1// Licensed to the .NET Foundation under one or more agreements.
2// The .NET Foundation licenses this file to you under the MIT license.
3// See the LICENSE file in the project root for more information.
4
5/*=====================================================================
6**
7** Source: test1.c
8**
9** Purpose: Tests that atan2f returns correct values for a subset of values.
10** Tests with positive and negative values of x and y to ensure
11** atan2f is returning results from the correct quadrant.
12**
13**===================================================================*/
14
15#include <palsuite.h>
16
17// binary32 (float) has a machine epsilon of 2^-23 (approx. 1.19e-07). However, this
18// is slightly too accurate when writing tests meant to run against libm implementations
19// for various platforms. 2^-21 (approx. 4.76e-07) seems to be as accurate as we can get.
20//
21// The tests themselves will take PAL_EPSILON and adjust it according to the expected result
22// so that the delta used for comparison will compare the most significant digits and ignore
23// any digits that are outside the double precision range (6-9 digits).
24
25// For example, a test with an expect result in the format of 0.xxxxxxxxx will use PAL_EPSILON
26// for the variance, while an expected result in the format of 0.0xxxxxxxxx will use
27// PAL_EPSILON / 10 and and expected result in the format of x.xxxxxx will use PAL_EPSILON * 10.
28#define PAL_EPSILON 4.76837158e-07
29
30#define PAL_NAN sqrtf(-1.0f)
31#define PAL_POSINF -logf(0.0f)
32#define PAL_NEGINF logf(0.0f)
33
34/**
35 * Helper test structure
36 */
37struct test
38{
39 float x; /* first component of the value to test the function with */
40 float y; /* second component of the value to test the function with */
41 float expected; /* expected result */
42 float variance; /* maximum delta between the expected and actual result */
43};
44
45/**
46 * validate
47 *
48 * test validation function
49 */
50void __cdecl validate(float x, float y, float expected, float variance)
51{
52 float result = powf(x, y);
53
54 /*
55 * The test is valid when the difference between result
56 * and expected is less than or equal to variance
57 */
58 float delta = fabsf(result - expected);
59
60 if (delta > variance)
61 {
62 Fail("powf(%g, %g) returned %10.9g when it should have returned %10.9g",
63 x, y, result, expected);
64 }
65}
66
67/**
68 * validate
69 *
70 * test validation function for values returning NaN
71 */
72void __cdecl validate_isnan(float x, float y)
73{
74 float result = powf(x, y);
75
76 if (!_isnanf(result))
77 {
78 Fail("powf(%g, %g) returned %10.9g when it should have returned %10.9g",
79 x, y, result, PAL_NAN);
80 }
81}
82
83/**
84 * main
85 *
86 * executable entry point
87 */
88int __cdecl main(int argc, char **argv)
89{
90 struct test tests[] =
91 {
92 /* x y expected variance */
93 { PAL_NEGINF, PAL_NEGINF, 0, PAL_EPSILON },
94 { PAL_NEGINF, PAL_POSINF, PAL_POSINF, 0 },
95
96 { -10, PAL_NEGINF, 0, PAL_EPSILON },
97 { -10, -1, -0.1f, PAL_EPSILON },
98 { -10, 0, 1, PAL_EPSILON * 10 },
99 { -10, 1, -10, PAL_EPSILON * 100 },
100 { -10, PAL_POSINF, PAL_POSINF, 0 },
101
102 { -2.71828183f, PAL_NEGINF, 0, PAL_EPSILON }, // x: -(e)
103 { -2.71828183f, -1, -0.367879441f, PAL_EPSILON }, // x: -(e)
