#include
#include
#include
#include
using?namespace?std;

#define?NH????????2
#define?STEP??????1
double?**ppData;??????????//data
double??*pY;??????????????//std?result
double??*pOut;????????????//ouput
double?**ppIn;????????????//
double?**WeightIn;????????//hidden?note?weight
double??*WeightOut;???????//output?note?weight
double?**DWin;????????????//last?time?hidden?note?weight
double??*DWout;???????????//last?time?output?note?weight
double??Con_b[NH+1];
int?DataNum;???????????????//?data?number
int?Dimension;?????????????//?dimension
double?Threshhold;?????????//?sheld?

double?Sigmoid（double?x）
{
	return?1.0/（1+exp（-x））;
}
double?DotProduct（double*?vec1double?*vec2int?dim）
{
	double?result=0.0;
	for（int?i=0;i	{
		result+=vec1[i]*vec2[i];
	}
	return?result;
}
//compute?the?output?each?step
void?ComputeOutput（）
{
	for（int?i=0;i	{
		for（int?j=0;j		{
			double?dp=DotProduct（ppData[i]WeightIn[j]Dimension）;
			dp+=Con_b[j];
			ppIn[i][j]=Sigmoid（dp）;
		}
	}
	for（int?i=0;i	{
		double?dp=DotProduct（ppIn[i]WeightOutNH）;
		dp+=Con_b[NH];
		pOut[i]=Sigmoid（dp）;
	}
}
//update?weights?matrix
void?UpdateW（）
{
	double???DegreeIn[NH];
	double???DegreeOut=0;
	for（int?i=0;i	{
		for（int?j=0;j		{
			DWin[i][j]=0;
		}
		DWout[i]=0;
	}
	for（int?i=0;i	{
		DegreeOut=pOut[i]*（1-pOut[i]）*（pY[i]-pOut[i]）;
		for（int?h=0;h		{
			DegreeIn[h]=ppIn[i][h]*（1-ppIn[i][h]）*WeightOut[h]*DegreeOut;
			Con_b[h]+=STEP*DegreeIn[h];
		}
		Con_b[NH]+=STEP*DegreeOut;
		for（int?j=0;j		{
			DWout[j]+=STEP*DegreeOut*ppIn[i][j];
			//cout<		}
		for（int?x=0;x		{
			for（int?y=0;y			{
				DWin[x][y]+=STEP*DegreeIn[x]*ppData[i][y];
			}
		}
	}
	for（int?k=0;k	{
		for（int?j=0;j		{
			WeightIn[k][j]+=DWin[k][j];
			//cout<		}
		WeightOut[k]+=DWout[k];
		//cout<	}
	//cout<}
double?GetError（）
{
	double?e=0.0;
	for（int?i=0;i	{
		e+=（pY[i]-pOut[i]）*（pY[i]-pOut[i]）/2;
	}
	return?e;
}
void?Train（）
{
	double?error=100000;
	int?t=0;
	do{
		UpdateW（）;
		ComputeOutput（）;
		error=GetError（）;
		//
		t++;
	}while（error>Threshhold&&t<2000）;
????cout<	for（int?i?=?0;i?	{
	???cout<	}
	cout<}
double?*GetResult（double?thresh）
{
	for（int?i=0;i	{
		for（int?j=0;j		{
			double?dp=DotProduct（ppData[i]WeightIn[j]Dimension）;
			dp+=Con_b[j];
			ppIn[i][j]=Sigmoid（dp）;
		}
	}
	for（int?i=0;i	{
		double?dp=DotProduct（ppIn[i]WeightOutNH）;
		dp+=Con_b[NH];
		pY[i]=Sigmoid（dp）;
		if（pY[i]>thresh）
		{
			pY[i]=1;
		}
		else?pY[i]=0;
	}
	return?pY;
}
bool?Init（double?**datadouble?*yint?numint?dimdo

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????6369??2009-11-28?16:05??Backpropagation\backpropagation.cpp

?????文件??????25639??2009-11-28?16:04??Backpropagation\readme.docx

?????目錄??????????0??2009-11-28?16:05??Backpropagation

-----------?---------??----------?-----??----

????????????????32008????????????????????3