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37 * Tests \Gromacs-specific test assertions.
39 * \author Teemu Murtola <teemu.murtola@gmail.com>
40 * \ingroup module_testutils
42 #include "testutils/testasserts.h"
44 #include <gtest/gtest.h>
49 using ::testing::internal::FloatingPoint;
52 * Helper to produce floating-point numbers with specified ULP difference.
54 * This doesn't work if the value would change sign.
56 * \ingroup module_testutils
58 template <typename FloatType>
59 FloatType addUlps(FloatType value, int ulps)
61 return FloatingPoint<FloatType>::ReinterpretBits(
62 FloatingPoint<FloatType>(value).bits() + ulps);
65 using ::gmx::test::FloatingPointDifference;
67 TEST(FloatingPointDifferenceTest, HandlesEqualValues)
69 FloatingPointDifference diff(1.2, 1.2);
70 EXPECT_FALSE(diff.isNaN());
71 EXPECT_EQ(0.0, diff.asAbsolute());
72 EXPECT_EQ(0U, diff.asUlps());
73 EXPECT_FALSE(diff.signsDiffer());
76 TEST(FloatingPointDifferenceTest, HandlesZerosOfDifferentSign)
78 FloatingPointDifference diff(0.0, GMX_DOUBLE_NEGZERO);
79 EXPECT_FALSE(diff.isNaN());
80 EXPECT_EQ(0.0, diff.asAbsolute());
81 EXPECT_EQ(0U, diff.asUlps());
82 EXPECT_TRUE(diff.signsDiffer());
85 TEST(FloatingPointDifferenceTest, HandlesSignComparisonWithZero)
88 FloatingPointDifference diff(0.0, -1.2);
89 EXPECT_FALSE(diff.isNaN());
90 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
91 EXPECT_TRUE(diff.signsDiffer());
94 FloatingPointDifference diff(GMX_DOUBLE_NEGZERO, -1.2);
95 EXPECT_FALSE(diff.isNaN());
96 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
97 EXPECT_FALSE(diff.signsDiffer());
101 TEST(FloatingPointDifferenceTest, HandlesUlpDifferences)
103 const double first = 1.0;
104 const double second = addUlps(first, 2);
106 FloatingPointDifference diff(first, second);
107 EXPECT_FALSE(diff.isNaN());
108 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
109 EXPECT_EQ(2U, diff.asUlps());
110 EXPECT_FALSE(diff.signsDiffer());
113 FloatingPointDifference diff(second, first);
114 EXPECT_FALSE(diff.isNaN());
115 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
116 EXPECT_EQ(2U, diff.asUlps());
117 EXPECT_FALSE(diff.signsDiffer());
121 TEST(FloatingPointDifferenceTest, HandlesUlpDifferenceAcrossZero)
123 const double first = addUlps(GMX_DOUBLE_NEGZERO, 2);
124 const double second = addUlps( 0.0, 2);
125 FloatingPointDifference diff(first, second);
126 EXPECT_FALSE(diff.isNaN());
127 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
128 EXPECT_EQ(4U, diff.asUlps());
129 EXPECT_TRUE(diff.signsDiffer());
132 TEST(FloatingPointDifferenceTest, HandlesNaN)
134 const double first = std::numeric_limits<double>::quiet_NaN();
135 const double second = 2.0;
136 FloatingPointDifference diff(first, second);
137 EXPECT_TRUE(diff.isNaN());