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37 * Tests \Gromacs-specific test assertions.
39 * \author Teemu Murtola <teemu.murtola@gmail.com>
40 * \ingroup module_testutils
44 #include "testutils/testasserts.h"
46 #include <gtest/gtest.h>
51 using ::testing::internal::FloatingPoint;
54 * Helper to produce floating-point numbers with specified ULP difference.
56 * This doesn't work if the value would change sign.
58 * \ingroup module_testutils
60 template<typename FloatType>
61 FloatType addUlps(FloatType value, int ulps)
63 return FloatingPoint<FloatType>::ReinterpretBits(FloatingPoint<FloatType>(value).bits() + ulps);
66 using ::gmx::test::FloatingPointDifference;
68 TEST(FloatingPointDifferenceTest, HandlesEqualValues)
70 FloatingPointDifference diff(1.2, 1.2);
71 EXPECT_TRUE(diff.isDouble());
72 EXPECT_FALSE(diff.isNaN());
73 EXPECT_EQ(0.0, diff.asAbsolute());
74 EXPECT_EQ(0U, diff.asUlps());
75 EXPECT_FALSE(diff.signsDiffer());
78 // TODO: Use typed tests to run all the tests for single and double.
79 TEST(FloatingPointDifferenceTest, HandlesFloatValues)
81 FloatingPointDifference diff(1.2F, 1.2F);
82 EXPECT_FALSE(diff.isDouble());
83 EXPECT_FALSE(diff.isNaN());
84 EXPECT_EQ(0.0, diff.asAbsolute());
85 EXPECT_EQ(0U, diff.asUlps());
86 EXPECT_FALSE(diff.signsDiffer());
89 TEST(FloatingPointDifferenceTest, HandlesZerosOfDifferentSign)
91 FloatingPointDifference diff(0.0, GMX_DOUBLE_NEGZERO);
92 EXPECT_FALSE(diff.isNaN());
93 EXPECT_EQ(0.0, diff.asAbsolute());
94 EXPECT_EQ(0U, diff.asUlps());
95 EXPECT_TRUE(diff.signsDiffer());
98 TEST(FloatingPointDifferenceTest, HandlesSignComparisonWithZero)
101 FloatingPointDifference diff(0.0, -1.2);
102 EXPECT_FALSE(diff.isNaN());
103 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
104 EXPECT_TRUE(diff.signsDiffer());
107 FloatingPointDifference diff(GMX_DOUBLE_NEGZERO, -1.2);
108 EXPECT_FALSE(diff.isNaN());
109 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
110 EXPECT_FALSE(diff.signsDiffer());
114 TEST(FloatingPointDifferenceTest, HandlesUlpDifferences)
116 const double first = 1.0;
117 const double second = addUlps(first, 2);
119 FloatingPointDifference diff(first, second);
120 EXPECT_FALSE(diff.isNaN());
121 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
122 EXPECT_EQ(2U, diff.asUlps());
123 EXPECT_FALSE(diff.signsDiffer());
126 FloatingPointDifference diff(second, first);
127 EXPECT_FALSE(diff.isNaN());
128 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
129 EXPECT_EQ(2U, diff.asUlps());
130 EXPECT_FALSE(diff.signsDiffer());
134 TEST(FloatingPointDifferenceTest, HandlesUlpDifferenceAcrossZero)
136 const double first = addUlps(GMX_DOUBLE_NEGZERO, 2);
137 const double second = addUlps(0.0, 2);
138 FloatingPointDifference diff(first, second);
139 EXPECT_FALSE(diff.isNaN());
140 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
141 EXPECT_EQ(4U, diff.asUlps());
142 EXPECT_TRUE(diff.signsDiffer());
145 TEST(FloatingPointDifferenceTest, HandlesNaN)
147 const double first = std::numeric_limits<double>::quiet_NaN();
148 const double second = 2.0;
149 FloatingPointDifference diff(first, second);
150 EXPECT_TRUE(diff.isNaN());
153 TEST(FloatingPointToleranceTest, UlpTolerance)
155 using gmx::test::ulpTolerance;
157 FloatingPointDifference fequal(1.0, 1.0);
158 FloatingPointDifference fulp2(1.0F, addUlps(1.0F, 2));
159 EXPECT_TRUE(ulpTolerance(0).isWithin(fequal));
160 EXPECT_FALSE(ulpTolerance(1).isWithin(fulp2));
161 EXPECT_TRUE(ulpTolerance(2).isWithin(fulp2));
163 FloatingPointDifference dequal(1.0, 1.0);
164 FloatingPointDifference dulp2(1.0, addUlps(1.0, 2));
165 FloatingPointDifference dulp2f(1.0, static_cast<double>(addUlps(1.0F, 2)));
166 EXPECT_TRUE(ulpTolerance(0).isWithin(dequal));
167 EXPECT_TRUE(ulpTolerance(2).isWithin(dulp2));
168 EXPECT_FALSE(ulpTolerance(2).isWithin(dulp2f));
171 TEST(FloatingPointToleranceTest, RelativeToleranceAsFloatingPoint)
173 using gmx::test::relativeToleranceAsFloatingPoint;
175 FloatingPointDifference fequal(1.0F, 1.0F);
176 FloatingPointDifference fulp2(1.0F, addUlps(1.0F, 2));
177 FloatingPointDifference fdiff(1.0F, 1.011F);
178 FloatingPointDifference fsmall(0.1F, 0.111F);
179 FloatingPointDifference fsmall2(0.1F, 0.121F);
180 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(fequal));
181 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-9).isWithin(fequal));
182 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(fulp2));
183 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 1e-9).isWithin(fulp2));
184 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(fdiff));
185 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(fdiff));
