boinc/lib/average.cpp

77 lines
2.0 KiB
C++

// This file is part of BOINC.
// http://boinc.berkeley.edu
// Copyright (C) 2010 University of California
//
// BOINC is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License
// as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// BOINC 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with BOINC. If not, see <http://www.gnu.org/licenses/>.
#include "average.h"
bool AVERAGE::update(double sample) {
double delta, limit;
bool truncated = false;
if (sample < 0) return true;
if (n) {
if (sample > avg*sample_limit) {
sample = avg*sample_limit;
truncated = true;
}
}
n++;
if (n < n_threshold) {
avg += (sample-avg)/n;
} else {
delta = sample - avg;
avg += sample_weight*delta;
}
return truncated;
}
bool AVERAGE_VAR::update_var(double sample) {
double delta, limit;
bool truncated = false;
if (sample < 0) return true;
if (n) {
if (sample > avg*sample_limit) {
sample = avg*sample_limit;
truncated = true;
}
}
n++;
if (n < n_threshold) {
q += (sample - avg ) * (n - 1) / n;
avg += (sample-avg)/n;
var = q/n;
} else {
delta = sample - avg;
avg += sample_weight*delta;
double vdelta = (delta*delta - var);
var += sample_weight*vdelta;
}
return truncated;
}
#if 0
#include <stdio.h>
#include "util.h"
int main() {
AVERAGE_VAR avg;
avg.init(100, .01, 10);
for (int i=0; i<1000; i++) {
avg.update_var(drand());
printf("%d %f %f\n", i, avg.get_avg(), sqrt(avg.get_var()));
}
}
#endif