1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
# Copyright 2014 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import math
import unittest
import math_utils
class MathUtilsTest(unittest.TestCase):
"""Tests for mathematical utility functions."""
def testTruncatedMeanRaisesError(self):
"""TruncatedMean should raise an error when passed an empty list."""
with self.assertRaises(TypeError):
math_utils.TruncatedMean([], 0)
def testMeanSingleNum(self):
"""Tests the Mean function with a single number."""
self.assertEqual(3.0, math_utils.Mean([3]))
def testMeanShortList(self):
"""Tests the Mean function with a short list."""
self.assertEqual(0.5, math_utils.Mean([-3, 0, 1, 4]))
def testMeanCompareAlternateImplementation(self):
"""Tests Mean by comparing against an alternate implementation."""
def AlternateMeanFunction(values):
"""Simple arithmetic mean function."""
return sum(values) / float(len(values))
test_values_lists = [[1], [5, 6.5, 1.2, 3], [-3, 0, 1, 4],
[-3, -1, 0.12, 0.752, 3.33, 8, 16, 32, 439]]
for values in test_values_lists:
self.assertEqual(
AlternateMeanFunction(values),
math_utils.Mean(values))
def testRelativeChange(self):
"""Tests the common cases for calculating relative change."""
# The change is relative to the first value, regardless of which is bigger.
self.assertEqual(0.5, math_utils.RelativeChange(1.0, 1.5))
self.assertEqual(0.5, math_utils.RelativeChange(2.0, 1.0))
def testRelativeChangeFromZero(self):
"""Tests what happens when relative change from zero is calculated."""
# If the first number is zero, then the result is not a number.
self.assertEqual(0, math_utils.RelativeChange(0, 0))
self.assertTrue(
math.isnan(math_utils.RelativeChange(0, 1)))
self.assertTrue(
math.isnan(math_utils.RelativeChange(0, -1)))
def testRelativeChangeWithNegatives(self):
"""Tests that relative change given is always positive."""
self.assertEqual(3.0, math_utils.RelativeChange(-1, 2))
self.assertEqual(3.0, math_utils.RelativeChange(1, -2))
self.assertEqual(1.0, math_utils.RelativeChange(-1, -2))
if __name__ == '__main__':
unittest.main()
|
