user-subroutines-l4-usdfld

说明：  Matlab求解微分方程组，几种经典算法(MATLAB Solves Differential Equations, Several Classical Algorithms)

贪婪算法，可以用于资源分配等许多数学问题和工程问题中(Greedy algorithm)

基于凸优化算法的矩阵填充稀疏矩阵理论的Matlab实现。(Based on convex optimization algorithm of matrix fill sparse matrix theory Matlab achieve.)

该程序用fortran90编写，时域有限差分（FDTD)中的分裂场方法。解决了斜入射情况下周期结构的电磁散射问题。(FORTRAN90 prepared with the program, finite difference time domain (FDTD) method of splitting the market. Solved the case of oblique incidence of electromagnetic scattering from periodic structure issues.)

根据经度纬度时间，计算太阳的方向角，matlab源码，附有详细的文档注释。(According to longitude latitude time, calculating the direction of the sun angle, matlab source, with detailed documentation of the Notes.)

用matlab所编的关于用传输矩阵法计算光子晶体的反射率,文件中将程序写在word文档中,并附带有在matlab下画的图,感觉很有用(using Matlab as in the use of the transfer matrix method photonic crystal reflectivity, Lieutenant General procedures documents written in word document, together with the painting under Matlab plans, feeling useful)

matlab语言写的计算八木天线的程序，可以改变单元的数量，给出各个阵子的电流分布和方向图 (matlab language computing Yagi antenna program, you can change the number of units each time around given the current distribution and orientation map)

FFT快速傅里叶变换 采用基4 fft实现的c语言版(FFT Fast Fourier Transform implemented using the base 4 fft c language version)

平面应力、平面应变有限元数值计算,适合于有限元编程入门(plane stress and plane strain for numerical calcualtion)

用三元组表为结构，实现稀疏矩阵的加法并输出。(Achieve sparse matrix addition)