MinMaxScaler.h

/*
 * MinMaxScaler.h
 *
 * (c) 2015 Sofian Audry        :: info(@)sofianaudry(.)com
 * (c) 2015 Thomas O Fredericks :: tof(@)t-o-f(.)info
 *
 * 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 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 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 MIN_MAX_SCALER_H_
#define MIN_MAX_SCALER_H_
 
#include "PqCore.h"
#include "MovingFilter.h"
 
namespace pq {
 
class MinMaxScaler : public MovingFilter {
public:
  MinMaxScaler(Engine& engine = Engine::primary());
 
  MinMaxScaler(float timeWindow, Engine& engine = Engine::primary());
 
  virtual ~MinMaxScaler() {}
 
  float minValue() const { return _minValue; }
 
  float maxValue() const { return _maxValue; }
 
  virtual void infiniteTimeWindow();
 
  virtual void timeWindow(float seconds);
 
  virtual float timeWindow() const;
 
  virtual bool timeWindowIsInfinite() const;
 
  virtual void reset();
 
  virtual float put(float value);
 
protected:
  virtual void step();
 
  // Time window (in seconds).
  float _timeWindow;
 
  // Minimum value ever put (decays over time if time window is finite).
  float _minValue;
 
  // Maximum value ever put (decays over time if time window is finite).
  float _maxValue;
 
  // Smoothed minimum value.
  float _smoothedMinValue;
 
  // Smoothed minimum value.
  float _smoothedMaxValue;
 
  // Number of samples that have been processed thus far.
  unsigned int _nSamples;
  
  // Variables used to compute current value average during a step (in case of multiple calls to put()).
  float _currentValueStep;
};
 
}
 
#endif