cppbasedann/myclasses.cpp
2022-01-15 21:36:05 +01:00

363 lines
12 KiB
C++

#include <iostream>
#include <ctime>
#include <cmath>
#include <forward_list>
#include "myclasses.h"
using namespace std;
Neuron::Neuron(int prev_layer_size)
{
for(int i(1) ; i<=prev_layer_size ; i++)
{
//weights.push_front(Tools::get_random(0.0, 1.0));
weights.push_front(1.0);
}
bias = 0.1;
weighted_sum = 0.0;
activated_output = 0.0;
derror = 0.0;
}
void Neuron::set_activated_output(float value)
{
activated_output = value;
}
float Neuron::get_weighted_sum()
{
return weighted_sum;
}
float Neuron::get_activated_output()
{
return activated_output;
}
void Neuron::set_derror(float value)
{
derror = value;
}
float Neuron::get_derror()
{
return derror;
}
void Neuron::set_nth_weight(int n, float value)
{
int i=1;
forward_list<float>::iterator current_weight(weights.begin());
while(i<n)
{
current_weight++;
i++;
}
*current_weight = value;
}
float Neuron::get_nth_weight(int n)
{
int i=1;
forward_list<float>::iterator current_weight(weights.begin());
while(i<n)
{
current_weight++;
i++;
}
return *current_weight;
}
void Neuron::activate(forward_list<Neuron>::iterator &prev_layer_it, Activ activ_function)
{
weighted_sum = bias;
for(forward_list<float>::iterator it(weights.begin()) ; it!=weights.end() ; ++it)
{
weighted_sum += (*it) * (prev_layer_it->activated_output);
prev_layer_it++;
}
activated_output = Tools::activation_function(activ_function, weighted_sum);
}
Network::Network(int n_layers, int n_neurons)
{
for(int i(1) ; i<=n_layers ; i++)
{
forward_list<Neuron> current_layer;
for(int j(1) ; j<=n_neurons ; j++)
{
if(i==1)
{
current_layer.push_front( Neuron(0) );
}else if(i==n_layers)
{
current_layer.push_front( Neuron(n_neurons) );
}else
{
current_layer.push_front( Neuron(n_neurons) );
}
}
layers.push_back(current_layer);
}
h_activ = RELU;
//o_activ = SIGMOID;
o_activ = LINEAR;
}
Network::Network(const std::vector<int> &n_neurons, Activ h_activ, Activ o_activ)
{
for(int i(0) ; i<n_neurons.size() ; i++)
{
forward_list<Neuron> current_layer;
for(int j(1) ; j<=n_neurons[i] ; j++)
{
if(i==0)
{
current_layer.push_front( Neuron(0) );
}else if(i==n_neurons.size()-1)
{
current_layer.push_front( Neuron(n_neurons[i-1]) );
}else
{
current_layer.push_front( Neuron(n_neurons[i-1]) );
}
}
layers.push_back(current_layer);
}
h_activ = h_activ;
o_activ = o_activ;
}
bool Network::forward(const std::vector<float> &input, const std::vector<float> &target)
{
int layer_counter = 0;
for(list<forward_list<Neuron>>::iterator current_layer(layers.begin()) ; current_layer!=layers.end() ; ++current_layer)
{//inside current layer
layer_counter++;
if(layer_counter==1)
{
int i=0;
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
current_neuron->set_activated_output( input.at(i) );
i++;
}
}else if(layer_counter==layers.size())
{
list<forward_list<Neuron>>::iterator temp = current_layer;
temp--; //previous layer
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
forward_list<Neuron>::iterator prev_layer_it(temp->begin());
current_neuron->activate(prev_layer_it, o_activ);
}
}else
{
list<forward_list<Neuron>>::iterator temp_prev_layer = current_layer; //temp_prev_layer set at current layer
temp_prev_layer--; ////temp_prev_layer set now at previous layer
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
forward_list<Neuron>::iterator prev_layer_it(temp_prev_layer->begin());
current_neuron->activate(prev_layer_it, h_activ);
}
}
}
set_errors(target);
return true;
}
bool Network::set_errors(const std::vector<float> &target)
{
int layer_counter = layers.size()+1;
for(list<forward_list<Neuron>>::reverse_iterator current_layer(layers.rbegin()) ; current_layer!=layers.rend() ; ++current_layer)
{//inside current layer
layer_counter--;
if(layer_counter==layers.size())
{
int i=0;
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
current_neuron->set_derror( (current_neuron->get_activated_output()-target.at(i))*Tools::activation_function_derivative(o_activ,current_neuron->get_weighted_sum()) );
i++;
}
}else if(layer_counter>1) //all hidden layers
{
list<forward_list<Neuron>>::reverse_iterator temp_next_layer = current_layer; //temp_next_layer set at current layer
temp_next_layer--; //temp_next_layer set now at next layer
int neuron_counter=0;
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
neuron_counter++;
current_neuron->set_derror(0.0);
for(forward_list<Neuron>::iterator next_layer_current_neuron(temp_next_layer->begin()) ; next_layer_current_neuron!=temp_next_layer->end() ; ++next_layer_current_neuron)
