Added a couple of macros

derive.lisp

@@ -6,7 +6,9 @@
   (:use #:cl)
   (:export :derive
            :csc
-           :sec))
+           :sec
+           :define-equation-functions
+           :take-derivative))
 
 (in-package #:derive)
 
@@ -110,4 +112,18 @@ Calculate the cosecant of x"
 Calculate the secant of x"
   (/ (cos x)))
 
+(defmacro define-equation-functions (name variable equation)
+  (let ((derivative-name
+         (intern (string-upcase (format nil "d/d~a-~a" variable name))))
+        (derivative (derive equation)))
+    `(progn
+       (defun ,name (,variable)
+         ,equation)
+       (defun ,derivative-name (,variable)
+         ,derivative))))
+
+(defmacro take-derivative (equation)
+  (let ((derivative (derive equation)))
+    `',derivative))
+
 ;;; End derive