From 02776c1e6ac9832755e9f972c9b9eb467f26f1b6 Mon Sep 17 00:00:00 2001
From: wirawan <wirawan>
Date: Thu, 7 Oct 2010 15:56:55 +0000
Subject: [PATCH] * Moving pyqmc.stats.avg to wpylib.math.stats.avg .

---
 math/stats/avg.py | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 math/stats/avg.py

diff --git a/math/stats/avg.py b/math/stats/avg.py
new file mode 100644
index 0000000..2d36ffe
--- /dev/null
+++ b/math/stats/avg.py
@@ -0,0 +1,29 @@
+# $Id: avg.py,v 1.1 2010-10-07 15:56:55 wirawan Exp $
+# Create: 20090112
+
+import math
+
+class avg(object):
+  def __init__(self):
+    self.clear()
+  def clear(self):
+    self.N = 0
+    self.sum1 = 0.0
+    self.sum2 = 0.0
+  def add(self, value):
+    self.N += 1
+    self.sum1 += value
+    self.sum2 += value*value
+    return self
+  #__add__ = add  << HERETICAL!!!
+  def mean(self):
+    return self.sum1 / self.N
+  def stddev(self):
+    N = self.N
+    avg1 = self.sum1 / N
+    avg2 = self.sum2 / N
+    return math.sqrt(abs( (avg2 - avg1**2) * N / (N - 1) ))
+
+# Operator overloading:
+avg.__iadd__ = avg.add
+avg.__call__ = avg.mean