Updating neuron and network classes functions

This commit is contained in:
chabisik 2022-01-15 01:30:58 +01:00
parent 639694d05c
commit f7193b3e33
3 changed files with 229 additions and 54 deletions

View file

@ -5,6 +5,7 @@
#include <vector>
#include <iterator>
using namespace std;
@ -14,20 +15,28 @@ int main(int argc, char *argv[])
cout << "Bonjour et bienvenu" << endl;
/*Neuron n0(3,SIGMOID);
Neuron n1(3,RELU);n1.set_output(1.0);
Neuron n2(3,RELU);n2.set_output(2.0);
Neuron n3(3,RELU);n3.set_output(-3.0);
forward_list<Neuron> fl;
fl.push_front(n1);fl.push_front(n2);fl.push_front(n3);
forward_list<Neuron>::iterator it(fl.begin());
n0.activate(it);
cout << "is = " << n0.get_output() << endl;*/
Network network(4, 5);
Network network(2, 5);
network.forward({1.0,1.0,1.0,1.0,1.0}, {1.0,1.0,1.0,1.0,1.0});
network.print();
/*Neuron n(3), n1(1), n2(1), n3(1);
forward_list<Neuron> fl;
fl.push_front(n1);
fl.push_front(n2);
fl.push_front(n3);
forward_list<Neuron>::iterator it(fl.begin());
n.activate(it, LINEAR);
cout << "weighted sum = " << n.get_weighted_sum() << endl;*/
/*list<float> l;
l.push_back(1.0);
l.push_back(2.0);
l.push_back(3.0);
for(list<float>::reverse_iterator it(l.rbegin()) ; it!=l.rend() ; ++it)
{
cout << *it << endl;
}*/
return 0;
}

View file

@ -10,51 +10,51 @@ 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(Tools::get_random(0.0, 1.0));
weights.push_front(1.0);
}
bias = 0.1;
output = 0.0;
weighted_sum = 0.0;
activated_output = 0.0;
derror = 0.0;
}
void Neuron::set_output(float value)
void Neuron::set_activated_output(float value)
{
output = 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::activate(forward_list<Neuron>::iterator &prev_layer_it, Activ activ_function)
{
output = bias;
weighted_sum = bias;
for(forward_list<float>::iterator it(weights.begin()) ; it!=weights.end() ; ++it)
{
output += (*it) * ((*prev_layer_it).output);
weighted_sum += (*it) * (prev_layer_it->activated_output);
prev_layer_it++;
}
switch(activ_function)
{
case RELU:
output = (output > 0.0) ? output : 0.0;
break;
case SIGMOID:
output = 1.0 / (1.0 + exp(-output));
break;
case TANH:
output = tanh(output);
break;
default:
//LINEAR (output=direct weighted sum) as base behavior
break;
}
activated_output = Tools::activation_function(activ_function, weighted_sum);
}
float Neuron::get_output()//to be deleted later
{
return output;
}
Network::Network(int n_layers, int n_neurons)
{
@ -77,7 +77,8 @@ Network::Network(int n_layers, int n_neurons)
layers.push_back(current_layer);
}
h_activ = RELU;
o_activ = SIGMOID;
//o_activ = SIGMOID;
o_activ = LINEAR;
}
Network::Network(const std::vector<int> &n_neurons, Activ h_activ, Activ o_activ)
@ -104,6 +105,84 @@ Network::Network(const std::vector<int> &n_neurons, Activ h_activ, Activ o_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);
}
}
}
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
for(forward_list<Neuron>::iterator current_neuron(current_layer->begin()) ; current_neuron!=current_layer->end() ; ++current_neuron)
{//inside current neuron
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)
{
//
}
}
}
}
return true;
}
bool Network::backward(float learning_rate)
{
return true;
}
float Network::predict(const std::vector<float> &input)
{
return 0.0;
}
void Network::print()
{
cout << endl << "#>>==========================================<<#" << endl;
@ -134,15 +213,15 @@ void Network::print()
{
cout << ">> Input layer" << endl;
cout << "size : " << current_layer_size << endl;
cout << "neurons' outputs : ";
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){it2->get_output();}
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' outputs : ");
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){it2->get_output();}
cout << ("neurons' activations : ");
for(forward_list<Neuron>::iterator it2(it1->begin()) ; it2!=it1->end() ; ++it2){cout << it2->get_activated_output() << " ";}
cout << endl;
}else
{
@ -164,4 +243,71 @@ void Tools::activate_randomness()
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));
}

View file

@ -15,13 +15,18 @@ class Neuron
{
public:
Neuron(int prev_layer_size); //prev_layer_size = number of weights
void set_output(float value);
float get_output();//to be deleted
//void set_weighted_sum(float weighted_sum);
float get_weighted_sum();
void set_activated_output(float value);
float get_activated_output();
void set_derror(float value);
float get_derror();
void activate(std::forward_list<Neuron>::iterator &prev_layer_it, Activ activ_function=LINEAR);
private:
std::forward_list<float> weights;
float bias;
float output;
float weighted_sum;
float activated_output;
float derror;
};
@ -31,15 +36,21 @@ class Network
public:
Network(int n_layers, int n_neurons);
Network(const std::vector<int> &n_neurons, Activ h_activ=RELU, Activ o_activ=SIGMOID);
float predict(const std::vector<float> &input);
void print();
//to be deleted
bool forward(const std::vector<float> &input, const std::vector<float> &target);
bool backward();
bool set_errors(const std::vector<float> &target);
private:
std::list<std::forward_list<Neuron>> layers;
Activ h_activ;
Activ o_activ;
bool _set_errors();
//bool forward(const std::vector<float> &input, const std::vector<float> &target);
//bool set_errors(const std::vector<float> &target);
bool backward(float learning_rate);
};
@ -48,8 +59,17 @@ class Tools
public:
static void activate_randomness();
static float get_random(float mini, float maxi);
//Activation functions and their derivatives
static float activation_function(Activ activ, float value);
static float activation_function_derivative(Activ activ, float value);
//float activation_function(Activ activ, float value);
//float activation_function_derivative(Activ activ, float value);
private:
float relu(float value);
float sigmoid(float value);
float relu_derivative(float value);
float sigmoid_derivative(float value);
float tanh_derivative(float value);
};
#endif