68 lines
1.7 KiB
C++
68 lines
1.7 KiB
C++
// Arduino Moving Average Library
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// https://github.com/JChristensen/movingAvg
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// Copyright (C) 2018 by Jack Christensen and licensed under
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// GNU GPL v3.0, https://www.gnu.org/licenses/gpl.html
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#include <movingAvg.h>
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// initialize - allocate the interval array
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void movingAvg::begin()
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{
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m_readings = new int[m_interval];
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}
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// add a new reading and return the new moving average
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int movingAvg::reading(int newReading)
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{
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// add each new data point to the sum until the m_readings array is filled
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if (m_nbrReadings < m_interval) {
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++m_nbrReadings;
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m_sum += newReading;
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}
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// once the array is filled, subtract the oldest data point and add the new one
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else {
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m_sum = m_sum - m_readings[m_next] + newReading;
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}
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m_readings[m_next] = newReading;
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if (++m_next >= m_interval) m_next = 0;
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return (m_sum + m_nbrReadings / 2) / m_nbrReadings;
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}
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// just return the current moving average
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int movingAvg::getAvg()
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{
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return (m_sum + m_nbrReadings / 2) / m_nbrReadings;
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}
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// return the average for a subset of the data, the most recent nPoints readings.
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// for invalid values of nPoints, return zero.
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int movingAvg::getAvg(int nPoints)
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{
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if (nPoints < 1 || nPoints > m_interval || nPoints > m_nbrReadings) {
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return 0;
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}
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else {
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long sum{0};
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int i = m_next;
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for (int n=0; n<nPoints; ++n) {
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if (i == 0) {
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i = m_interval - 1;
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}
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else {
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--i;
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}
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sum += m_readings[i];
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}
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return (sum + nPoints / 2) / nPoints;
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}
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}
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// start the moving average over again
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void movingAvg::reset()
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{
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m_nbrReadings = 0;
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m_sum = 0;
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m_next = 0;
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}
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