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c-net/neuronal_network.c
2023-09-22 09:18:08 +02:00

379 lines
No EOL
12 KiB
C

#include <stdlib.h>
#include "neuronal_network.h"
#include <stdio.h>
#include <time.h>
#include <math.h>
double sigmoid(double input);
double sigmoid_derivative(double x);
Matrix* softmax(Matrix* matrix);
double square(double input);
double loss_function(Matrix* output_matrix, int image_label);
void backPropagation(double learning_rate, Matrix* weights, Matrix* biases, Matrix* current_layer_activation, Matrix* previous_layer_activation, Matrix* sigma_old);
Neural_Network* new_network(int input_size, int hidden_size, int output_size, double learning_rate){
Neural_Network *network = malloc(sizeof(Neural_Network));
// initialize networks variables
network->hidden_size = hidden_size;
network->input_size = input_size;
network->output_size = output_size;
network->learning_rate = learning_rate;
network->weights_1 = matrix_create(hidden_size, input_size);
network->weights_2 = matrix_create(hidden_size, hidden_size);
network->weights_3 = matrix_create(hidden_size, hidden_size);
network->weights_output = matrix_create(output_size, hidden_size);
network->bias_1 = matrix_create(hidden_size, 1);
network->bias_2 = matrix_create(hidden_size, 1);
network->bias_3 = matrix_create(hidden_size, 1);
network->bias_output = matrix_create(output_size, 1);
return network;
}
void randomize_network(Neural_Network* network, int scope){
matrix_randomize(network->weights_1, scope);
matrix_randomize(network->weights_2, scope);
matrix_randomize(network->weights_3, scope);
matrix_randomize(network->weights_output, scope);
matrix_randomize(network->bias_1, scope);
matrix_randomize(network->bias_2, scope);
matrix_randomize(network->bias_3, scope);
matrix_randomize(network->bias_output, scope);
}
//void print_network(Neural_Network* network){};
void free_network(Neural_Network* network){
matrix_free(network->weights_1);
matrix_free(network->weights_2);
matrix_free(network->weights_3);
matrix_free(network->weights_output);
matrix_free(network->bias_1);
matrix_free(network->bias_2);
matrix_free(network->bias_3);
matrix_free(network->bias_output);
free(network);
}
void save_network(Neural_Network* network) {
char* file_name = "../networks/newest_network.txt";
// create file
FILE* save_file = fopen(file_name, "w");
// check if file is successfully opened
if(save_file == NULL) {
printf("ERROR: Something went wrong in file creation! (save_network)");
exit(1);
}
// save network size to first line of the file
fprintf(save_file, "%d\n", network->input_size);
fprintf(save_file, "%d\n", network->hidden_size);
fprintf(save_file, "%d\n", network->output_size);
// close the file
fclose(save_file);
// save first layer
matrix_save(network->bias_1, file_name);
matrix_save(network->weights_1, file_name);
// save second layer
matrix_save(network->bias_2, file_name);
matrix_save(network->weights_2, file_name);
// save third layer
matrix_save(network->bias_3, file_name);
matrix_save(network->weights_3, file_name);
// save output weights
matrix_save(network->bias_output, file_name);
matrix_save(network->weights_output, file_name);
printf("Network Saved!");
}
Neural_Network* load_network(char* file) {
// create file pointer and open file
FILE* save_file = fopen(file, "r");
// check if file could be opened
if(save_file == NULL) {
printf("ERROR: File could not be opened/found! (load_network)");
exit(1);
}
// read & store the information on the size of the network from the save file
char buffer[MAX_BYTES];
fgets(buffer, MAX_BYTES, save_file);
int input_size = (int) strtol(buffer, NULL, 10);
fgets(buffer, MAX_BYTES, save_file);
int hidden_size = (int) strtol(buffer, NULL, 10);
