1 /*
2  * Copyright © 2015 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  */
24 
25 #include "igt_core.h"
26 #include "igt_stats.h"
27 
28 #define ARRAY_SIZE(arr) (sizeof(arr)/sizeof(arr[0]))
29 
push_fixture_1(igt_stats_t * stats)30 static void push_fixture_1(igt_stats_t *stats)
31 {
32 	igt_stats_push(stats, 2);
33 	igt_stats_push(stats, 4);
34 	igt_stats_push(stats, 6);
35 	igt_stats_push(stats, 8);
36 	igt_stats_push(stats, 10);
37 }
38 
39 /* Make sure we zero igt_stats_t fields at init() time */
test_init_zero(void)40 static void test_init_zero(void)
41 {
42 	igt_stats_t stats;
43 
44 	stats.mean = 1.;
45 	igt_stats_init(&stats);
46 	igt_assert_eq_double(stats.mean, 0.);
47 }
48 
test_init(void)49 static void test_init(void)
50 {
51 	igt_stats_t stats;
52 
53 	igt_stats_init(&stats);
54 
55 	/*
56 	 * Make sure we default to representing only a sample of a bigger
57 	 * population.
58 	 */
59 	igt_assert(igt_stats_is_population(&stats) == false);
60 }
61 
test_min_max(void)62 static void test_min_max(void)
63 {
64 	igt_stats_t stats;
65 
66 	igt_stats_init(&stats);
67 	push_fixture_1(&stats);
68 
69 	igt_assert(igt_stats_get_min(&stats) == 2);
70 	igt_assert(igt_stats_get_max(&stats) == 10);
71 }
72 
test_range(void)73 static void test_range(void)
74 {
75 	igt_stats_t stats;
76 
77 	igt_stats_init(&stats);
78 	push_fixture_1(&stats);
79 
80 	igt_assert(igt_stats_get_range(&stats) == 8);
81 }
82 
83 /*
84  * Examples taken from: https://en.wikipedia.org/wiki/Quartile
85  * The values are shifted a bit to test we do indeed start by sorting data
86  * set.
87  */
test_quartiles(void)88 static void test_quartiles(void)
89 {
90 	static const uint64_t s1[] =
91 		{ 47, 49, 6, 7, 15, 36, 39, 40, 41, 42, 43 };
92 	static const uint64_t s2[] = { 40, 41, 7, 15, 36, 39 };
93 	igt_stats_t stats;
94 	double q1, q2, q3;
95 
96 	/* s1, odd number of data points */
97 	igt_stats_init(&stats);
98 	igt_stats_push_array(&stats, s1, ARRAY_SIZE(s1));
99 
100 	igt_stats_get_quartiles(&stats, &q1, &q2, &q3);
101 	igt_assert_eq_double(q1, 25.5);
102 	igt_assert_eq_double(q2, 40);
103 	igt_assert_eq_double(q3, 42.5);
104 	igt_assert_eq_double(igt_stats_get_median(&stats), 40);
105 	igt_assert_eq_double(igt_stats_get_iqr(&stats), 42.5 - 25.5);
106 
107 	igt_stats_fini(&stats);
108 
109 	/* s1, even number of data points */
110 	igt_stats_init(&stats);
111 	igt_stats_push_array(&stats, s2, ARRAY_SIZE(s2));
112 
113 	igt_stats_get_quartiles(&stats, &q1, &q2, &q3);
114 	igt_assert_eq_double(q1, 15);
115 	igt_assert_eq_double(q2, 37.5);
116 	igt_assert_eq_double(q3, 40);
117 	igt_assert_eq_double(igt_stats_get_median(&stats), 37.5);
118 	igt_assert_eq_double(igt_stats_get_iqr(&stats), 40 - 15);
119 
120 	igt_stats_fini(&stats);
121 }
122 
test_invalidate_sorted(void)123 static void test_invalidate_sorted(void)
124 {
125 	igt_stats_t stats;
126 	static const uint64_t s1_truncated[] =
127 		{ 47, 49, 6, 7, 15, 36, 39, 40, 41, 42};
128 	double median1, median2;
