python-Machine-learning-master

windows计时器工具，能够精确到毫(0.001)，说明文档请用office2010打开。(windows timer tools, technology is accurate to the mm (0.001), documentation office2010 open.)

利用预估矫正方法解分数阶常微分方程，该方法适用于线性和非线性分数阶常微分方程(using PECE method to solve fractional ordinary differential equation)

vc++实现的矩阵运算方面得代码，很不错的，内容绝对好吃(matrix operations, code vc++ achieve very good, the content is absolutely delicious)

说明：  最小二乘法寻找最佳函数匹配，用以数值计算，优化曲线(The least square method is used to find the best function matching for numerical calculation and curve optimization.)

自己写了一个二维Euler方程的间断有限元程序 上次发了一个三角形单元的程序 因为不是曲边单元 所以在圆柱后面容易形成涡 现在把程序改为曲边四边形单元了 没有涡出现 单元是8节点四边形单元 节点编号顺序是 1 5 2 6 3 7 4 8 也就是四个角点依次 是1 2 3 4 然后是边的中点编号 5 6 7 8. 时间推进采用 Runge-Kutta 方法 数值通量采用全局Lax-Friedrichs通量 仍然不能捕捉激波 因为没有做重构或者加人工粘性 等这个做出来了 再发一次。 程序没有进行优化 比如说内存的消耗没有优化 比如直边单元的边界积分仍然采 用了曲边的积分方法 增加了计算量 比如面积分、线积分都是采用的是Gauss- Legendre-Lobatto积分 积分精度会比一般的Gauss-Legendre积分精度低一阶 等 等问题。 二维的 纯属交流性质 就没有考虑这些问题 ^_^ 如果物面全部是直边 那么只要改变一个参数N 就可以获得不同的计算精度 且具 有谱精度 因为单元的节点是Gauss-Legendre-Lobatto积分点。 其实就是谱元法 （物面是曲边的情况我不清楚是不是也可以通过提高基函数的阶数 也就是增加N 来提高计算精度）(Wrote a two-dimensional Euler equations with discontinuous finite element program Last made ​ ​ a triangular element of the program, not curved edge unit is so easy to form a vortex in the cylinder behind the Program to curved edge quadrilateral element vortices appear Unit is the order of 8-node quadrilateral element node number is 15,263,748 which is the four corners of the points in turn Is 1234 and then the side of the midpoint of the number 5678. Time promote the use of Runge-Kutta method Numerical flux of the overall situation of Lax-Friedrichs, flux Still can not capture the shock wave did not do the reconstruction or artificial viscosity do it Zaifayici. The program is not optimized for example, memory consumption is not optimized such as straight-edge boundary integral of the unit is still mining Integral method to increase the amount of computation such as surface integral with a curved edge, the line integral using the Gauss- The Legendr)

CSharp用于卫星广播星历计算和精密星历计算(Used for satellite radio star calendar calculation and precision star calendar calculation)

2D FDTD TE mode with a plane wave source and a PML abc

QR分解法是目前求一般矩阵全部特征值的最有效并广泛应用的方法，一般矩阵先经过正交相似变化成为Hessenberg矩阵，然后再应用QR方法求特征值和特征向量。它是将矩阵分解成一个正规正交矩阵Q与上三角形矩阵R，所以称为QR分解法,(QR decomposition )

用Matlab程序求解计算物理中使用到的方程，包括：薛定谔方程、傅立叶变换、波函数求解等等(Matlab file is used to describe and solve the equations in the computational physics, including, Schrodinger equation, Fourier transform, wave function solution, etc.)

进行PQ分解，计算电力系统潮流的有效方法，应用广泛(PQ decomposition is an effective method for calculating power flow in power system.)