186 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(fsmall));
187 EXPECT_FALSE(relativeToleranceAsFloatingPoint(0.1, 2e-2).isWithin(fsmall));
188 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(fsmall2));
190 FloatingPointDifference dequal(1.0, 1.0);
191 FloatingPointDifference dulp2f(1.0, static_cast<double>(addUlps(1.0F, 2)));
192 FloatingPointDifference ddiff(1.0, 1.011);
193 FloatingPointDifference dsmall(0.1, 0.111);
194 FloatingPointDifference dsmall2(0.1, 0.121);
195 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(dequal));
196 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-9).isWithin(dequal));
197 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(dulp2f));
198 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 1e-9).isWithin(dulp2f));
199 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 1e-2).isWithin(ddiff));
200 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(ddiff));
201 EXPECT_TRUE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(dsmall));
202 EXPECT_FALSE(relativeToleranceAsFloatingPoint(0.1, 2e-2).isWithin(dsmall));
203 EXPECT_FALSE(relativeToleranceAsFloatingPoint(1.0, 2e-2).isWithin(dsmall2));
206 TEST(FloatingPointToleranceTest, RelativeToleranceAsUlp)
208 using gmx::test::relativeToleranceAsUlp;
210 FloatingPointDifference fequal(1.0F, 1.0F);
211 FloatingPointDifference fulp4(1.0F, addUlps(1.0F, 4));
212 FloatingPointDifference fsmall(0.1F, addUlps(1.0F, 2) - 0.9F);
213 FloatingPointDifference fsmall2(0.1F, addUlps(1.0F, 6) - 0.9F);
214 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 2).isWithin(fequal));
215 EXPECT_FALSE(relativeToleranceAsUlp(1.0, 2).isWithin(fulp4));
216 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 4).isWithin(fulp4));
217 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 4).isWithin(fsmall));
218 EXPECT_FALSE(relativeToleranceAsUlp(0.1, 4).isWithin(fsmall));
219 EXPECT_FALSE(relativeToleranceAsUlp(1.0, 4).isWithin(fsmall2));
221 FloatingPointDifference dequal(1.0, 1.0);
222 FloatingPointDifference dulp4(1.0, addUlps(1.0, 4));
223 FloatingPointDifference dulp4f(1.0, static_cast<double>(addUlps(1.0F, 4)));
224 FloatingPointDifference dsmall(0.1, addUlps(1.0, 2) - 0.9);
225 FloatingPointDifference dsmall2(0.1, addUlps(1.0, 6) - 0.9);
226 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 2).isWithin(dequal));
227 EXPECT_FALSE(relativeToleranceAsUlp(1.0, 2).isWithin(dulp4));
228 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 4).isWithin(dulp4));
229 EXPECT_FALSE(relativeToleranceAsUlp(1.0, 4).isWithin(dulp4f));
230 EXPECT_TRUE(relativeToleranceAsUlp(1.0, 4).isWithin(dsmall));
231 EXPECT_FALSE(relativeToleranceAsUlp(0.1, 4).isWithin(dsmall));
232 EXPECT_FALSE(relativeToleranceAsUlp(1.0, 4).isWithin(dsmall2));
235 TEST(FloatingPointToleranceTest, DefaultFloatTolerance)
237 using gmx::test::defaultFloatTolerance;
239 // Differences within 4 single-precision ULPs are within the tolerance
240 FloatingPointDifference fequal(1.0F, 1.0F);
241 FloatingPointDifference fulp4(1.0F, addUlps(1.0F, 4));
242 FloatingPointDifference fulp8(1.0F, addUlps(1.0F, 8));
243 FloatingPointDifference fsmall(0.1F, addUlps(1.0F, 2) - 0.9F);
244 FloatingPointDifference fsmall2(0.1F, addUlps(1.0F, 6) - 0.9F);
245 EXPECT_TRUE(defaultFloatTolerance().isWithin(fequal));
246 EXPECT_TRUE(defaultFloatTolerance().isWithin(fulp4));
247 EXPECT_FALSE(defaultFloatTolerance().isWithin(fulp8));
248 EXPECT_TRUE(defaultFloatTolerance().isWithin(fsmall));
249 EXPECT_FALSE(defaultFloatTolerance().isWithin(fsmall2));
251 // Differences within 4 single-precision ULPs are still within the
252 // tolerance, even when expressed as double-precision values.
253 FloatingPointDifference dequal(1.0, 1.0);
254 FloatingPointDifference dulp4(1.0, addUlps(1.0, 4));
255 FloatingPointDifference dulp8(1.0, addUlps(1.0, 8));
256 FloatingPointDifference dulp4f(1.0, static_cast<double>(addUlps(1.0F, 4)));
257 FloatingPointDifference dulp8f(1.0, static_cast<double>(addUlps(1.0F, 8)));
258 FloatingPointDifference dsmallf(0.1, static_cast<double>(addUlps(1.0F, 2) - 0.9F));
259 FloatingPointDifference dsmall2f(0.1, static_cast<double>(addUlps(1.0F, 6) - 0.9F));
260 EXPECT_TRUE(defaultFloatTolerance().isWithin(dequal));
261 EXPECT_TRUE(defaultFloatTolerance().isWithin(dulp4));
262 EXPECT_TRUE(defaultFloatTolerance().isWithin(dulp8));
263 EXPECT_TRUE(defaultFloatTolerance().isWithin(dulp4f));
264 EXPECT_FALSE(defaultFloatTolerance().isWithin(dulp8f));
265 EXPECT_TRUE(defaultFloatTolerance().isWithin(dsmallf));
266 EXPECT_FALSE(defaultFloatTolerance().isWithin(dsmall2f));