bp.rar_BP神经网络

/* ****************************************************************** * backprop.cpp ****************************************************************** */ #include "StdAfx.h" #include <stdio.h> #include "backprop.h" #include <math.h> #include <stdlib.h> #define ABS(x) (((x) > 0.0) ? (x) : (-(x))) /* 宏定义：快速拷贝 */ #define fastcopy(to,from,len)\ {\ register char *_to,*_from;\ register int _i,_l;\ _to = (char *)(to);\ _from = (char *)(from);\ _l = (len);\ for (_i = 0; _i < _l; _i++) *_to++ = *_from++;\ } /*** 返回0－1的双精度随机数 ***/ double drnd() { return ((double) rand() / (double) BIGRND); } /*** 返回-1.0到1.0之间的双精度随机数 ***/ double dpn1() { return ((drnd() * 2.0) - 1.0); } /*** 作用函数，目前是S型函数 ***/ double squash(double x) { return (1.0 / (1.0 + exp(-x))); } /*** 申请1维双精度实数数组 ***/ double *alloc_1d_dbl(int n) { double *new1; new1 = (double *) malloc ((unsigned) (n * sizeof (double))); if (new1 == NULL) { printf("ALLOC_1D_DBL: Couldn't allocate array of doubles\n"); return (NULL); } return (new1); } /*** 申请2维双精度实数数组 ***/ double **alloc_2d_dbl(int m, int n) { int i; double **new1; new1 = (double **) malloc ((unsigned) (m * sizeof (double *))); if (new1 == NULL) { printf("ALLOC_2D_DBL: Couldn't allocate array of dbl ptrs\n"); return (NULL); } for (i = 0; i < m; i++) { new1[i] = alloc_1d_dbl(n); } return (new1); } /*** 随机初始化权值 ***/ void bpnn_randomize_weights(double **w, int m, int n) { int i, j; for (i = 0; i <= m; i++) { for (j = 0; j <= n; j++) { w[i][j] = dpn1(); } } } /*** 0初始化权值 ***/ void bpnn_zero_weights(double **w, int m, int n) { int i, j; for (i = 0; i <= m; i++) { for (j = 0; j <= n; j++) { w[i][j] = 0.0; } } } /*** 设置随机数种子 ***/ void bpnn_initialize(int seed) { printf("Random number generator seed: %d\n", seed); srand(seed); } /*** 创建BP网络 ***/ BPNN *bpnn_internal_create(int n_in, int n_hidden, int n_out) { BPNN *newnet; newnet = (BPNN *) malloc (sizeof (BPNN)); if (newnet == NULL) { printf("BPNN_CREATE: Couldn't allocate neural network\n"); return (NULL); } newnet->input_n = n_in; newnet->hidden_n = n_hidden; newnet->output_n = n_out; newnet->input_units = alloc_1d_dbl(n_in + 1); newnet->hidden_units = alloc_1d_dbl(n_hidden + 1); newnet->output_units = alloc_1d_dbl(n_out + 1); newnet->hidden_delta = alloc_1d_dbl(n_hidden + 1); newnet->output_delta = alloc_1d_dbl(n_out + 1); newnet->target = alloc_1d_dbl(n_out + 1); newnet->input_weights = alloc_2d_dbl(n_in + 1, n_hidden + 1); newnet->hidden_weights = alloc_2d_dbl(n_hidden + 1, n_out + 1); newnet->input_prev_weights = alloc_2d_dbl(n_in + 1, n_hidden + 1); newnet->hidden_prev_weights = alloc_2d_dbl(n_hidden + 1, n_out + 1); return (newnet); } /* 释放BP网络所占地内存空间 */ void bpnn_free(BPNN *net) { int n1, n2, i; n1 = net->input_n; n2 = net->hidden_n; free((char *) net->input_units); free((char *) net->hidden_units); free((char *) net->output_units); free((char *) net->hidden_delta); free((char *) net->output_delta); free((char *) net->target); for (i = 0; i <= n1; i++) { free((char *) net->input_weights[i]); free((char *) net->input_prev_weights[i]); } free((char *) net->input_weights); free((char *) net->input_prev_weights); for (i = 0; i <= n2; i++) { free((char *) net->hidden_weights[i]); free((char *) net->hidden_prev_weights[i]); } free((char *) net->hidden_weights); free((char *) net->hidden_prev_weights); free((char *) net); } /*** 创建一个BP网络，并初始化权值 ***/ BPNN *bpnn_create(int n_in, int n_hidden, int n_out) { BPNN *newnet; newnet = bpnn_internal_create(n_in, n_hidden, n_out); #ifdef INITZERO bpnn_zero_weights(newnet->input_weights, n_in, n_hidden); #else bpnn_randomize_weights(newnet->input_weights, n_in, n_hidden); #endif bpnn_randomize_weights(newnet->hidden_weights, n_hidden, n_out); bpnn_zero_weights(newnet->input_prev_weights, n_in, n_hidden); bpnn_zero_weights(newnet->hidden_prev_weights, n_hidden, n_out); return (newnet); } void bpnn_layerforward(double *l1, double *l2, double **conn, int n1, int n2) { double sum; int j, k; /*** 设置阈值 ***/ l1[0] = 1.0; /*** 对于第二层的每个神经元 ***/ for (j = 1; j <= n2; j++) { /*** 计算输入的加权总和 ***/ sum = 0.0; for (k = 0; k <= n1; k++) { sum += conn[k][j] * l1[k]; } l2[j] = squash(sum); } } /* 输出误差 */ void bpnn_output_error(double *delta, double *target, double *output, int nj, double *err) { int j; double o, t, errsum; errsum = 0.0; for (j = 1; j <= nj; j++) { o = output[j]; t = target[j]; delta[j] = o * (1.0 - o) * (t - o); errsum += ABS(delta[j]); } *err = errsum; } /* 隐含层误差 */ void bpnn_hidden_error(double* delta_h, int nh, double *delta_o, int no, double **who, double *hidden, double *err) { int j, k; double h, sum, errsum; errsum = 0.0; for (j = 1; j <= nh; j++) { h = hidden[j]; sum = 0.0; for (k = 1; k <= no; k++) { sum += delta_o[k] * who[j][k]; } delta_h[j] = h * (1.0 - h) * sum; errsum += ABS(delta_h[j]); } *err = errsum; } /* 调整权值 */ void bpnn_adjust_weights(double *delta, int ndelta, double *ly, int nly, double** w, double **oldw, double eta, double momentum) { double new_dw; int k, j; ly[0] = 1.0; for (j = 1; j <= ndelta; j++) { for (k = 0; k <= nly; k++) { new_dw = ((eta * delta[j] * ly[k]) + (momentum * oldw[k][j])); w[k][j] += new_dw; oldw[k][j] = new_dw; } } } /* 进行前向运算 */ void bpnn_feedforward(BPNN* net) { int in, hid, out; in = net->input_n; hid = net->hidden_n; out = net->output_n; /*** Feed forward input activations. ***/ bpnn_layerforward(net->input_units, net->hidden_units, net->input_weights, in, hid); bpnn_layerforward(net->hidden_units, net->output_units, net->hidden_weights, hid, out); } /* 训练BP网络 */ void bpnn_train(BPNN *net, double eta, double momentum, double *eo, double *eh) { int in, hid, out; double out_err, hid_err; in = net->input_n; hid = net->hidden_n; out = net->output_n; /*** 前向输入激活 ***/ bpnn_layerforward(net->input_units, net->hidden_units, net->input_weights, in, hid); bpnn_layerforward(net->hidden_units, net->output_u