129 
130 	igt_stats_init(&stats);
131 	igt_stats_push_array(&stats, s1_truncated, ARRAY_SIZE(s1_truncated));
132 	median1 = igt_stats_get_median(&stats);
133 
134 	igt_stats_push(&stats, 43);
135 	median2 = igt_stats_get_median(&stats);
136 
137 	igt_assert_eq_double(median2, 40);
138 	igt_assert(median1 != median2);
139 }
140 
test_mean(void)141 static void test_mean(void)
142 {
143 	igt_stats_t stats;
144 	double mean;
145 
146 	igt_stats_init(&stats);
147 	push_fixture_1(&stats);
148 
149 	mean = igt_stats_get_mean(&stats);
150 	igt_assert_eq_double(mean, (2 + 4 + 6 + 8 + 10) / 5.);
151 
152 	igt_stats_fini(&stats);
153 }
154 
test_invalidate_mean(void)155 static void test_invalidate_mean(void)
156 {
157 	igt_stats_t stats;
158 	double mean1, mean2;
159 
160 	igt_stats_init(&stats);
161 	push_fixture_1(&stats);
162 
163 	mean1 = igt_stats_get_mean(&stats);
164 	igt_assert_eq_double(mean1, (2 + 4 + 6 + 8 + 10) / 5.);
165 
166 	igt_stats_push(&stats, 100);
167 
168 	mean2 = igt_stats_get_mean(&stats);
169 	igt_assert(mean1 != mean2);
170 
171 	igt_stats_fini(&stats);
172 }
173 
174 /*
175  * Taken from the "Basic examples" section of:
176  * https://en.wikipedia.org/wiki/Standard_deviation
177  */
test_std_deviation(void)178 static void test_std_deviation(void)
179 {
180 	igt_stats_t stats;
181 	double mean, variance, std_deviation;
182 
183 	igt_stats_init(&stats);
184 	igt_stats_set_population(&stats, true);
185 
186 	igt_stats_push(&stats, 2);
187 	igt_stats_push(&stats, 4);
188 	igt_stats_push(&stats, 4);
189 	igt_stats_push(&stats, 4);
190 	igt_stats_push(&stats, 5);
191 	igt_stats_push(&stats, 5);
192 	igt_stats_push(&stats, 7);
193 	igt_stats_push(&stats, 9);
194 
195 	mean = igt_stats_get_mean(&stats);
196 	igt_assert_eq_double(mean, (2 + 3 * 4 + 2 * 5 + 7 + 9) / 8.);
197 
198 	variance = igt_stats_get_variance(&stats);
199 	igt_assert_eq_double(variance, 4);
200 
201 	std_deviation = igt_stats_get_std_deviation(&stats);
202 	igt_assert_eq_double(std_deviation, 2);
203 
204 	igt_stats_fini(&stats);
205 }
206 
test_reallocation(void)207 static void test_reallocation(void)
208 {
209 	igt_stats_t stats;
210 	unsigned int i;
211 
212 	igt_stats_init_with_size(&stats, 1);
213 
214 	for (i = 0; i < 101; i++) {
215 		igt_stats_push(&stats, i);
216 		/* also triggers ->sorted reallocations */
217 		if (i > 10)
218 			igt_stats_get_median(&stats);
219 	}
220 	igt_assert(!stats.is_float);
221 
222 	igt_assert_eq(stats.n_values, 101);
223 	for (i = 0; i < 101; i++)
224 		igt_assert_eq(stats.values_u64[i], i);
225 	igt_assert_eq_double(igt_stats_get_mean(&stats), 50.0);
226 	igt_assert_eq_double(igt_stats_get_median(&stats), 50.0);
227 
228 	igt_stats_fini(&stats);
229 }
230 
231 igt_simple_main
232 {
233 	test_init_zero();
234 	test_init();
235 	test_min_max();
236 	test_range();
237 	test_quartiles();
238 	test_invalidate_sorted();
239 	test_mean();
240 	test_invalidate_mean();
241 	test_std_deviation();
242 	test_reallocation();
243 }
244