FFT理论 　　

系统教程　　

曲线拟合：

1）线性多项式

double[] abc = Fit.LinearCombination(x1, y1, t => 1, t => Math.Pow(t, -2.0), t => Math.Pow(t, 2.0));

2）任意函数

double a = 5.8;            double b = 10.7;            double[] x1 = new double[100];            double[] y1 = new double[100];            Random rd = new Random(DateTime.Now.Millisecond);            int i;            for (i = 0; i < x1.Length; i++)            {                x1[i] = (rd.NextDouble()+0.001) * 20.0;                y1[i] = a * x1[i]+(rd.NextDouble()-0.5)*10.0;                    //b / (Math.Pow(1 + a * x1[0] * x1[0], 5 / 6)) + (rd.NextDouble() - 0.5) * 10.0;            }            Func
     
       fun = new Func
      
       (geab);            double dd = Fit.Curve(x1,y1,geab,3.0);        public double geab(double aa, double bb)        {            double dd;            dd =  aa*bb;            return dd;        }