764

判断点和线段之间的关系，包括点在线段的上，点在线段的延长线，反向延长线，点在线段外四种情况(Judge the relationship between the point and line, including the point on the line, in line at the extension of reverse extension cord, and so on.)

这是一个小型计算器，功能强大，用户输入想要计算的数据，即可自行计算出结果。(This is a program about calculator,and it is very userful.)

说明：  用LBM代码编写的由于温差而产生的自然对流小程序(As with the LBM code written in natural convection resulting from temperature applet)

DFP法求优化问题的C++源代码，经测试，该程序运行正常，得到了预期的结果。(DFP method for the optimization of C++ source code, tested, the program works correctly to get the desired results.)

对于协方差矩阵的一种计算方法，对于地震中的反演约束算法能起到很好的作用。(For a kind of covariance matrix calculation method)

说明：  c++语言求解稀疏矩阵方程组的ICCG法源程序。参考：《工程电磁场数值计算分析与综合》 附录（Fortran90）.(c++ solves sparse matrix equations with the ICCG method.Reference: &quot Analysis and Synthesis of Numerical Electromagnetic Field ,&quot Appendix (Fortran90).)

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)

导线网平差程序，参数约束，通过设定不同的PX达到经典自由网，普通自由网，拟稳平差效果，算例(Wire net adjustment procedures, parameters, constraints, and examples)

共轭梯度法求解凸二次规划，代码由C语言开发，老外编写的程序，很值得一读。(Conjugate gradient method for solving convex quadratic programming, code generated by C language development, foreigners prepared program, it is worth reading.)

APRIORI ALGORITHM IMPLEMENTATION