BP算法学习
此源码只供学习只用，VC6.0下调试成功。
源码为转载别人博客。
权值最后无法求出，不知什么原因。
#include "stdlib.h"
#include "math.h"
#include "conio.h"
#include "stdio.h"
#define N 2 /*/学习样本个数*/
#define IN 3 /*/输入层神经元数目*/
#define HN 3 /*/隐层神经元数目*/
#define ON 2 /*/输出层神经元数目*/
#define Z 20 /*/旧权值保存-》每次study的权值都保存下来*/
double P[IN]; /*/单个样本输入数据*/
double T[ON]; /*/单个样本教师数据*/
double W[HN][IN]; /*/输入层至隐层权值*/
double V[ON][HN]; /*/隐层至输出层权值*/
double X[HN]; /*/隐层的输入*/
double Y[ON]; /*/输出层的输入*/
double H[HN]; /*/隐层的输出*/
double O[ON]; /*/输出层的输出*/
double YU_HN[HN]; /*/隐层的阈值*/
double YU_ON[ON]; /*/输出层的阈值*/
double err_m[N]; /*/第m个样本的总误差*/
double a; /*/输出层至隐层的学习效率*/
double b; /*/隐层至输入层学习效率*/
double alpha; /*/动量因子，改进型bp算法使用*/
double d_err[ON];
FILE *fp;
/*定义一个放学习样本的结构*/
struct {
double input[IN];
double teach[ON];
}Study_Data[N];
/*改进型bp算法用来保存每次计算的权值*/
struct {
double old_W[HN][IN];
double old_V[ON][HN];
}Old_WV[Z];
int Start_Show()
{
//clrscr();
printf("/n ***********************/n");
printf(" * Welcome to use */n");
printf(" * this program of */n");
printf(" * calculating the BP */n");
printf(" * model! */n");
printf(" * Happy every day! */n");
printf(" ***********************/n");
printf("/n/nBefore starting,please read the follows carefully:/n/n");
printf(" 1.Please ensure the Path of the '训练样本.txt'(xunlianyangben.txt) is /ncorrect,like 'F://BP//训练样本.txt'!/n");
printf(" 2.The calculating results will be saved in the Path of 'F://BP//'!/n");
printf(" 3.The program will load 10 datas when running from 'F://BP//训练样本.txt'!/n");
printf(" 4.The program of BP can study itself for no more than 30000 times./nAnd surpassing the number,the program will be ended by itself in/npreventing running infinitely because of error!/n");
printf("/n/n/n");
printf("Now press any key to start.../n");
getch();
getch();
//clrscr();
return 1;
}
int End_Show()
{
printf("/n/n---------------------------------------------------/n");
printf("The program has reached the end successfully!/n/nPress any key to exit!/n/n");
printf("/n ***********************/n");
printf(" * This is the end */n");
printf(" * of the program which*/n");
printf(" * can calculate the BP*/n");
printf(" * model! */n");
printf(" ***********************/n");
printf(" * Thanks for using! */n");
printf(" * Happy every day! */n");
printf(" ***********************/n");
getch();
exit(0);
}
int GetTrainingData() /*OK*/
{ int m,i,j;
int datr;
if((fp=fopen("f://bp//训练样本.txt","r"))==NULL) /*读取训练样本*/
{
printf("Cannot open file strike any key exit!");
getch();
exit(1);
}
m=0;
i=0;
j=0;
while(fscanf(fp,"%d",&datr)!=EOF)
{j++;
if(j<=(N*IN))
{
if(i<IN)
{
Study_Data[m].input[i]=datr;
/*printf("/nthe Study_Datat[%d].input[%d]=%f/n",m,i,Study_Data[m].input[i]);getch();*/ /*use to check the loaded training datas*/
}
if(m==(N-1)&&i==(IN-1))
{
m=0;
i=-1;
}
if(i==(IN-1))
{
m++;
i=-1;
}
}
else if((N*IN))
{
if(i<ON)
{
Study_Data[m].teach[i]=datr;
/*printf("/nThe Study_Data[%d].teach[%d]=%f",m,i,Study_Data[m].teach[i]);getch();*/ /*use to check the loaded training datas*/
}
if(m==(N-1)&&i==(ON-1))
printf("/n");
if(i==(ON-1))
{m++;
i=-1;
}
}
