test/test_online.py

   1 #!/usr/bin/env python
   2 """Module Description: Test functions for online algorithm functions.
   3
   4 This code is free software; you can redistribute it and/or modify it
   5 under the terms of the BSD License (see the file LICENSE included with
   6 the distribution).
   7 """
   8
   9 import unittest
  10 import numpy as np
  11 from math import sqrt
  12 # ------------------------------------
  13 # Main function
  14 # ------------------------------------
  15
  16 def update_m_s(x, c, m, s):
  17     c += 1
  18     delta = x - m
  19     m += delta / c
  20     s += delta * (x - m)
  21     return(c, m, s)
  22
  23 class Test_Mean(unittest.TestCase):
  24     def setUp( self ):
  25         # np.random.randint(1,1000,size=10)
  26         self.data = [410, 710, 891, 312, 453, 460, 237, 622, 268]
  27         # [np.mean(self.data[0:x]) for x in range(0,len(self.data)+1)]
  28         self.correct_mean = [410.0, 560.0, 670.3333333333334, 580.75, 555.2, 539.3333333333334, 496.14285714285717, 511.875, 484.77777777777777]
  29         # [np.std(self.data[0:x]) for x in range(0,len(self.data)+1)]
  30         self.correct_stddev = [0.0, 150.0, 198.36050234078579, 231.48582569997671, 213.25984150795946, 197.8852080261573, 211.55845431425504, 202.2247743848414, 205.48737608036913]
  31
  32     def test_mean( self ):
  33         c = 1
  34         m = self.data[ 0 ]
  35         s = 0
  36         for i in range( 1, len( self.data ) ):
  37             (c, m, s) = update_m_s( self.data[ i ], c, m, s )
  38             mean = m
  39             std = sqrt( s/c )
  40             self.assertAlmostEqual( self.correct_mean[i], m, 2 )
  41             self.assertAlmostEqual( self.correct_stddev[i], std,  2 )
  42
  43