{
current_neuron->set_derror( current_neuron->get_derror()+next_layer_current_neuron->get_derror()*next_layer_current_neuron->get_nth_weight(neuron_counter) );
}
current_neuron->set_derror( current_neuron->get_derror()*Tools::activation_function_derivative(h_activ,current_neuron->get_weighted_sum()) );
}
}
}
return true;
}
bool Network::backward(float learning_rate)
{
int layer_counter = layers.size()+1;
for(list<forward_list<Neuron>>::reverse_iterator current_layer(layers.rbegin()) ; current_layer!=layers.rend() ; ++current_layer)
{//inside current layer
layer_counter--;
if(layer_counter>1) //all layers except input layer
{
list<forward_list<Neuron>>::reverse_iterator temp_prev_layer = current_layer; //temp_prev_layer set at current layer
temp_prev_layer++; //temp_prev_layer set now at previous layer
int neuron_counter=0;
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
neuron_counter++;
for(forward_list<Neuron>::iterator prev_layer_current_neuron(temp_prev_layer->begin()) ; prev_layer_current_neuron!=temp_prev_layer->end() ; ++prev_layer_current_neuron)
{
//current_neuron->set_nth_weight()
current_neuron->set_derror( current_neuron->get_derror()+prev_layer_current_neuron->get_derror()*prev_layer_current_neuron->get_nth_weight(neuron_counter) );
}
}
}
}
return true;
}
float Network::predict(const std::vector<float> &input)
{
return 0.0;
}
void Network::print()
{
cout << endl << "#>>==========================================<<#" << endl;
cout << "# NEURAL NETWORK #" << endl;
cout << "#>>==========================================<<#" << endl;
cout << ">> Number of layers : " << layers.size() << endl;
cout << "------------------------------------------------" << endl;
int layer_counter = 0;
int prev_layer_size_temp = 0, params_counter = 0;
for(list<forward_list<Neuron>>::iterator it1(layers.begin()) ; it1!=layers.end() ; ++it1)
{
layer_counter++;
int current_layer_size = 0;
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2)
{
current_layer_size++;
}
if(layer_counter==1)
{
prev_layer_size_temp = current_layer_size;
}
else
{
params_counter += (prev_layer_size_temp+1)*current_layer_size;
prev_layer_size_temp = current_layer_size;
}
if(layer_counter==1)
{
cout << ">> Input layer" << endl;
cout << "size : " << current_layer_size << endl;
cout << "neurons' activations : ";
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){cout << it2->get_activated_output() << " ";}
cout << endl;
}else if(layer_counter==layers.size())
{
cout << (">> Output layer\n");
cout << "size : " << current_layer_size << endl;
cout << ("neurons' activations : ");
//for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){cout << it2->get_activated_output() << " ";}
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){cout << it2->get_activated_output() << " " << it2->get_derror() << endl; for(int i=1;i<=3;i++){cout << it2->get_nth_weight(i) << " ";}cout<<endl;}//to be deleted
cout << endl;
}else
{
cout << ">> Hidden layer " << layer_counter-1 << endl;
cout << "size : " << current_layer_size << endl;
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){cout << it2->get_activated_output() << " " << it2->get_derror() << endl;}//to be deleted
}
cout << "------------------------------------------------" << endl;
}
cout << "Number of parameters : ";
cout << params_counter << endl;
cout << "#>>==========================================<<#" << endl << endl;
}
void Tools::activate_randomness()
{
srand(time(NULL));
}
float Tools::get_random(float mini, float maxi)
{
return mini + ((float)rand()/(float)RAND_MAX) * (maxi-mini);
}
float Tools::activation_function(Activ activ, float value)
{
Tools t;
switch(activ)
{
case RELU:
return t.relu(value);
case SIGMOID:
return t.sigmoid(value);
case TANH:
return tanh(value);
case LINEAR:
return value;
default:
exit(-1);
}
}
float Tools::activation_function_derivative(Activ activ, float value)
{
Tools t;
switch(activ)
{
case RELU:
return t.relu_derivative(value);
case SIGMOID:
return t.sigmoid_derivative(value);
case TANH:
return t.tanh_derivative(value);
case LINEAR:
return 1.0;
default:
exit(-1);
}
}
float Tools::relu(float value)
{
return (value > 0.0) ? value : 0.0;
}
float Tools::sigmoid(float value)
{
return 1.0 / (1.0 + exp(-value));
}
float Tools::relu_derivative(float value)
{
return (value > 0.0) ? 1.0 : 0.0;
}
float Tools::sigmoid_derivative(float value)
{
return sigmoid(value) * (1.0 - sigmoid(value));
}
float Tools::tanh_derivative(float value)
{
return 1.0 - (tanh(value) * tanh(value));
}