back_propagation.c

一个不错的GA-NN的神经网络模型的示范代码。适合入门学习

/*  back_propagation.c */

/* 	Copyright 2004 Oswaldo Morizaki */

/* 	This file is part of ga-nn-ag.

    ga-nn-ag is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    ga-nn-ag is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with ga-nn-ag; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "my_header.h"
#include "aux_prot.h"

int back_propagation(int num_neuron, struct neuron ** neuron_array, int num_elem_input, 
							float threshold_level)
{
	int k,l,m;
	float con_x, con_y;
	for (k=num_neuron-1; k>num_elem_input-1; k--)
	{
		for (l=0; l<neuron_array[k]->num_con; l++)
		{
			con_x=*(neuron_array[k]->con_x+l);
			con_y=*(neuron_array[k]->con_y+l);
			
			for (m=k-1; m+1 ;m--)
			{
				if( (con_x < neuron_array[m]->x_c + 0.001) &&
								(con_x > neuron_array[m]->x_c - 0.001) &&
								(con_y < neuron_array[m]->y_c + 0.001) &&
								(con_y > neuron_array[m]->y_c - 0.001) )
				break;
			}
			
			neuron_array[m]->delta += der(neuron_array[k]->delta_type,neuron_array[m]->value, 
													threshold_level)*
						(neuron_array[k]->delta)*
						*(neuron_array[k]->con_w+l);
						
//		syslog(LOG_INFO,"delta[%d] = %f",m,neuron_array[m]->delta);
		}
	}
	return(1);
}