从三次样条曲线到二维点的拟合
Fitting cubic spline curve to 2d points
简介：该代码根据文献"Fitting B-spline Curves to Point Clouds by Curvature-Based Squared Distance Minimization"撰写。
Introduction
This is an implementation of paper "Fitting B-spline Curves to Point Clouds by Curvature-Based Squared Distance Minimization".
Link to the paper: http://www.geometrie.tuwien.ac.at/ig/sn/2006/wpl_curves_06/wpl_curves_06.html
输入是一组二维点，输出是一条闭合三次样条曲线的控制点。
The input is a set of 2d points, the output are control points of a close cubic spline curve.
输入文件：包含n行的文件，每行代表一个x y位置的点。
Input file: a file that contains n rows and each row reprents a point with x y positions.
输出文件：包含输出曲线控制点的文件以及包含输出文件采样点的文件。
Output files: a file with the control points of the output curve; and a file with sampling points of the output file.