mathematical functions
+   such as sqrt or sin as multimethods that can be defined for any type."
+  (:use [clojure.contrib.def :only (defmacro-)]))
+
+(defmacro- defmathfn-1
+  [name]
+  (let [java-symbol (symbol "java.lang.Math" (str name))]
+    `(do
+       (defmulti ~name type)
+       (defmethod ~name java.lang.Number
+	 [~'x]
+	 (~java-symbol ~'x)))))
+
+(defn- two-types [x y] [(type x) (type y)])
+
+(defmacro- defmathfn-2
+  [name]
+  (let [java-symbol (symbol "java.lang.Math" (str name))]
+    `(do
+       (defmulti ~name two-types)
+       (defmethod ~name [java.lang.Number java.lang.Number]
+	 [~'x ~'y]
+	 (~java-symbol ~'x ~'y)))))
+
+; List of math functions taken from
+; http://java.sun.com/j2se/1.4.2/docs/api/java/lang/Math.html
+(defmathfn-1 abs)
+(defmathfn-1 acos)
+(defmathfn-1 asin)
+(defmathfn-1 atan)
+(defmathfn-2 atan2)
+(defmathfn-1 ceil)
+(defmathfn-1 cos)
+(defmathfn-1 exp)
+(defmathfn-1 floor)
+(defmathfn-1 log)
+(defmathfn-2 pow)
+(defmathfn-1 rint)
+(defmathfn-1 round)
+(defmathfn-1 sin)
+(defmathfn-1 sqrt)
+(defmathfn-1 tan)