C 實現神經BP神經網路

2021-09-22 07:50:19 字數 2790 閱讀 8329

bp.h

#pragma once


#include


#include


#include


#include


#include


using std:


:vector;


using std:


:exp;


using std:


:cout;


using std:


:endl;


class bp


;
bp.cpp

#include


"bp.h"


bp::


bp(vector<


int>


const


& layer_num, vectordouble


>>


const


& input,


vectordouble


>>


const


& output_y,


double hh,


double allerror,


int studynum)


a[0]= input;


studynum = studynum;


}bp::bp


(); a =


; y =


; h =0;


allowerror =0;


}bp::~


bp()void bp:


:setlayernuminput


(vector<


int>


const


& layer_num, vectordouble


>>


const


& input)


a[0]= input;


}void bp:


:setoutputy


(vectordouble


>>


const


& output_y)


void bp:


:setherrorstudynum


(double hh,


double allerror,


int studynum)


//初始化權重矩陣


void bp:


:iniwb()


}}void bp:


:inidwdb()


}}//啟用函式


double bp:


:sigmoid


(double z)


void bp:


:forward()


}}}void bp:


:backward()


//處理剩下層的權重w的增量dw


for(


int l = layernum.


size()


-2; l >


0; l--)}


}//計算dw與db平均值


for(


int l =


0; l < layernum.


size()


-1; l++)}


//更新引數w與b


for(


int l =


0; l < layernum.


size()


-1; l++)}


}double bp:


:error()


error = error / x[0]


.size()


;//求對每一組樣本的誤差平均


error = error /2;


cout << error << endl;


return error;


}//執行神經網路


void bp:


:run()


backward()


;}if(i ==


10000


) cout <<


"study failed!"


<< endl;


}vector<


double


> bp:


:predict


(vector<


double


>


& input)


return a1[layernum.


size()


-1];


}
驗證程式：

#include


"bp.h"


intmain()


; vectordouble


>> input_a0 =};


vectordouble


>> output_y =};


bp bp


(layer_num, input_a0,output_y,


0.6,


0.001


,2000);


bp.run();


for(


int j =


0; j <


30; j++);


vector<


double


> output = bp.


predict


(input)


;for


(auto i : output)


cout <<


"j:"


<<


0.5*j <<


" pridict:"


<< i <<


" ";


cout << endl;


}system


("pause");


return0;


}

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