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 二元多次线性方程拟合曲线(Fitting two yuan multiple curves with least square method X coordinate set of known points Y coordinate set of known points The highest degree of the equation of the number of known points