104 { -2.71828183f, 0, 1, PAL_EPSILON * 10 }, // x: -(e)
105 { -2.71828183f, 1, -2.71828183f, PAL_EPSILON * 10 }, // x: -(e) expected: e
106 { -2.71828183f, PAL_POSINF, PAL_POSINF, 0 }, // x: -(e)
107
108 { -1.0, PAL_NEGINF, 1.0, PAL_EPSILON * 10 },
109 { -1.0, PAL_POSINF, 1.0, PAL_EPSILON * 10 },
110
111 { -0.0, PAL_NEGINF, PAL_POSINF, 0 },
112 { -0.0, -1, PAL_NEGINF, 0 },
113 { -0.0f, -0.0f, 1, PAL_EPSILON * 10 },
114 { -0.0f, 0, 1, PAL_EPSILON * 10 },
115 { -0.0, 1, -0.0, PAL_EPSILON },
116 { -0.0, PAL_POSINF, 0, PAL_EPSILON },
117
118 { PAL_NAN, -0.0, 1.0, PAL_EPSILON * 10 },
119 { PAL_NAN, 0, 1.0, PAL_EPSILON * 10 },
120
121 { 0.0, PAL_NEGINF, PAL_POSINF, 0 },
122 { 0.0, -1, PAL_POSINF, 0 },
123 { 0, -0.0f, 1, PAL_EPSILON * 10 },
124 { 0, 0, 1, PAL_EPSILON * 10 },
125 { 0.0, 1, 0, PAL_EPSILON },
126 { 0.0, PAL_POSINF, 0, PAL_EPSILON },
127
128 { 1, PAL_NEGINF, 1, PAL_EPSILON * 10 },
129 { 1, PAL_POSINF, 1, PAL_EPSILON * 10 },
130
131 { 2.71828183f, PAL_NEGINF, 0, PAL_EPSILON },
132 { 2.71828183f, -3.14159265f, 0.0432139183f, PAL_EPSILON / 10 }, // x: e y: -(pi)
133 { 2.71828183f, -2.71828183f, 0.0659880358f, PAL_EPSILON / 10 }, // x: e y: -(e)
134 { 2.71828183f, -2.30258509f, 0.1f, PAL_EPSILON }, // x: e y: -(ln(10))
135 { 2.71828183f, -1.57079633f, 0.207879576f, PAL_EPSILON }, // x: e y: -(pi / 2)
136 { 2.71828183f, -1.44269504f, 0.236290088f, PAL_EPSILON }, // x: e y: -(logf2(e))
137 { 2.71828183f, -1.41421356f, 0.243116734f, PAL_EPSILON }, // x: e y: -(sqrtf(2))
138 { 2.71828183f, -1.12837917f, 0.323557264f, PAL_EPSILON }, // x: e y: -(2 / sqrtf(pi))
139 { 2.71828183f, -1, 0.367879441f, PAL_EPSILON }, // x: e y: -(1)
140 { 2.71828183f, -0.785398163f, 0.455938128f, PAL_EPSILON }, // x: e y: -(pi / 4)
141 { 2.71828183f, -0.707106781f, 0.493068691f, PAL_EPSILON }, // x: e y: -(1 / sqrtf(2))
142 { 2.71828183f, -0.693147181f, 0.5f, PAL_EPSILON }, // x: e y: -(ln(2))
143 { 2.71828183f, -0.636619772f, 0.529077808f, PAL_EPSILON }, // x: e y: -(2 / pi)
144 { 2.71828183f, -0.434294482f, 0.647721485f, PAL_EPSILON }, // x: e y: -(log10f(e))
145 { 2.71828183f, -0.318309886f, 0.727377349f, PAL_EPSILON }, // x: e y: -(1 / pi)
146 { 2.71828183f, 0, 1, PAL_EPSILON * 10 }, // x: e
147 { 2.71828183f, 0.318309886f, 1.37480223f, PAL_EPSILON * 10 }, // x: e y: 1 / pi
148 { 2.71828183f, 0.434294482f, 1.54387344f, PAL_EPSILON * 10 }, // x: e y: log10f(e)
149 { 2.71828183f, 0.636619772f, 1.89008116f, PAL_EPSILON * 10 }, // x: e y: 2 / pi
150 { 2.71828183f, 0.693147181f, 2, PAL_EPSILON * 10 }, // x: e y: ln(2)
151 { 2.71828183f, 0.707106781f, 2.02811498f, PAL_EPSILON * 10 }, // x: e y: 1 / sqrtf(2)
152 { 2.71828183f, 0.785398163f, 2.19328005f, PAL_EPSILON * 10 }, // x: e y: pi / 4
153 { 2.71828183f, 1, 2.71828183f, PAL_EPSILON * 10 }, // x: e expected: e
154 { 2.71828183f, 1.12837917f, 3.09064302f, PAL_EPSILON * 10 }, // x: e y: 2 / sqrtf(pi)
155 { 2.71828183f, 1.41421356f, 4.11325038f, PAL_EPSILON * 10 }, // x: e y: sqrtf(2)
156 { 2.71828183f, 1.44269504f, 4.23208611f, PAL_EPSILON * 10 }, // x: e y: logf2(e)
157 { 2.71828183f, 1.57079633f, 4.81047738f, PAL_EPSILON * 10 }, // x: e y: pi / 2
158 { 2.71828183f, 2.30258509f, 10, PAL_EPSILON * 100 }, // x: e y: ln(10)
159 { 2.71828183f, 2.71828183f, 15.1542622f, PAL_EPSILON * 100 }, // x: e y: e
