Question

我已经编写或者更愿意使用ZedGraph在C＃中绘制自由空间薛定谔方程，并在运行创建的可执行文件时遇到System.OutOfMemoryException错误。

************** Exception Text **************
System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
   at System.Collections.Generic.List`1.set_Capacity(Int32 value)
   at System.Collections.Generic.List`1.EnsureCapacity(Int32 min)
   at System.Collections.Generic.List`1.Add(T item)
   at ZedGraph.PointPairList.Add(Double x, Double y)
   at Wavepacket.Form1.CreateGraph(ZedGraphControl schrodinger) in C:\Users\user1748005\Documents\Visual Studio 2010\Projects\Wavepacket\Wavepacket\Form1.cs:line 72
   at Wavepacket.Form1.Form1_Load(Object sender, EventArgs e) in C:\Users\user1748005\Documents\Visual Studio 2010\Projects\Wavepacket\Wavepacket\Form1.cs:line 35
   at System.Windows.Forms.Form.OnLoad(EventArgs e)
   at System.Windows.Forms.Form.OnCreateControl()
   at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
   at System.Windows.Forms.Control.CreateControl()
   at System.Windows.Forms.Control.WmShowWindow(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at System.Windows.Forms.Form.WmShowWindow(Message& m)
   at System.Windows.Forms.Form.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

我的Cmplx类的必要函数/构造函数相对简单，并且是这样的：

    public Cmplx(double r, double i)
    {
        this.real = r;
        this.imag = i;
    }

    public double Real
    {
        get { return this.real; }
        set { this.real = value; }
    }

    public double Imag
    {
        get { return this.imag; }
        set { this.imag = value; }
    }
    public Cmplx Multiply(Cmplx b)
    {
        return new Cmplx((this.real * b.real - this.imag * b.imag), (b.imag * this.real + this.imag * b.real));
    }

    public Cmplx Divide(Cmplx b)
    {
        return new Cmplx((this.real * b.real + this.imag * b.imag) / (b.real * b.real + b.imag * b.imag), (b.real * this.imag - this.real * b.imag) / (b.real * b.real + b.imag * b.imag));
    }

    public Cmplx Scale(Double b)
    {
        return new Cmplx(this.real * b, this.imag * b);
    }

    public double Mod()
    {
        return Math.Sqrt(this.real * this.real + this.imag * this.imag);
    }

    public Cmplx Sqrt()
    {
        double r, theta;
        r = this.Mod();
        theta = this.Arg();

        return new Cmplx(Math.Sqrt(r) * (Math.Cos(theta / 2)), Math.Sqrt(r) * Math.Sin(theta / 2));
    }

    public Cmplx Exp()
    {
        double x, y, z;
        x = Math.Exp(this.real);
        y = Math.Cos(this.imag);
        z = Math.Sin(this.imag);

        return new Cmplx(x * y, x * z);
    }

下面是我的ZedGraph方法，只有从Codeproject ZedGraph教程修改的CreateGraph方法：

    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Resize(object sender, EventArgs e)
    {
        SetSize();
    }

    private void SetSize()
    {
        zedGraphControl1.Location = new Point(10, 10);
        zedGraphControl1.Size = new Size(ClientRectangle.Width - 20,
                                ClientRectangle.Height - 20);
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        CreateGraph(zedGraphControl1);
        SetSize();
    }

    private void CreateGraph(ZedGraphControl schrodinger)
    {
        GraphPane myPane = schrodinger.GraphPane;

        myPane.Title.Text = "Free Space Schrodinger Equation)";
        myPane.XAxis.Title.Text = "Time (s)";
        myPane.YAxis.Title.Text = "Psi";

        double alpha, beta, norm, k0, t;
        double L,N;

        L = 25;
        N = 4096;
        alpha = 0.5;
        beta = 0.5785;  
        k0 = 1;
        t = 0;
        norm = (Math.Exp(-k0 * k0 * alpha)) * (Math.Pow((alpha / (2 * Math.PI)), 0.25));

        PointPairList list1 = new PointPairList();

        for (double i = -L; i <= L; i -= (-2L) / N)
        {
            Cmplx gamma = new Cmplx(alpha, beta * t);
            Cmplx a = new Cmplx(2 * alpha * k0, 0);
            a.Imag = i;
            Cmplx b = a.Multiply(a);
            Cmplx phi = (((b.Divide(gamma.Scale(4))).Exp()).Scale(norm)).Divide(gamma.Sqrt());
            list1.Add(phi.Mod(),i);
        }

        LineItem myCurve = myPane.AddCurve("t=0",
              list1, Color.Red, SymbolType.Default);
        schrodinger.AxisChange();
    }

我已经改变了

list1.Add(phi.Mod(), i);

将上述代码块的for循环中的行转换为

Console.WriteLine("{0}, {1}", phi.Mod(), i);

虽然在命令行界面中，但仍然可以正常工作。在抛出上述异常之前，使用ZedGraph库结果的Windows窗体应用程序消耗约1.7GB的RAM。

我通过绘制大量数据点找到了ZedGraph内存不足的实例

Charting massive amounts of data

然而，我不太倾向于我的微弱4096数据点的情节会导致这种内存消耗而宁愿错误（缺乏）编程技巧

NB ：这是一项学术任务，因此所提供的任何帮助都应考虑到这一点。干杯！

编辑：修正了L和N的初始化，而不是双精度。如前所述，问题仍然存在。

EDIT2 我是个白痴。我在我的测试CLI项目中将L和N的初始化更改为双精度但未能更新Windows窗体应用程序的源代码。感谢Jeppe Stig Nielsen指出我正确的方向。

Answer 1

检查for循环。看起来有一个减去（-）太多了。

此外，您的部门(-2*L) / N（缺少星号*）会给出零，因为它是整数除法。要解决这个问题，请将一个因素投射到double，或者只写：

2.0 * L / N

请注意，.0表示浮点数（System.Double），这将强制执行“步骤”的整个计算，并根据需要使用浮点数。

总结：如果您的步数为零，或者方向错误，您将继续向list1添加点，直到内存不足为止。也许这个for循环更好（但是自己测试一下）：

for (double i = -L; i <= L; i += (2.0 * L) / N)

ZedGraph情节：抛出System.OutOfMemoryException

1 个答案: