实现对离散数据的最小二乘法拟合，得到多项式表达式-Least squares fit of the discrete data obtained polynomial expression

使用三次样条插值法，对离散数据进行拟合，并得出各点间表达式-Use the cubic spline interpolation, to fit the discrete data and concluded between the expression

从随机的数据中找出其规律性，给出其近似表达式的问题，在生产实践和科学实验中大量存在，通常利用数据的最小二乘法求得拟合曲线。-From random data to find its regularity, give its approximate expression problems in the production practice and scientific experiments abound, often use the data obtained by least squares

根据所给的点的坐标算出最拟合曲线的公式，并根据原来的x值算出新的y值。并将数据储存到一个data文件-A C++ programme finds the best-fitted straight line to the x and y values, and then writes the original x, y values and the new y values on the line (for each x) to a data file. X: 1.0000 2.0000

最小二乘曲线拟合 输入数据和阶数 输出函数系数-Least-squares curve fitting and order input data output function coefficients