From 17f7f88fcc9cd481131c722fa8e55309b28f4d05 Mon Sep 17 00:00:00 2001
From: stagas <gstagas@gmail.com>
Date: Sun, 9 Nov 2014 12:26:23 +0200
Subject: [PATCH] initial

---
 index.js | 11 +++++++++++
 test.js  | 27 +++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 index.js
 create mode 100644 test.js

diff --git a/index.js b/index.js
new file mode 100644
index 0000000..ea910d4
--- /dev/null
+++ b/index.js
@@ -0,0 +1,11 @@
+
+/**
+ * @module prewarp
+ * @author stagas
+ * @org opendsp
+ * @license mit
+ */
+
+export default function prewarp(f){
+  return Math.tan(Math.PI * f / sampleRate);
+}
diff --git a/test.js b/test.js
new file mode 100644
index 0000000..f0ea285
--- /dev/null
+++ b/test.js
@@ -0,0 +1,27 @@
+
+/**
+ * test
+ */
+
+import debug from 'debug';
+import prewarp from './index';
+
+var out = 0;
+
+var w = prewarp(0);
+var a = w / (1 + w);
+out += a.toFixed(1)==='0.0';
+
+var w = prewarp(sampleRate/4);
+var a = w / (1 + w);
+out += a.toFixed(1)==='0.5';
+
+var w = prewarp(sampleRate/2);
+var a = w / (1 + w);
+out += a.toFixed(1)==='1.0';
+
+debug(3 === out && 'all tests pass');
+
+export function dsp(t){
+  return 0;
+}