MomentumUpdater.hpp

/*
 * MomentumUpdater.hpp
 *
 *  Created on: Feburary 27, 2014
 *      Author: slundquist
 */

#ifndef MOMENTUMUPDATER_HPP_
#define MOMENTUMUPDATER_HPP_

#include "weightupdaters/HebbianUpdater.hpp"

namespace PV {

class MomentumUpdater : public HebbianUpdater {
  protected:
   virtual void ioParam_momentumMethod(enum ParamsIOFlag ioFlag);

   virtual void ioParam_timeConstantTau(enum ParamsIOFlag ioFlag);

   virtual void ioParam_momentumTau(enum ParamsIOFlag ioFlag);

   virtual void ioParam_momentumDecay(enum ParamsIOFlag ioFlag);
 // end of MomentumUpdater parameters

  public:
   // default values for timeConstantTau
   static constexpr float mDefaultTimeConstantTauSimple    = 0.25f;
   static constexpr float mDefaultTimeConstantTauViscosity = 100.0f;
   static constexpr float mDefaultTimeConstantTauAlex      = 0.9f;

   MomentumUpdater(char const *name, HyPerCol *hc);

   virtual ~MomentumUpdater() {}

   char const *getMomentumMethod() { return mMomentumMethod; }
   float getTimeConstantTau() const { return mTimeConstantTau; }
   bool isUsingDeprecatedMomentumTau() const { return mUsingDeprecatedMomentumTau; }

  protected:
   MomentumUpdater() {}

   int initialize(char const *name, HyPerCol *hc);

   virtual void setObjectType() override;

   virtual int ioParamsFillGroup(enum ParamsIOFlag ioFlag) override;

   void checkTimeConstantTau();

   virtual Response::Status allocateDataStructures() override;

   virtual Response::Status registerData(Checkpointer *checkpointer) override;

   virtual Response::Status readStateFromCheckpoint(Checkpointer *checkpointer) override;

   virtual int updateWeights(int arborId) override;

   void applyMomentum(int arborId);

   void applyMomentum(int arborId, float dwFactor, float wFactor);

   void applyMomentumDeprecated(int arborId);

   void applyMomentumDeprecated(int arborId, float dwFactor, float wFactor);

  protected:
   enum Method { UNDEFINED_METHOD, VISCOSITY, SIMPLE, ALEX };

   char *mMomentumMethod  = nullptr;
   Method mMethod         = UNDEFINED_METHOD;
   float mMomentumTau     = 0.25f; // Deprecated in favor of mTimeConstantTau Nov 19, 2018.
   float mTimeConstantTau = mDefaultTimeConstantTauViscosity;
   float mMomentumDecay   = 0.0f;

   Weights *mPrevDeltaWeights       = nullptr;
   bool mUsingDeprecatedMomentumTau = false;
};

} // namespace PV

#endif // MOMENTUMUPDATER_HPP_