1 files changed, 0 insertions, 25 deletions
diff --git a/src/approx,derivative.lisp b/src/approx,derivative.lisp
deleted file mode 100644
index 631a5c0..0000000
--- a/src/approx,derivative.lisp
+++ /dev/null
@@ -1,25 +0,0 @@
-(in-package :lizfcm.approx)
-
-(defun central-derivative-at (f x &optional (delta 0.01))
-  (let* ((x2 (+ x delta))
-         (x1 (- x delta))
-         (y2 (apply f (list x2)))
-         (y1 (apply f (list x1))))
-    (/ (- y2 y1)
-       (- x2 x1))))
-
-(defun forward-derivative-at (f x &optional (delta 0.01))
-  (let* ((x2 (+ x delta))
-         (x1 x)
-         (y2 (apply f (list x2)))
-         (y1 (apply f (list x1))))
-    (/ (- y2 y1)
-       (- x2 x1))))
-
-(defun backward-derivative-at (f x &optional (delta 0.01))
-  (let* ((x2 x)
-         (x1 (- x delta))
-         (y2 (apply f (list x2)))
-         (y1 (apply f (list x1))))
-    (/ (- y2 y1)
-       (- x2 x1))))