fgets(buffer, MAX_BYTES, save_file);
int output_size = (int) strtol(buffer, NULL, 10);
// create a new network to fill with the saved data
Neural_Network* saved_network = new_network(input_size, hidden_size, output_size, 0);
// load matrices from file into struct
saved_network->bias_1 = load_next_matrix(save_file);
saved_network->weights_1 = load_next_matrix(save_file);
saved_network->bias_2 = load_next_matrix(save_file);
saved_network->weights_2 = load_next_matrix(save_file);
saved_network->bias_3 = load_next_matrix(save_file);
saved_network->weights_3 = load_next_matrix(save_file);
saved_network->bias_output = load_next_matrix(save_file);
saved_network->weights_output = load_next_matrix(save_file);
// return saved network
fclose(save_file);
return saved_network;
}
double measure_network_accuracy(Neural_Network* network, Image** images, int amount) {
int num_correct = 0;
for (int i = 0; i < amount; i++) {
Matrix* prediction = predict_image(network, images[i]);
if (matrix_argmax(prediction) == images[i]->label) {
num_correct++;
}
matrix_free(prediction);
}
return 1.0 * num_correct / amount;
}
Matrix* predict_image(Neural_Network* network, Image* image){
Matrix* image_data = matrix_flatten(image->pixel_values, 0);
Matrix* res = predict(network, image_data);
matrix_free(image_data);
return res;
}
Matrix* predict(Neural_Network* network, Matrix* image_data) {
Matrix* h1_dot = dot(network->weights_1, image_data);
Matrix* h1_add = add(h1_dot, network->bias_1);
Matrix* h1_outputs = apply(sigmoid, h1_add);
Matrix* h2_dot = dot(network->weights_2, h1_outputs);
Matrix* h2_add = add(h2_dot, network->bias_2);
Matrix* h2_outputs = apply(sigmoid, h2_add);
Matrix* h3_dot = dot(network->weights_3, h2_outputs);
Matrix* h3_add = add(h3_dot, network->bias_3);
Matrix* h3_outputs = apply(sigmoid, h3_add);
Matrix* final_dot = dot(network->weights_output, h3_outputs);
Matrix* final_add = add(final_dot, network->bias_output);
Matrix* final_outputs = apply(sigmoid, final_add);
Matrix* result = softmax(final_outputs);
matrix_free(h1_dot);
matrix_free(h1_add);
matrix_free(h1_outputs);
matrix_free(h2_dot);
matrix_free(h2_add);
matrix_free(h2_outputs);
matrix_free(h3_dot);
matrix_free(h3_add);
matrix_free(h3_outputs);
matrix_free(final_dot);
matrix_free(final_add);
matrix_free(final_outputs);
return result;
}
double cost_function(Matrix* calculated, int expected){
calculated->numbers[expected] -= 1;
apply(square, calculated);
// double loss = 0.5 * (target - output) * (target - output);
return 0;
}
void train_network(Neural_Network* network, Image *image, int label) {
// Flatten the image into matrix
Matrix* input = matrix_flatten(image->pixel_values, 0);
// Perform forward propagation
Matrix* h1_dot = dot(network->weights_1, input);
Matrix* h1_add = add(h1_dot, network->bias_1);
Matrix* h1_outputs = apply(sigmoid, h1_add);
Matrix* h2_dot = dot(network->weights_2, h1_outputs);
Matrix* h2_add = add(h2_dot, network->bias_2);
Matrix* h2_outputs = apply(sigmoid, h2_add);
Matrix* h3_dot = dot(network->weights_3, h2_outputs);
Matrix* h3_add = add(h3_dot, network->bias_3);
Matrix* h3_outputs = apply(sigmoid, h3_add);
Matrix* final_dot = dot(network->weights_output, h3_outputs);
Matrix* final_add = add(final_dot, network->bias_output);
Matrix* final_outputs = apply(sigmoid, final_add);
// begin backpropagation
Matrix* sigma = matrix_create(final_outputs->rows, 1);
matrix_fill(sigma, 1);
Matrix* temp1 = subtract(sigma, final_outputs);
Matrix* temp2 = multiply(temp1, final_outputs); // * soll-ist
Matrix* temp3 = matrix_create(final_outputs->rows, final_outputs->columns);
matrix_fill(temp3, 0);
temp3->numbers[label][0] = 1;
Matrix* temp4 = subtract(temp3, final_outputs);
