Exemple #1
0
        protected void Start()
        {
            this.simplex = new DownhillSimplex <float>(this.p, new Delta(), this.mode);

            this.simplex.End((p, s, dt, a) =>
            {
                LogTool.Log("Solution: ", LogLevel.Info);
                var sol = s as DownhillSimplex <float> .Solution;
                sol.min.Print();
                LogTool.Log("Running count: " + (dt as Delta).count);
            });

            this.simplex.TryToRun();
        }
Exemple #2
0
    static void Main()
    {
        Func <vector, double> rosenBrock = delegate(vector z){
            double x = z[0], y = z[1];
            return(Pow(1 - x, 2) + 100 * Pow(y - x * x, 2));
        };
        vector p   = new vector(0.0, 0.0);
        double eps = 1.0 / 1000;

        (vector roots, int steps) = qNewton(rosenBrock, p, eps);
        WriteLine("--- Part A ---");
        WriteLine("Searching for a minimum of the Rosenbrock Valley function...");
        p.print("Starting point:");
        roots.print($"Minimum found ({steps} steps)");
        WriteLine("Global minimum: (1,1)");

        Func <vector, double> himmelblau = delegate(vector z){
            double x = z[0], y = z[1];
            return(Pow(x * x + y - 11, 2) + Pow(x + y * y - 7, 2));
        };

        p              = new vector(0.0, 0.0);
        eps            = 1.0 / 1000;
        (roots, steps) = qNewton(himmelblau, p, eps);
        WriteLine("Searching for a minimum of the Himmelblau function...");
        p.print("Starting point:");
        roots.print($"Minimum found ({steps} steps)");
        WriteLine("Local minimum: (3,2)");

        WriteLine("\n\n--- Part B ---");
        // Read higgs.txt for fitting data
        StreamReader Reader = new StreamReader("higgs.txt");
        int          n = 30;
        vector       E = new vector(n), sigma = new vector(n), err = new vector(n);

        for (int i = 0; i < n; i++)
        {
            string    line = Reader.ReadLine();
            string [] data = line.Split(new char [] { ' ' });
            E[i] = (Double.Parse(data[0]));
            if (data[1] == "")
            {
                sigma[i] = Double.Parse(data[2]);
                err[i]   = Double.Parse(data[3]);
            }
            else
            {
                sigma[i] = (Double.Parse(data[1]));
                err[i]   = (Double.Parse(data[2]));
            }
        }
        Reader.Close();

        Func <double, double, double, double, double> breitWigner = (e, m, g, a) =>
                                                                    a / (Pow(e - m, 2) + g * g / 4);

        Func <vector, double> deviation = delegate(vector z){
            double m     = z[0];
            double gamma = z[1];
            double A     = z[2];
            double sum   = 0;
            for (int i = 0; i < n; i++)
            {
                sum += Pow(breitWigner(E[i], m, gamma, A) - sigma[i], 2);
            }
            return(sum);
        };

        p = new vector(125, 2, 6);
        vector min;

        (min, steps) = qNewton(deviation, p, eps);
        WriteLine($"Fitting Higgs data to Breit-Wigner function, done in {steps} steps.");
        WriteLine($"Found parameters:");
        WriteLine($"Mass: {min[0]} \nGamma: {min[1]} \nA: {min[2]}");

        WriteLine("\n\n--- Part C ---");
        WriteLine("Find minimum Rosenbrock Valley function...");
        p   = new vector(0.0, 0.0);
        eps = 1e-3;
        DownhillSimplex DHS = new DownhillSimplex(rosenBrock, p, eps);

        DHS.x.print($"Minimum found ({DHS.steps} steps):");
    }