def test_percentage_difference_50pc(self): """Percentage difference between values where one is 50% of the other""" value_1 = 2000 value_2 = 4000 diff_1 = calc_percentage_difference(value_2, value_1) diff_2 = calc_percentage_difference(value_1, value_2) self.assertEquals(diff_1, diff_2) self.assertAlmostEquals(0.666, diff_1, 2)
def test_percentage_difference(self): """Percentage difference between two values that are almost equal""" value_1 = 3999.9999 value_2 = 4000 diff_1 = calc_percentage_difference(value_2, value_1) diff_2 = calc_percentage_difference(value_1, value_2) self.assertEquals(diff_1, diff_2) self.assertAlmostEquals(0.00000, diff_1, 2)
def test_percentage_difference_99pc(self): """Percentage difference between a very small value and a relatively large value""" value_1 = 0.0000000001 value_2 = 2**32 diff_1 = calc_percentage_difference(value_2, value_1) diff_2 = calc_percentage_difference(value_1, value_2) self.assertEquals(diff_1, diff_2) self.assertAlmostEquals(1.999999, diff_1, 2)