generatemodel.cpp

成本预测系统

// GenerateModel.cpp: implementation of the GenerateModel class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Predict.h"
#include "GenerateModel.h"
#include "DataConn.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

GenerateModel::GenerateModel()
{

}

GenerateModel::~GenerateModel()
{

}
//从数据库中读出数据放到数组中
void GenerateModel::ReadDatabase()
{
	DataConn dataconn;
	_bstr_t sql="select * from dataTable";
	dataconn.DataInit();
	_RecordsetPtr recordSet=dataconn.GetRecordset(sql);
    num=0;
	while(!recordSet->adoEOF)
	{
		tempx[num]=atof((LPSTR)(_bstr_t)(recordSet->GetCollect("input")));
		tempy[num]=atof((LPSTR)(_bstr_t)(recordSet->GetCollect("out")));
		recordSet->MoveNext();
		num++;
	}
	dataconn.ExitSql();

}
void GenerateModel::Generate()
{
    float sumx=0;
	float sumy=0;
	float sumx2=0;
	float sumxy=0;
	//循环求和
	for (int j=0;j<num;j++)
	{
		sumx=sumx+tempx[j];
		sumx2=sumx2+tempx[j]*tempx[j];
		sumy=sumy+tempy[j];
		sumxy=sumxy+tempx[j]*tempy[j];
	}
	/*CString temp1;
	temp1.Format("%d",num);
	AfxMessageBox(temp1);*/
	a=(sumx2*sumy-sumx*sumxy)/(num*sumx2-sumx*sumx);
	b=(num*sumxy-sumx*sumy)/(num*sumx2-sumx*sumx);
}
float GenerateModel::GetA()
{
	return a;
}
float GenerateModel::GetB()
{
	return b;
}