plot2dlg.cpp

用mente－calo法算三维积分： 工作平台是：vs2002（7.0） MFC

// plot2Dlg.cpp : 实现文件
//

#include "stdafx.h"
#include "plot2.h"
#include "plot2Dlg.h"
#include "math.h"
#include <sys/timeb.h>
#include <time.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#endif


// 用于应用程序“关于”菜单项的 CAboutDlg 对话框

class CAboutDlg : public CDialog
{
public:
	CAboutDlg();

// 对话框数据
	enum { IDD = IDD_ABOUTBOX };

	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV 支持

// 实现
protected:
	DECLARE_MESSAGE_MAP()
};

CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
}

void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
}

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
END_MESSAGE_MAP()


// Cplot2Dlg 对话框



Cplot2Dlg::Cplot2Dlg(CWnd* pParent /*=NULL*/)
	: CDialog(Cplot2Dlg::IDD, pParent)
{
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void Cplot2Dlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
}

BEGIN_MESSAGE_MAP(Cplot2Dlg, CDialog)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	//}}AFX_MSG_MAP
	ON_BN_CLICKED(IDC_BUTTON_PAINT, OnBnClickedButtonPaint)
END_MESSAGE_MAP()


// Cplot2Dlg 消息处理程序

BOOL Cplot2Dlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// 将\“关于...\”菜单项添加到系统菜单中。

	// IDM_ABOUTBOX 必须在系统命令范围内。
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}

	// 设置此对话框的图标。当应用程序主窗口不是对话框时，框架将自动
	//  执行此操作
	SetIcon(m_hIcon, TRUE);			// 设置大图标
	SetIcon(m_hIcon, FALSE);		// 设置小图标

	// TODO：在此添加额外的初始化代码
	
	return TRUE;  // 除非设置了控件的焦点，否则返回 TRUE
}

void Cplot2Dlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}

// 如果向对话框添加最小化按钮，则需要下面的代码
//  来绘制该图标。对于使用文档/视图模型的 MFC 应用程序，
//  这将由框架自动完成。

void Cplot2Dlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // 用于绘制的设备上下文

		SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);

		// 使图标在工作矩形中居中
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// 绘制图标
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

//当用户拖动最小化窗口时系统调用此函数取得光标显示。


HCURSOR Cplot2Dlg::OnQueryDragIcon()
{
	return static_cast<HCURSOR>(m_hIcon);
}

double fc(double x)
{
	return exp((-1)*x*x/2)*(x*x);
}

double area()
{
	double rf;
	int i,j;
	double xr[10000],yr[10000];
	srand((unsigned)time(NULL));
	for(i=0;i<10000;i=i+1)
	{
		rf=((double)rand())/RAND_MAX*10-5;
		xr[i]=rf;
	}
	
	Sleep(1234);

	srand((unsigned)time(NULL));
	for(i=0;i<10000;i=i+1)
	{
		rf=((double)rand())/RAND_MAX;
		yr[i]=rf;
	}

	double csum=0;
    for(i=0;i<10000;i++)
	{
		for(j=0;j<10000;j++)
		{
			if(fc(xr[i])>yr[j])
			{
				csum++;
			}
		}
	}
    
	double area=csum/100000000*10;
	return area;
}

void drawArrow(int x,int y,CWnd *pWnd)
{
	CPoint pt;
	CDC *pDC;
    int xorg,yorg;
	pDC=pWnd->GetDC();
	pt=pDC->GetCurrentPosition();
	xorg=pt.x;
	yorg=pt.y;
	pDC->LineTo(xorg-x,yorg-y);
}
void Cplot2Dlg::OnBnClickedButtonPaint()
{
	// TODO: 在此添加控件通知处理程序代码
	CWnd *pWnd=NULL;
	pWnd=new CWnd();
	pWnd->CreateEx(WS_EX_CLIENTEDGE,AfxRegisterWndClass(0,::LoadCursor(NULL,IDC_ARROW),(HBRUSH)(COLOR_WINDOW+1)),"window",WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,0);

	pWnd->ShowWindow(SW_SHOW);
	pWnd->UpdateWindow();

	CDC *pDC=NULL;
	pDC=pWnd->GetDC();
	CPen p;
	p.CreatePen(PS_SOLID,1,RGB(0,0,0));
	CGdiObject *pOld=NULL;
	pOld=pDC->SelectObject(&p);
	pDC->MoveTo(100,100-100*fc(-10));

	for(double i=-100;i<100;i++)
	{
		pDC->LineTo(i+200,100-100*fc(i/10));
	}
	
	CString str;
	str.Format("When x is sqrt(2),the function gets the max value : %f",fc(sqrt(2)));
	pDC->TextOut(100,200,str);

	double fcmin_x;
	for(double j=sqrt(2);fc(j)/fc(sqrt(2))>0.001;j=j+0.02)
	{
		fcmin_x=j;
	}

	str.Format("When x is %f, value of the function is small enough:%f",fcmin_x,fc(fcmin_x));
	pDC->TextOut(100,220,str);
    
	double sum=0;
	for(double k=-5;k<=5;k=k+0.0001)
	{
		sum=sum+0.0001*fc(k);
	}
	
	str.Format("x的积分值(分段积分):%f",sum);
	pDC->TextOut(100,240,str);
/*
	str.Format("0x7fff=%u",0x7fff);
	pDC->TextOut(100,260,str);

	str.Format("0x7fff等于2的%f次方",log(7*16*16*16+15*16*16+15*16+16)/log(2));
	pDC->TextOut(100,280,str);
*/
/*
	srand((unsigned)time(NULL));
	for(i=0;i<100;i=i+1)
	{
		rf=((double)rand())/RAND_MAX*100-50;
	}
*/
	str.Format("x的积分值(monte-kalo):%f",area(),3);
	pDC->TextOut(100,260,str);

	str.Format("积分值(monte-calo):%f",pow(area(),3));
	pDC->TextOut(100,280,str);

	pDC->SelectObject(pOld);

}