LookingGlass/common/src/runningavg.c
2024-02-01 17:16:31 +11:00

78 lines
1.7 KiB
C

/**
* Looking Glass
* Copyright © 2017-2024 The Looking Glass Authors
* https://looking-glass.io
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc., 59
* Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "common/runningavg.h"
#include "common/debug.h"
#include <stdlib.h>
struct RunningAvg
{
int length, samples;
int pos;
int64_t value;
int64_t values[0];
};
RunningAvg runningavg_new(int length)
{
struct RunningAvg * ra = calloc(1, sizeof(*ra) + sizeof(*ra->values) * length);
if (!ra)
{
DEBUG_ERROR("out of memory");
return NULL;
}
ra->length = length;
return ra;
}
void runningavg_free(RunningAvg * ra)
{
free(*ra);
*ra = NULL;
}
void runningavg_push(RunningAvg ra, int64_t value)
{
if (ra->samples == ra->length)
ra->value -= ra->values[ra->pos];
else
++ra->samples;
ra->value += value;
ra->values[ra->pos++] = value;
if (ra->pos == ra->length)
ra->pos = 0;
}
void runningavg_reset(RunningAvg ra)
{
ra->samples = 0;
ra->pos = 0;
ra->value = 0;
}
double runningavg_calc(RunningAvg ra)
{
return (double)ra->value / ra->samples;
}