///
    ///用最小二乘法拟合二元多次曲线    ///
    ///已知点的x坐标集合    ///已知点的y坐标集合    ///已知点的个数    ///方程的最高次数       public static double[] MultiLine(double[] arrX, double[] arrY, int length, int dimension)//二元多次线性方程拟合曲线    {        int n = dimension + 1;                  //dimension次方程需要求 dimension+1个 系数        double[,] Guass=new double[n,n+1];      //高斯矩阵 例如：y=a0+a1*x+a2*x*x        for(int i=0;i
     
       max)                {                    max = Guass[i, j];                    k = i;                }            }                       if (k != j)            {                for (m = j; m < n + 1; m++)                {                    temp = Guass[j, m];                    Guass[j, m] = Guass[k, m];                    Guass[k, m] = temp;                }            }            if (0 == max)            {                // "此线性方程为奇异线性方程"                 return x;            }                       for (i = j + 1; i < n; i++)             {                s = Guass[i, j];                for (m = j; m < n + 1; m++)                {                    Guass[i, m] = Guass[i, m] - Guass[j, m] * s / (Guass[j, j]);                }            }        }//结束for (j=0;j
      
       = 0; i--)        {                       s = 0;            for (j = i + 1; j < n; j++)            {                s = s + Guass[i,j] * x[j];            }            x[i] = (Guass[i,n] - s) / Guass[i,i];        }       return x;    }//返回值是函数的系数例如：y=a0+a1*x 返回值则为a0 a1例如：y=a0+a1*x+a2*x*x 返回值则为a0 a1 a2