sigma = multiply(temp2, temp4);
Matrix* temp5 = transpose(h3_outputs);
Matrix* temp6 = dot(sigma, temp5);
Matrix* weights_delta = scale(temp6, network->learning_rate);
Matrix* bias_delta = scale(sigma, network->learning_rate);
Matrix* temp7 = add(weights_delta, network->weights_output);
matrix_free(network->weights_output);
network->weights_output = temp7;
Matrix* temp8 = add(bias_delta, network->bias_output);
matrix_free(network->bias_output);
network->bias_output = temp8;
// other levels
backPropagation(network->learning_rate, network->weights_3, network->bias_3, h3_outputs, h2_outputs, sigma);
backPropagation(network->learning_rate, network->weights_2, network->bias_2, h2_outputs, h1_outputs, sigma);
backPropagation(network->learning_rate, network->weights_1, network->bias_1, h1_outputs, input, sigma);
matrix_free(input);
matrix_free(h1_dot);
matrix_free(h1_add);
matrix_free(h1_outputs);
matrix_free(h2_dot);
matrix_free(h2_add);
matrix_free(h2_outputs);
matrix_free(h3_dot);
matrix_free(h3_add);
matrix_free(h3_outputs);
matrix_free(final_dot);
matrix_free(final_add);
matrix_free(final_outputs);
matrix_free(weights_delta);
matrix_free(bias_delta);
matrix_free(sigma);
matrix_free(temp1);
matrix_free(temp2);
matrix_free(temp3);
matrix_free(temp4);
matrix_free(temp5);
matrix_free(temp6);
matrix_free(temp7);
matrix_free(temp8);
}
void backPropagation(double learning_rate, Matrix* weights, Matrix* biases, Matrix* current_layer_activation, Matrix* previous_layer_activation, Matrix* sigma_old) {
Matrix* sigma_new = matrix_create(current_layer_activation->rows, 1);
matrix_fill(sigma_new, 1);
Matrix* temp1 = subtract(sigma_new, current_layer_activation);
Matrix* temp2 = multiply(temp1, current_layer_activation); // *sum(delta*weights)
for(int i = 0; i < current_layer_activation->rows; i++) {
double sum = 0;
for (int j = 0; j < sigma_old->rows; j++) {
sum += current_layer_activation->numbers[i][j] * sigma_old->numbers[j][0];
}
temp1->numbers[i][0] = sum;
}
sigma_new = multiply(temp2, temp1);
// new sigma done
Matrix* temp3 = transpose(previous_layer_activation);
Matrix* temp4 = dot(sigma_new, temp3);
Matrix* weights_delta = scale(temp4, learning_rate);
Matrix* bias_delta = scale(sigma_new, learning_rate);
Matrix* temp5 = add(weights_delta, weights);
free(weights->numbers);
weights->numbers = temp5->numbers;
Matrix* temp6 = add(bias_delta, biases);
free(biases->numbers);
biases->numbers = temp6->numbers;
sigma_old->rows = sigma_new->rows;
sigma_old->columns = sigma_new->columns;
free(sigma_old->numbers);
sigma_old->numbers = sigma_new->numbers;
free(sigma_new);
matrix_free(temp1);
matrix_free(temp2);
matrix_free(temp3);
matrix_free(temp4);
matrix_free(temp5);
matrix_free(temp6);
matrix_free(weights_delta);
matrix_free(bias_delta);
}
//void batch_train_network(Neural_Network* network, Image** images, int size);
double sigmoid(double input) {
return 1.0 / (1 + exp(-1 * input));
}
double sigmoid_derivative(double x) {
return x * (1.0 - x);
}
Matrix* softmax(Matrix* matrix) {
double total = 0;
for (int i = 0; i < matrix->rows; i++) {
for (int j = 0; j < matrix->columns; j++) {
total += exp(matrix->numbers[i][j]);
}
}
Matrix* result_matrix = matrix_create(matrix->rows, matrix->columns);
for (int i = 0; i < result_matrix->rows; i++) {
for (int j = 0; j < result_matrix->columns; j++) {
result_matrix->numbers[i][j] = exp(matrix->numbers[i][j]) / total;
}
}
return result_matrix;
}
double square(double input) {
return input * input;
}
double loss_function(Matrix* output_matrix, int image_label) {
Matrix* temp = matrix_copy(output_matrix);
temp->numbers[1, image_label] -= 1;
apply(square, temp);
matrix_free(temp);
return matrix_sum(temp);;
}