34 #define sorted_value(stats, i) (stats->is_float ? stats->sorted_f[i] : stats->sorted_u64[i])  argument
35 #define unsorted_value(stats, i) (stats->is_float ? stats->values_f[i] : stats->values_u64[i])  argument
40  * @title: Stats
50  *	igt_stats_t stats;
52  *	igt_stats_init(&stats, 8);
54  *	igt_stats_push(&stats, 2);
55  *	igt_stats_push(&stats, 4);
56  *	igt_stats_push(&stats, 4);
57  *	igt_stats_push(&stats, 4);
58  *	igt_stats_push(&stats, 5);
59  *	igt_stats_push(&stats, 5);
60  *	igt_stats_push(&stats, 7);
61  *	igt_stats_push(&stats, 9);
63  *	printf("Mean: %lf\n", igt_stats_get_mean(&stats));
65  *	igt_stats_fini(&stats);
80 static void igt_stats_ensure_capacity(igt_stats_t *stats,  in igt_stats_ensure_capacity()  argument
83 	unsigned int new_n_values = stats->n_values + n_additional_values;  in igt_stats_ensure_capacity()
86 	if (new_n_values <= stats->capacity)  in igt_stats_ensure_capacity()
90 	stats->values_u64 = realloc(stats->values_u64,  in igt_stats_ensure_capacity()
91 				    sizeof(*stats->values_u64) * new_capacity);  in igt_stats_ensure_capacity()
92 	igt_assert(stats->values_u64);  in igt_stats_ensure_capacity()
94 	stats->capacity = new_capacity;  in igt_stats_ensure_capacity()
96 	free(stats->sorted_u64);  in igt_stats_ensure_capacity()
97 	stats->sorted_u64 = NULL;  in igt_stats_ensure_capacity()
102  * @stats: An #igt_stats_t instance
105  * finished with @stats.
107 void igt_stats_init(igt_stats_t *stats)  in igt_stats_init()  argument
109 	memset(stats, 0, sizeof(*stats));  in igt_stats_init()
111 	igt_stats_ensure_capacity(stats, 128);  in igt_stats_init()
113 	stats->min = U64_MAX;  in igt_stats_init()
114 	stats->max = 0;  in igt_stats_init()
119  * @stats: An #igt_stats_t instance
120  * @capacity: Number of data samples @stats can contain
124  * number of data points we want @stats to hold.
126  * igt_stats_fini() must be called once finished with @stats.
128 void igt_stats_init_with_size(igt_stats_t *stats, unsigned int capacity)  in igt_stats_init_with_size()  argument
130 	memset(stats, 0, sizeof(*stats));  in igt_stats_init_with_size()
132 	igt_stats_ensure_capacity(stats, capacity);  in igt_stats_init_with_size()
134 	stats->min = U64_MAX;  in igt_stats_init_with_size()
135 	stats->max = 0;  in igt_stats_init_with_size()
136 	stats->range[0] = HUGE_VAL;  in igt_stats_init_with_size()
137 	stats->range[1] = -HUGE_VAL;  in igt_stats_init_with_size()
142  * @stats: An #igt_stats_t instance
146 void igt_stats_fini(igt_stats_t *stats)  in igt_stats_fini()  argument
148 	free(stats->values_u64);  in igt_stats_fini()
149 	free(stats->sorted_u64);  in igt_stats_fini()
155  * @stats: An #igt_stats_t instance
157  * Returns: #true if @stats represents a population, #false if only a sample.
161 bool igt_stats_is_population(igt_stats_t *stats)  in igt_stats_is_population()  argument
163 	return stats->is_population;  in igt_stats_is_population()
168  * @stats: An #igt_stats_t instance
187  * When giving #true to this function, the data set in @stats is considered a
190  * When newly created, @stats defaults to holding sample data.
192 void igt_stats_set_population(igt_stats_t *stats, bool full_population)  in igt_stats_set_population()  argument
194 	if (full_population == stats->is_population)  in igt_stats_set_population()
197 	stats->is_population = full_population;  in igt_stats_set_population()
198 	stats->mean_variance_valid = false;  in igt_stats_set_population()
203  * @stats: An #igt_stats_t instance
206  * Adds a new value to the @stats dataset.
