说明：  用经典的pca k邻域方法估计点云法向量的程序，带有matlab gui，使用matlab 2016b编译运行成功，输入点云最好为列向量的txt文件，gui中内置了点云显示模块以及生成的点云法向量显示，并且可以输出法向量到txt文件中。
(The program of estimating point cloud vector with the classical PCA K neighborhood method, with Matlab GUI, uses MATLAB 2016b to compile and run successfully, the input point cloud is the best column vector TXT file, the point cloud display module and the generated point cloud vector display in GUI are built in Gui, and the normal vector can be output to the txt file.)