160 { 2.71828183f, 3.14159265f, 23.1406926f, PAL_EPSILON * 100 }, // x: e y: pi
161 { 2.71828183f, PAL_POSINF, PAL_POSINF, 0 }, // x: e
162
163 { 10, PAL_NEGINF, 0, 0 },
164 { 10, -3.14159265f, 0.000721784159f, PAL_EPSILON / 1000 }, // y: -(pi)
165 { 10, -2.71828183f, 0.00191301410f, PAL_EPSILON / 100 }, // y: -(e)
166 { 10, -2.30258509f, 0.00498212830f, PAL_EPSILON / 100 }, // y: -(ln(10))
167 { 10, -1.57079633f, 0.0268660410f, PAL_EPSILON / 10 }, // y: -(pi / 2)
168 { 10, -1.44269504f, 0.0360831928f, PAL_EPSILON / 10 }, // y: -(logf2(e))
169 { 10, -1.41421356f, 0.0385288847f, PAL_EPSILON / 10 }, // y: -(sqrtf(2))
170 { 10, -1.12837917f, 0.0744082059f, PAL_EPSILON / 10 }, // y: -(2 / sqrtf(pi))
171 { 10, -1, 0.1f, PAL_EPSILON }, // y: -(1)
172 { 10, -0.785398163f, 0.163908636f, PAL_EPSILON }, // y: -(pi / 4)
173 { 10, -0.707106781f, 0.196287760f, PAL_EPSILON }, // y: -(1 / sqrtf(2))
174 { 10, -0.693147181f, 0.202699566f, PAL_EPSILON }, // y: -(ln(2))
175 { 10, -0.636619772f, 0.230876765f, PAL_EPSILON }, // y: -(2 / pi)
176 { 10, -0.434294482f, 0.367879441f, PAL_EPSILON }, // y: -(log10f(e))
177 { 10, -0.318309886f, 0.480496373f, PAL_EPSILON }, // y: -(1 / pi)
178 { 10, 0, 1, PAL_EPSILON * 10 },
179 { 10, 0.318309886f, 2.08118116f, PAL_EPSILON * 10 }, // y: 1 / pi
180 { 10, 0.434294482f, 2.71828183f, PAL_EPSILON * 10 }, // y: log10f(e) expected: e
181 { 10, 0.636619772f, 4.33131503f, PAL_EPSILON * 10 }, // y: 2 / pi
182 { 10, 0.693147181f, 4.93340967f, PAL_EPSILON * 10 }, // y: ln(2)
183 { 10, 0.707106781f, 5.09456117f, PAL_EPSILON * 10 }, // y: 1 / sqrtf(2)
184 { 10, 0.785398163f, 6.10095980f, PAL_EPSILON * 10 }, // y: pi / 4
185 { 10, 1, 10, PAL_EPSILON * 100 },
186 { 10, 1.12837917f, 13.4393779f, PAL_EPSILON * 100 }, // y: 2 / sqrtf(pi)
187 { 10, 1.41421356f, 25.9545535f, PAL_EPSILON * 100 }, // y: sqrtf(2)
188 { 10, 1.44269504f, 27.7137338f, PAL_EPSILON * 100 }, // y: logf2(e)
189 { 10, 1.57079633f, 37.2217105f, PAL_EPSILON * 100 }, // y: pi / 2
190 { 10, 2.30258509f, 200.717432f, PAL_EPSILON * 1000 }, // y: ln(10)
191 { 10, 2.71828183f, 522.735300f, PAL_EPSILON * 1000 }, // y: e
192 { 10, 3.14159265f, 1385.45573f, PAL_EPSILON * 10000 }, // y: pi
193 { 10, PAL_POSINF, PAL_POSINF, 0 },
194
195 { PAL_POSINF, PAL_NEGINF, 0, PAL_EPSILON },
196 { PAL_POSINF, PAL_POSINF, PAL_POSINF, 0 },
197 };
198
199 if (PAL_Initialize(argc, argv) != 0)
200 {
201 return FAIL;
202 }
203
204 for (int i = 0; i < (sizeof(tests) / sizeof(struct test)); i++)
205 {
206 validate(tests[i].x, tests[i].y, tests[i].expected, tests[i].variance);
207 }
208
209 validate_isnan(-10, -1.57079633f); // y: -(pi / 2)
210 validate_isnan(-10, -0.785398163f); // y: -(pi / 4)
211 validate_isnan(-10, 0.785398163f); // y: pi / 4
212 validate_isnan(-10, 1.57079633f); // y: pi / 2
213
214 validate_isnan(-2.71828183f, -1.57079633f); // x: -(e) y: -(pi / 2)
215 validate_isnan(-2.71828183f, -0.785398163f); // x: -(e) y: -(pi / 4)
216 validate_isnan(-2.71828183f, 0.785398163f); // x: -(e) y: pi / 4
217 validate_isnan(-2.71828183f, 1.57079633f); // x: -(e) y: pi / 2
218
219 validate_isnan(PAL_NEGINF, PAL_NAN);
220 validate_isnan(PAL_NAN, PAL_NEGINF);
221
222 validate_isnan(PAL_POSINF, PAL_NAN);
223 validate_isnan(PAL_NAN, PAL_POSINF);
224
225 validate_isnan(PAL_NAN, PAL_NAN);
226
227 PAL_Terminate();
228 return PASS;
229}
230