208 void igt_stats_push(igt_stats_t *stats, uint64_t value)  in igt_stats_push()  argument
210 	if (stats->is_float) {  in igt_stats_push()
211 		igt_stats_push_float(stats, value);  in igt_stats_push()
215 	igt_stats_ensure_capacity(stats, 1);  in igt_stats_push()
217 	stats->values_u64[stats->n_values++] = value;  in igt_stats_push()
219 	stats->mean_variance_valid = false;  in igt_stats_push()
220 	stats->sorted_array_valid = false;  in igt_stats_push()
222 	if (value < stats->min)  in igt_stats_push()
223 		stats->min = value;  in igt_stats_push()
224 	if (value > stats->max)  in igt_stats_push()
225 		stats->max = value;  in igt_stats_push()
230  * @stats: An #igt_stats_t instance
233  * Adds a new value to the @stats dataset and converts the igt_stats from
236 void igt_stats_push_float(igt_stats_t *stats, double value)  in igt_stats_push_float()  argument
238 	igt_stats_ensure_capacity(stats, 1);  in igt_stats_push_float()
240 	if (!stats->is_float) {  in igt_stats_push_float()
243 		for (n = 0; n < stats->n_values; n++)  in igt_stats_push_float()
244 			stats->values_f[n] = stats->values_u64[n];  in igt_stats_push_float()
246 		stats->is_float = true;  in igt_stats_push_float()
249 	stats->values_f[stats->n_values++] = value;  in igt_stats_push_float()
251 	stats->mean_variance_valid = false;  in igt_stats_push_float()
252 	stats->sorted_array_valid = false;  in igt_stats_push_float()
254 	if (value < stats->range[0])  in igt_stats_push_float()
255 		stats->range[0] = value;  in igt_stats_push_float()
256 	if (value > stats->range[1])  in igt_stats_push_float()
257 		stats->range[1] = value;  in igt_stats_push_float()
262  * @stats: An #igt_stats_t instance
266  * Adds an array of values to the @stats dataset.
268 void igt_stats_push_array(igt_stats_t *stats,  in igt_stats_push_array()  argument
273 	igt_stats_ensure_capacity(stats, n_values);  in igt_stats_push_array()
276 		igt_stats_push(stats, values[i]);  in igt_stats_push_array()
281  * @stats: An #igt_stats_t instance
283  * Retrieves the minimal value in @stats
285 uint64_t igt_stats_get_min(igt_stats_t *stats)  in igt_stats_get_min()  argument
287 	igt_assert(!stats->is_float);  in igt_stats_get_min()
288 	return stats->min;  in igt_stats_get_min()
293  * @stats: An #igt_stats_t instance
295  * Retrieves the maximum value in @stats
297 uint64_t igt_stats_get_max(igt_stats_t *stats)  in igt_stats_get_max()  argument
299 	igt_assert(!stats->is_float);  in igt_stats_get_max()
300 	return stats->max;  in igt_stats_get_max()
305  * @stats: An #igt_stats_t instance
307  * Retrieves the range of the values in @stats. The range is the difference
314 uint64_t igt_stats_get_range(igt_stats_t *stats)  in igt_stats_get_range()  argument
316 	return igt_stats_get_max(stats) - igt_stats_get_min(stats);  in igt_stats_get_range()
341 static void igt_stats_ensure_sorted_values(igt_stats_t *stats)  in igt_stats_ensure_sorted_values()  argument
343 	if (stats->sorted_array_valid)  in igt_stats_ensure_sorted_values()
346 	if (!stats->sorted_u64) {  in igt_stats_ensure_sorted_values()
353 		stats->sorted_u64 = calloc(stats->capacity,  in igt_stats_ensure_sorted_values()
354 					   sizeof(*stats->values_u64));  in igt_stats_ensure_sorted_values()
355 		igt_assert(stats->sorted_u64);  in igt_stats_ensure_sorted_values()
358 	memcpy(stats->sorted_u64, stats->values_u64,  in igt_stats_ensure_sorted_values()
359 	       sizeof(*stats->values_u64) * stats->n_values);  in igt_stats_ensure_sorted_values()
361 	qsort(stats->sorted_u64, stats->n_values, sizeof(*stats->values_u64),  in igt_stats_ensure_sorted_values()
362 	      stats->is_float ? cmp_f : cmp_u64);  in igt_stats_ensure_sorted_values()
364 	stats->sorted_array_valid = true;  in igt_stats_ensure_sorted_values()
372 igt_stats_get_median_internal(igt_stats_t *stats,  in igt_stats_get_median_internal()  argument
380 	igt_stats_ensure_sorted_values(stats);  in igt_stats_get_median_internal()
386 		median = sorted_value(stats, mid);  in igt_stats_get_median_internal()
402 		median = (sorted_value(stats, mid) + sorted_value(stats, mid+1))/2.;  in igt_stats_get_median_internal()
415  * @stats: An #igt_stats_t instance
421  * @stats dataset.
