Files
NeuralNetworkLib/include/NeuralNetwork/Neuron.h

324 lines
7.9 KiB
C++

#pragma once
#include <string>
#include <vector>
#include <sstream>
#include <limits>
#include <NeuralNetwork/ActivationFunction/Sigmoid.h>
#include <NeuralNetwork/BasisFunction/Linear.h>
namespace NeuralNetwork
{
/**
* @author Tomas Cernik (Tom.Cernik@gmail.com)
* @brief Abstract class of neuron. All Neuron classes should derive from this on
*/
class NeuronInterface
{
public:
/**
* @brief returns unique id for neuron
*/
virtual unsigned long id() const =0;
/**
* @brief virtual destructor for Neuron
*/
virtual ~NeuronInterface() {};
/**
* @brief This is a virtual function for storing network
* @returns json describing network and it's state
*/
virtual std::string stringify(const std::string &prefix="") const =0;
/**
* @brief Gets weight
* @param n is neuron
*/
virtual float getWeight(const NeuronInterface &n) const =0;
/**
* @brief Sets weight
* @param n is neuron
* @param w is new weight for input neuron n
*/
virtual void setWeight(const NeuronInterface& n ,const float &w) =0;
/**
* @brief Returns output of neuron
*/
virtual float output() const =0;
/**
* @brief Returns input of neuron
*/
virtual float value() const=0;
/**
* @brief Returns value for derivation of activation function
*/
// virtual float derivatedOutput() const=0;
/**
* @brief Function sets bias for neuron
* @param bias is new bias (initial value for neuron)
*/
virtual void setBias(const float &bias)=0;
/**
* @brief Function returns bias for neuron
*/
virtual float getBias() const=0;
virtual float operator()(const std::vector<float>& inputs) =0;
virtual void setInputSize(const std::size_t &size) = 0;
/**
* @brief Function returns clone of object
*/
virtual NeuronInterface* clone() const = 0;
/*
* @brief getter for basis function of neuron
*/
virtual BasisFunction::BasisFunction& getBasisFunction() =0;
/*
* @brief getter for activation function of neuron
*/
virtual ActivationFunction::ActivationFunction& getActivationFunction() =0;
};
/**
* @author Tomas Cernik (Tom.Cernik@gmail.com)
* @brief Class of FeedForward neuron.
*/
class Neuron: public NeuronInterface
{
public:
Neuron(unsigned long _id=0, const ActivationFunction::ActivationFunction &activationFunction=ActivationFunction::Sigmoid(-4.9)):
NeuronInterface(), basis(new BasisFunction::Linear),
activation(activationFunction.clone()),
id_(_id),weights(_id+1),_output(0),_value(0) {
}
Neuron(const Neuron &r): NeuronInterface(), basis(r.basis->clone()), activation(r.activation->clone()),id_(r.id_),
weights(r.weights), _output(r._output), _value(r._value) {
}
virtual ~Neuron() {
delete basis;
delete activation;
};
virtual std::string stringify(const std::string &prefix="") const override;
Neuron& operator=(const Neuron&r) {
id_=r.id_;
weights=r.weights;
basis=r.basis->clone();
activation=r.activation->clone();
return *this;
}
virtual long unsigned int id() const override {
return id_;
};
/**
* @brief Gets weight
* @param n is neuron
*/
virtual float getWeight(const NeuronInterface &n) const override {
return weights[n.id()];
}
/**
* @brief Sets weight
* @param n is neuron
* @param w is new weight for input neuron n
*/
virtual void setWeight(const NeuronInterface& n ,const float &w) override {
if(weights.size()<n.id()+1) {
weights.resize(n.id()+1);
}
weights[n.id()]=w;
}
virtual void setInputSize(const std::size_t &size) override {
if(weights.size()<size+1) {
weights.resize(size+1);
}
}
/**
* @brief Returns output of neuron
*/
virtual float output() const override {
return _output;
}
/**
* @brief Returns input of neuron
*/
virtual float value() const override {
return _value;
}
/**
* @brief Function sets bias for neuron
* @param _bias is new bias (initial value for neuron)
*/
virtual void setBias(const float &_bias) override {
weights[0]=_bias;
}
/**
* @brief Function returns bias for neuron
*/
virtual float getBias() const override {
return weights[0];
}
float operator()(const std::vector<float>& inputs) {
//compute value
_value=basis->operator()(weights,inputs);
//compute output
_output=activation->operator()(_value);
return _output;
}
virtual Neuron* clone() const override {
Neuron *n = new Neuron;
*n=*this;
return n;
}
virtual BasisFunction::BasisFunction& getBasisFunction() override {
return *basis;
}
virtual ActivationFunction::ActivationFunction& getActivationFunction() override {
return *activation;
}
protected:
BasisFunction::BasisFunction *basis;
ActivationFunction::ActivationFunction *activation;
unsigned long id_;
std::vector<float> weights;
float _output;
float _value;
};
class BiasNeuron: public NeuronInterface {
public:
class usageException : public std::exception {
public:
usageException(const std::string &text_):text(text_) {
}
virtual const char* what() const noexcept override {
return text.c_str();
}
protected:
std::string text;
};
virtual float getBias() const override { return 0; };
virtual float getWeight(const NeuronInterface&) const override { return 0; }
virtual void setBias(const float&) override{ }
virtual float output() const override { return 1.0; };
virtual void setWeight(const NeuronInterface&, const float&) override { }
virtual std::string stringify(const std::string& prefix = "") const override { return prefix+"{ \"class\" : \"NeuralNetwork::BiasNeuron\" }"; }
virtual float value() const override { return 1.0; }
virtual long unsigned int id() const override { return 0; }
virtual float operator()(const std::vector< float >&) override { return 1.0; }
virtual void setInputSize(const std::size_t&) override {
}
virtual BiasNeuron* clone() const { return new BiasNeuron(); }
virtual BasisFunction::BasisFunction& getBasisFunction() override {
throw usageException("basis function");
}
virtual ActivationFunction::ActivationFunction& getActivationFunction() override {
throw usageException("activation function");
}
};
class InputNeuron: public NeuronInterface {
public:
class usageException : public std::exception {
public:
usageException(const std::string &text_):text(text_) {
}
virtual const char* what() const noexcept override {
return text.c_str();
}
protected:
std::string text;
};
InputNeuron(long unsigned int _id): id_(_id) {
}
virtual float getBias() const override { return 0; };
virtual float getWeight(const NeuronInterface&) const override { return 0; }
virtual void setBias(const float&) override{ }
virtual float output() const override { return 1.0; };
virtual void setWeight(const NeuronInterface&, const float&) override { }
virtual std::string stringify(const std::string& prefix = "") const override { return prefix+"{ \"class\" : \"NeuralNetwork::InputNeuron\", \"id\": "+std::to_string(id_)+" }"; }
virtual float value() const override { return 1.0; }
virtual long unsigned int id() const override { return id_; }
virtual float operator()(const std::vector< float >&) override { return 1.0; }
virtual void setInputSize(const std::size_t&) override {
}
virtual InputNeuron* clone() const { return new InputNeuron(id_); }
virtual BasisFunction::BasisFunction& getBasisFunction() override {
throw usageException("basis function");
}
virtual ActivationFunction::ActivationFunction& getActivationFunction() override {
throw usageException("activation function");
}
protected:
long unsigned int id_;
};
}