#if 0
This adds a generic exponentially weighted moving average function. This
implementation makes use of a structure which keeps a scaled up internal
representation to reduce rounding errors.

The idea for this implementation comes from the rt2x00 driver (rt2x00link.c)
and i would like to use it in several places in the mac80211 and ath5k code.
#endif

#ifndef _LINUX_AVERAGE_H
#define _LINUX_AVERAGE_H

#define AVG_FACTOR	1000

struct avg_val {
	int value;
	int internal;
};

/**
 * moving_average -  Exponentially weighted moving average
 * @avg: average structure
 * @val: current value
 * @samples: number of samples
 *
 * This implementation make use of a struct avg_val to prevent rounding
 * errors.
 */
static inline struct avg_val
moving_average(const struct avg_val avg, const int val, const int samples)
{
	struct avg_val ret;
	ret.internal = avg.internal  ?
		(((avg.internal * (samples - 1)) +
			(val * AVG_FACTOR)) / samples) :
		(val * AVG_FACTOR);
	ret.value = ret.internal / AVG_FACTOR;
	return ret;
}

#endif /* _LINUX_AVERAGE_H */


#include <stdio.h>

int main(int argc, char *argv[])
{
	struct avg_val	avg = {};
	int count;
	int val;
	int sum = 0;

	for (count = 1; count <= 10; count++) {
		val = count + count/2;
		sum += val;
		avg = moving_average(avg, val, count);
		printf("count: %d, val: %d, sum: %d, avg: %d, internal: %d\n",
			count, val, sum, avg.value, avg.internal);
	}

	return 0;
}