i++;
}
fclose(fp);
printf("/nThere are [%d] datats that have been loaded successfully!/n",j);
/*show the data which has been loaded!*/
printf("/nShow the data which has been loaded as follows:/n");
for(m=0;m<N;m++) {for(i=0;i<IN;i++) {printf("/nStudy_Data[%d].input[%d]=%f",m,i,Study_Data[m].input[i]);
}
for(j=0;j<ON;j++) {printf("/nStudy_Data[%d].teach[%d]=%f",m,j,Study_Data[m].teach[j]);
}
}
printf("/n/nPress any key to start calculating...");
getch();
return 1;
}
/*///////////////////////////////////*/
/*初始化权、阈值子程序*/
/*///////////////////////////////////*/
initial()
{int i;
int ii;
int j;
int jj;
int k;
int kk;
/*隐层权、阈值初始化*/
for(i=0;i<HN;i++) {
for(j=1;j<IN;j++) {W[i][j]=(double)((rand()/32767.0)*2-1); /*初始化输入层到隐层的权值，随机模拟0 和 1 -1 */
printf("w[%d][%d]=%f/n",i,j,W[i][j]);
}
}
for(ii=0;ii<ON;ii++) {
for(jj=0;jj<HN;jj++) {V[ii][jj]= (double)((rand()/32767.0)*2-1); /*初始化隐层到输出层的权值，随机模拟0 和 1 -1*/
printf("V[%d][%d]=%f/n",ii,jj,V[ii][jj]);
}
}
for(k=0;k<HN;k++) {
YU_HN[k] = (double)((rand()/32767.0)*2-1); /*隐层阈值初始化 ,-0.01 ~ 0.01 之间*/
printf("YU_HN[%d]=%f/n",k,YU_HN[k]);
}
for(kk=0;kk<ON;kk++) {
YU_ON[kk] = (double)((rand()/32767.0)*2-1); /*输出层阈值初始化 ,-0.01 ~ 0.01 之间*/
}
return 1;
}/*子程序initial()结束*/
/*//////////////////////////////////////////*/
/*第m个学习样本输入子程序*/
/*/////////////////////////////////////////*/
int input_P(int m)
{ int i;
for(i=0;i<IN;i++)
{
P[i]=Study_Data[m].input[i];
printf("P[%d]=%f/n",i,P[i]);
}
/*获得第m个样本的数据*/
return 1;
}/*子程序input_P(m）结束*/
/*/////////////////////////////////////////*/
/*第m个样本教师信号子程序*/
/*/////////////////////////////////////////*/
int input_T(int m)
{int k;
for(k=0;k<ON;k++) T[k]=Study_Data[m].teach[k];
return 1;
}/*子程序input_T(m)结束*/
int H_I_O()
{
double sigma;
int i,j;
for(j=0;j<HN;j++) {
sigma=0;
for(i=0;i<IN;i++) {sigma+=W[j][i]*P[i];/*求隐层内积*/
}
X[j]=sigma-YU_HN[i];/*求隐层净输入，为什么减隐层的阀值:神经网络*/
H[j]=1.0/(1.0+exp(-X[j]));/*求隐层输出 siglon算法*/
}
return 1;
}/*子程序H_I_O()结束*/
int O_I_O()
{int k;
int j;
double sigma;
for(k=0;k<ON;k++) {
sigma=0.0;
for(j=0;j<HN;j++) {
sigma+=V[k][j]*H[k];
}
Y[k]=sigma-YU_ON[k];
O[k]=1.0/(1.0+exp(-Y[k]));
}
return 1;
}
int Err_O_H(int m)
{int k;
double abs_err[ON];
double sqr_err=0;
for (k=0;k<ON;k++) {
abs_err[k]=T[k]-O[k];
sqr_err+=(abs_err[k])*(abs_err[k]);
d_err[k]=abs_err[k]*O[k]*(1.0-O[k]);
err_m[m]=sqr_err/2;
}
return 1;
}
double e_err[HN];
int Err_H_I()
{
int j,k;
double sigma;
for(j=0;j<HN;j++) {
sigma=0.0;
for(k=0;k<ON;k++) {
sigma=d_err[k]*V[k][j];
}
e_err[j]=sigma*H[j]*(1-H[j]);
}
return 1;
}
int saveWV(int m)
{int i;
int ii;
int j;
int jj;
for(i=0;i<HN;i++) {
for(j=0;j<IN;j++) {
Old_WV[m].old_W[i][j] = W[i][j];
}
}
for(ii=0;ii<ON;ii++) {
for(jj=0;jj<HN;jj++) {
Old_WV[m].old_V[ii][jj] = V[ii][jj];
}
}
return 1;
}
int Delta_O_H(int n) /*(int m,int n)*/
{int k,j;
if(n<=1) /*n<=1*/
{
for (k=0;k<ON;k++) {
for (j=0;j<HN;j++) {
V[k][j]=V[k][j]+a*d_err[k]*H[j];
}
YU_ON[k]+=a*d_err[k];
}
}
else if(n>1)
{
for (k=0;k<ON;k++) {
for (j=0;j<HN;j++) {
V[k][j]=V[k][j]+a*d_err[k]*H[j]+alpha*(V[k][j]-Old_WV[(n-1)].old_V[k][j]);
}
YU_ON[k]+=a*d_err[k];
}
}
return 1;
