circuedlg.cpp

利用蒙特卡洛方法求圆周率的原程序

// circueDlg.cpp : implementation file
//

#include "stdafx.h"
#include "circue.h"
#include "circueDlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About

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

// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA

	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL

// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};

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

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

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CCircueDlg dialog

CCircueDlg::CCircueDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CCircueDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CCircueDlg)
	m_avNum = 0;
	m_circum = 0.0;
	m_doNum = 0;
	m_err = 0.0;
	m_number = 2000;
	//m_stat = _T("");
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CCircueDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CCircueDlg)
	DDX_Control(pDX, IDC_PRO, m_pro);
	DDX_Control(pDX, IDC_PICTURE, m_picture);
	//DDX_Text(pDX, IDC_STAT, m_stat);
	DDX_Text(pDX, IDC_AVNUM, m_avNum);
	DDX_Text(pDX, IDC_CirCUM, m_circum);
	DDX_Text(pDX, IDC_DONUM, m_doNum);
	DDX_Text(pDX, IDC_ERR, m_err);
	DDX_Text(pDX, IDC_NUMBER, m_number);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CCircueDlg, CDialog)
	//{{AFX_MSG_MAP(CCircueDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_AgAIN, OnAgAIN)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CCircueDlg message handlers

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

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	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);
		}
	}

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	
	//get the max_rand/2
	max = RAND_MAX/2.0;
	
	//m_number = 200000;
	// TODO: Add extra initialization here
	
	return TRUE;  // return TRUE  unless you set the focus to a control
}

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

// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.

void CCircueDlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		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;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CCircueDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

void CCircueDlg::Count()
{
	double a; //临时变量，用来计算随机数的半径
	this->DrawPicture ( TRUE, TRUE ); //显示图象
	this->UpdateData ( TRUE ); //得到数据，用当前框中的数据，来计算概率
	m_pro.SetRange32 (0,m_number); //设置进度条的范围
	m_avNum = 0; //将命中的次数设置为0
	for ( int i=1; i<=m_number; i++ ) //开始循环
	{
		randy = ( max - rand() )/max; //得到随机数，具体的方法，是利用计算机中存在的rand()
		randx = ( max - rand() )/max; //得到随机数
		a = randy*randy+randx*randx;  //得到随机数的半径
		if ( a<=1 )  //判断
		{
			m_avNum = m_avNum++; //符合条件 命中点+1
			this->DrawPicture ( TRUE, FALSE ); //显示图象
		}
		else
			this->DrawPicture ( FALSE, FALSE ); //不符合条件，显示图象
		m_pro.SetPos ( i );  //设置进度条当前位置
	}
	m_doNum = m_number; //运行次数为设置的次数
	m_circum = (double)(m_avNum); //改变整数为小数型
	m_circum = 4*m_circum / m_doNum; //计算圆周率
	m_err = 3.1415926 - m_circum; //圆周率与现在的圆周率的误差
	this->UpdateData ( FALSE );  //显示运算的结果
}

void CCircueDlg::DrawPicture( BOOL av, BOOL first )
{
	if ( first ) //如果是第一次，做图象数据处理的初始工作
	{
		hdc = ::GetDC ( m_picture.m_hWnd ); //得到句柄
		::GetClientRect ( m_picture.m_hWnd, &rect ); //得到图象区的大小
		rect.bottom = rect.bottom -20; 
		rect.top = rect.top +20;
		rect.left = rect.left + 20;
		rect.right = rect.right - 20; //以上为不让图象区走初边界
		c_x = ( rect.left + rect.right )/2;
		c_y = ( rect.bottom + rect.top )/2;  //以上为设置图象区的中点
		if ( (rect.bottom-rect.top)<(rect.right-rect.left) )
		{
			dir = rect.bottom - rect.top;
			rect.left = c_x - dir/2;
			rect.right = c_x + dir/2;
		}
		else
		{
			dir = rect.right - rect.left;
			rect.bottom = c_y + dir/2;
			rect.top = c_y - dir/2;
		}//设置显示四方区的边界
		::Rectangle ( hdc, rect.left, rect.top, rect.right, rect.bottom );//画出图象显示区
		return;//返回
	}
	if ( av )
		::SetPixel ( hdc, c_x + randx*dir/2, c_y + randy*dir/2, RGB ( 0, 0, 255 ) );//如果在圆半径内，显示为兰色点
	else
		::SetPixel ( hdc, c_x + randx*dir/2, c_y + randy*dir/2, RGB ( 255, 0, 0 ) );//如果不在圆的半径内，显示为红色点
}

void CCircueDlg::OnAgAIN() 
{
	// TODO: Add your control notification handler code here
	this->Count();
}