toolkit/javascript/d3/src/core/random.js
changeset 47 c0b4a8b5a012
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/src/core/random.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,15 @@
+d3.random = {
+  normal: function(mean, deviation) {
+    if (arguments.length < 2) deviation = 1;
+    if (arguments.length < 1) mean = 0;
+    return function() {
+      var x, y, r;
+      do {
+        x = Math.random() * 2 - 1;
+        y = Math.random() * 2 - 1;
+        r = x * x + y * y;
+      } while (!r || r > 1);
+      return mean + deviation * x * Math.sqrt(-2 * Math.log(r) / r);
+    };
+  }
+};