sdrangel/sdrbase/util/movingaverage.h

136 wiersze
4.2 KiB
C++

///////////////////////////////////////////////////////////////////////////////////////
// //
// http://stackoverflow.com/questions/10990618/calculate-rolling-moving-average-in-c //
// //
// Copyright (C) 2016 Edouard Griffiths, F4EXB //
// //
// 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 as version 3 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 V3 for more details. //
// //
// You should have received a copy of the GNU General Public License //
// along with this program. If not, see <http://www.gnu.org/licenses/>. //
///////////////////////////////////////////////////////////////////////////////////////
#ifndef _UTIL_MOVINGAVERAGE_H_
#define _UTIL_MOVINGAVERAGE_H_
#include <algorithm>
template <typename T, typename Total, int N>
class MovingAverageUtil
{
public:
MovingAverageUtil()
: m_num_samples(0), m_index(0), m_total(0)
{ }
void reset()
{
m_num_samples = 0;
m_index = 0;
m_total = 0;
}
void operator()(T sample)
{
if (m_num_samples < N) // fill up
{
m_samples[m_num_samples++] = sample;
m_total += sample;
}
else // roll
{
T& oldest = m_samples[m_index];
m_total += sample - oldest;
oldest = sample;
m_index = (m_index + 1) % N;
}
}
double asDouble() const { return ((double)m_total) / N; }
float asFloat() const { return ((float)m_total) / N; }
operator T() const { return m_total / N; }
T instantAverage() const { return m_total / (m_num_samples == 0 ? 1 : m_num_samples); }
private:
T m_samples[N];
int m_num_samples;
unsigned int m_index;
Total m_total;
};
template <typename T, typename Total>
class MovingAverageUtilVar
{
public:
MovingAverageUtilVar(unsigned int size)
: m_num_samples(0), m_index(0), m_total(0)
{
m_samples.resize(size);
m_samplesSizeInvF = 1.0f / size;
m_samplesSizeInvD = 1.0 / size;
}
void reset()
{
m_num_samples = 0;
m_index = 0;
m_total = 0;
}
void resize(unsigned int size)
{
reset();
m_samples.resize(size);
m_samplesSizeInvF = 1.0f / size;
m_samplesSizeInvD = 1.0 / size;
}
unsigned int size() const
{
return m_samples.size();
}
void operator()(T sample)
{
if (m_num_samples < m_samples.size()) // fill up
{
m_samples[m_num_samples++] = sample;
m_total += sample;
}
else // roll
{
T& oldest = m_samples[m_index];
m_total += sample - oldest;
oldest = sample;
m_index++;
if (m_index == m_samples.size())
m_index = 0;
}
}
double asDouble() const { return m_total * m_samplesSizeInvD; }
float asFloat() const { return m_total * m_samplesSizeInvF; }
operator T() const { return m_total / m_samples.size(); }
T instantAverage() const { return m_total / (m_num_samples == 0 ? 1 : m_num_samples); }
private:
std::vector<T> m_samples;
unsigned int m_num_samples;
unsigned int m_index;
Total m_total;
float m_samplesSizeInvF;
double m_samplesSizeInvD;
};
#endif /* _UTIL_MOVINGAVERAGE_H_ */