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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 )

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)

非常实用的时域仿真法暂态分析工具，利用牛顿法求解系统的微分方程组和代数方程组，得到转子摇摆曲线，判断暂态是否稳定(Very useful time-domain simulation tool for transient analysis method, using Newton method for solving systems of differential equations and algebraic equations, the rotor swing curves, to determine the stability of transient)

说明：  利用该方程组求解一般的线性方程组，别且符合数学求解原理(Using the equations of linear equations in general, do not and in accordance with principles of mathematics to solve)

计算流体力学软件FLUENT计算空气龄的udf文件(FLUENT CFD software udf file to calculate the air age )

埃特金加速法 中国矿业大学理学院 计算方法实验5,还可以的(Aitken acceleration method China mining university faculty of science calculation method for the experiment 5, you can also)

电磁场与微波技术下的射线追踪技术。应用c语言编程(Electromagnetic Field and Microwave Technology under the ray tracing technique. Application c programming language)

这是用C++编写的 用高斯方法求解方程的方法 我想对与计算机数学的同学来说 可能会有用(It is written with C++ method for solving equations using Gaussian approach I want to mathematics and computer may be useful for the students)

用C++编写的一维和二维快速傅里叶变换程序(Prepared with C++ one-dimensional and two-dimensional fast Fourier transform procedure)

汽车油耗计算（C实现）对于家用经济型小轿车来说，统计油耗是经常做的一件事。本题目要求根据汽油单价、每次加油所用钱数，以及该次加的油所跑里程数计算出该车的百公里油耗，并进行保存，根据需要给出统计数据。(Vehicle fuel consumption calculation (C implementation) for the household economy cars, the fuel consumption statistics is often one of the things. The questions asked based on gasoline price, amount of money each fuel used, and the second oil added to calculate the mileage run car 100 km fuel consumption, and save, according to the need to give statistics.)