brook的专栏

一、关于netgen在优快云有非常好的介绍1.netgen.5.0.0下载地址与Windows下编译方法（https://blog.youkuaiyun.com/zhouschina/article/details/9050373?utm_medium=distribute.pc_relevant_t0.none-task-blog-OPENSEARCH-1.add_param_isCf&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog

1.python程序from netgen.geom2d import * #SplineGeometry()在这个库里面from ngsolve import * #Draw()在这个库里面geo = SplineGeometry() #spline线#四个关键点p1 = geo.AppendPoint (0,0)p2 = geo.AppendPoint (1,0)p3 = geo.AppendPoint (1,1)p4 = geo.AppendPoint (0,1)#两直一曲，三条

一.下载和安装netgen网址https://ngsolve.org/downloads，目前最新的版本为NGSolve-6.2.2008-win64.msi。按默认设置安装即可，不需要更改任何选项。二.下载和安装python与nengen6.2匹配的python版本为3.7。网址https://www.python.org/downloads/windows/。下载DownloadWindows x86-64 executable installer。注意select the option..

1. 求大型矩阵的特征值和特征向量，对称矩阵或非对称矩阵都有可以求，实数阵或复数阵都可以解，因Arnoldi Method（阿诺德）而得名。ARPACK is a collection of Fortran77 subroutines designed to solve large scale eigenvalue problems.有两个关键词，一是Implicitly Restarte