}
int Delta_H_I(int n) /*(int m,int n)*/
{ int i,j;
if(n<=1) /*n<=1*/
{
for (j=0;j<HN;j++) {
for (i=0;i<IN;i++) {
W[j][i]=W[j][i]+b*e_err[j]*P[i];
}
YU_HN[j]+=b*e_err[j];
}
}
else if(n>1)
{
for(j=0;j<HN;j++) {
for(i=0;i<IN;i++) {
W[j][i]=W[j][i]+b*e_err[j]*P[i]+alpha*(W[j][i]-Old_WV[(n-1)].old_W[j][i]);
}
YU_HN[j]+=b*e_err[j];
}
}
return 1;
}
double Err_Sum()
{int m;
double total_err=0;
for(m=0;m<HN;m++) {
total_err+=err_m[m];
}
return total_err;
}
void savequan()
{ int i,j,k;
int ii,jj,kk;
if((fp=fopen("f://bp//权值.txt","a"))==NULL) /*save the result at f:/hsz/bpc/*.txt*/
{
printf("Cannot open file strike any key exit!");
getch();
exit(1);
}
fprintf(fp,"Save the result of “权值”(quanzhi) as follows:/n");
for(i=0;i<HN;i++) {
for(j=0;j<IN;j++) fprintf(fp,"W[%d][%d]=%f/n",i,j,W[i][j]);
}
fprintf(fp,"/n");
for(ii=0;ii<ON;ii++) {
for(jj=0;jj<HN;jj++) fprintf(fp,"V[%d][%d]=%f/n",ii,jj,V[ii][jj]);
}
fclose(fp);
printf("/nThe result of “权值.txt”(quanzhi) has been saved successfully!/nPress any key to continue...");
getch();
if((fp=fopen("f://bp//阈值.txt","a"))==NULL) /*save the result at f:/hsz/bpc/*/
{
printf("Cannot open file strike any key exit!");
getch();
exit(1);
}
fprintf(fp,"Save the result of “输出层的阈值”(huozhi) as follows:/n");
for(k=0;k<ON;k++) fprintf(fp,"YU_ON[%d]=%f/n",k,YU_ON[k]);
fprintf(fp,"/nSave the result of “隐层的阈值为”(huozhi) as follows:/n");
for(kk=0;kk<HN;kk++) fprintf(fp,"YU_HN[%d]=%f/n",kk,YU_HN[kk]);
fclose(fp);
printf("/nThe result of “阈值.txt”(huozhi) has been saved successfully!/nPress any key to continue...");
getch();
}
/**********************/
/**程序入口，即主程序**/
/**********************/
void main()
{double Pre_error;
double sum_err;
int study;
int flag;
flag=30000;
a=0.7;
b=0.7;
alpha=0.9;
study=0;
Pre_error=0.0001;/*实际值为Pre_error=0.0001;*/
Start_Show();
GetTrainingData();
initial();
do
{int m;
++study;
for(m=0;m<N;m++) {
input_P(m);
input_T(m);
H_I_O();
O_I_O();
Err_O_H(m);
Err_H_I();
saveWV(m); /****************/
Delta_O_H(m); /*(m,study)*/
Delta_H_I(m); /*(m,study)*/
}
sum_err=Err_Sum();
printf("sum_err=%f/n",sum_err);
printf("Pre_error=%f/n/n",Pre_error);
if(study>flag)
{
printf("/n*******************************/n");
printf("The program is ended by itself because of error!/nThe learning times is surpassed!/n");
printf("*****************************/n");
getch();
break;
}
}while (sum_err>Pre_error);
printf("/n****************/n");
printf("/nThe program have studyed for [%d] times!/n",study);
printf("/n****************/n");
savequan(); /*save the results*/
End_Show();
}
下面是作者给的结果：
权值.txt
{Save the result of “权值”(quanzhi) as follows:
W[0][0]=0.350578
W[0][1]=-1.008697
W[0][2]=-0.962250
W[1][0]=0.055661
W[1][1]=-0.372367
W[1][2]=-0.890795
W[2][0]=0.129752
W[2][1]=-0.332591
W[2][2]=-0.521561
V[0][0]=-2.932654
V[0][1]=-3.720583
V[0][2]=-2.648183
V[1][0]=2.938970
V[1][1]=1.633281
V[1][2]=1.944077
}
阈值.txt
{Save the result of “输出层的阈值”(huozhi) as follows:
YU_ON[0]=-4.226843
YU_ON[1]=1.501791
Save the result of “隐层的阈值为”(huozhi) as follows:
YU_HN[0]=-0.431459
YU_HN[1]=0.452127
YU_HN[2]=0.258449
}