423 void igt_stats_get_quartiles(igt_stats_t *stats,  in igt_stats_get_quartiles()  argument
429 	if (stats->n_values < 3) {  in igt_stats_get_quartiles()
439 	ret = igt_stats_get_median_internal(stats, 0, stats->n_values,  in igt_stats_get_quartiles()
444 	ret = igt_stats_get_median_internal(stats, 0, lower_end, NULL, NULL);  in igt_stats_get_quartiles()
448 	ret = igt_stats_get_median_internal(stats, upper_start, stats->n_values,  in igt_stats_get_quartiles()
456  * @stats: An #igt_stats_t instance
460  * (IQR) of the @stats dataset.
462 double igt_stats_get_iqr(igt_stats_t *stats)  in igt_stats_get_iqr()  argument
466 	igt_stats_get_quartiles(stats, &q1, NULL, &q3);  in igt_stats_get_iqr()
472  * @stats: An #igt_stats_t instance
474  * Retrieves the median of the @stats dataset.
476 double igt_stats_get_median(igt_stats_t *stats)  in igt_stats_get_median()  argument
478 	return igt_stats_get_median_internal(stats, 0, stats->n_values,  in igt_stats_get_median()
490 static void igt_stats_knuth_mean_variance(igt_stats_t *stats)  in igt_stats_knuth_mean_variance()  argument
495 	if (stats->mean_variance_valid)  in igt_stats_knuth_mean_variance()
498 	for (i = 0; i < stats->n_values; i++) {  in igt_stats_knuth_mean_variance()
499 		double delta = unsorted_value(stats, i) - mean;  in igt_stats_knuth_mean_variance()
502 		m2 += delta * (unsorted_value(stats, i) - mean);  in igt_stats_knuth_mean_variance()
505 	stats->mean = mean;  in igt_stats_knuth_mean_variance()
506 	if (stats->n_values > 1 && !stats->is_population)  in igt_stats_knuth_mean_variance()
507 		stats->variance = m2 / (stats->n_values - 1);  in igt_stats_knuth_mean_variance()
509 		stats->variance = m2 / stats->n_values;  in igt_stats_knuth_mean_variance()
510 	stats->mean_variance_valid = true;  in igt_stats_knuth_mean_variance()
515  * @stats: An #igt_stats_t instance
517  * Retrieves the mean of the @stats dataset.
519 double igt_stats_get_mean(igt_stats_t *stats)  in igt_stats_get_mean()  argument
521 	igt_stats_knuth_mean_variance(stats);  in igt_stats_get_mean()
523 	return stats->mean;  in igt_stats_get_mean()
528  * @stats: An #igt_stats_t instance
530  * Retrieves the variance of the @stats dataset.
532 double igt_stats_get_variance(igt_stats_t *stats)  in igt_stats_get_variance()  argument
534 	igt_stats_knuth_mean_variance(stats);  in igt_stats_get_variance()
536 	return stats->variance;  in igt_stats_get_variance()
541  * @stats: An #igt_stats_t instance
543  * Retrieves the standard deviation of the @stats dataset.
545 double igt_stats_get_std_deviation(igt_stats_t *stats)  in igt_stats_get_std_deviation()  argument
547 	igt_stats_knuth_mean_variance(stats);  in igt_stats_get_std_deviation()
549 	return sqrt(stats->variance);  in igt_stats_get_std_deviation()
554  * @stats: An #igt_stats_t instance
558  * of the @stats dataset.
566 double igt_stats_get_iqm(igt_stats_t *stats)  in igt_stats_get_iqm()  argument
571 	igt_stats_ensure_sorted_values(stats);  in igt_stats_get_iqm()
573 	q1 = (stats->n_values + 3) / 4;  in igt_stats_get_iqm()
574 	q3 = 3 * stats->n_values / 4;  in igt_stats_get_iqm()
578 		mean += (sorted_value(stats, q1 + i) - mean) / (i + 1);  in igt_stats_get_iqm()
580 	if (stats->n_values % 4) {  in igt_stats_get_iqm()
581 		double rem = .5 * (stats->n_values % 4) / 4;  in igt_stats_get_iqm()
583 		q1 = (stats->n_values) / 4;  in igt_stats_get_iqm()
584 		q3 = (3 * stats->n_values + 3) / 4;  in igt_stats_get_iqm()
586 		mean += rem * (sorted_value(stats, q1) - mean) / i++;  in igt_stats_get_iqm()
587 		mean += rem * (sorted_value(stats, q3) - mean) / i++;  in igt_stats_get_iqm()
595  * @stats: An #igt_stats_t instance
597  * Retrieves the [trimean](https://en.wikipedia.org/wiki/Trimean) of the @stats
603 double igt_stats_get_trimean(igt_stats_t *stats)  in igt_stats_get_trimean()  argument
606 	igt_stats_get_quartiles(stats, &q1, &q2, &q3);  in igt_stats_get_trimean()