photonic_band_structure

己知一些离散的点，使用matlab利用最小二乘法拟合(Had a number of discrete points, with linear least squares fitting)

ABAQUS中用户材料子程序UMAT的开发主要解决两方面的问题：本构模型的建立和积分算法的选择。 本文主要研究非线性材料的UMAT实现方法，并重点研究其迭代算法部分，目前，用户材料子程序UMAT的迭代算法主要是常刚度法，常刚度法的优点在于算法原理较简单，程序编写较方便，缺点是当遇到复杂非线性材料时，其迭代次数较多，收敛速度也较慢，在这个情况下，本文采取的是一种迭代次数较少且收敛速度较快的切线刚度法，具体就是采用FORTRAN语言编制了基于Von-Mises模型的接口程序,并采用切线刚度算法，通过与ABAQUS自带本构关系计算的结果相比较，验证其正确性。(This paper studies the user subroutine UMAT of ABAQUS development methods, the use of FORTRAN language isotropic hardening material model of the interface program, studied the effects of such material is extremely elastic-plastic constitutive relation method. This article UMAT tightly around the secondary development of technology, the first principle of its interface detail, and then for the theory of nonlinear finite element incremental stiffness of the regular tangent stiffness method and the theory of algorithms to do an in-depth analysis of deduced a regular tangent stiffness and rigidity of the law of the specific expression of algorithm theory, and then the preparation of the two algorithms, respectively, of the UMAT program, and finally the establishment of a specific model checking, bringing with ABAQUS elasto-plastic constitutive relation of the calculated results compared to verify the correctness of the two.)

这是地球物理学中声波波动方程正演程序，非常有用(this is a program about finite difference)

可以用最小二乘法来提取趋势项。在MATLAB中可利用它的函数来计算(Least squares method can be used to extract the trend items. It can be used in MATLAB to calculate the function)

课程设计：编写连续函数最佳平方逼近的算法程序（以函数形式）。并用此程序进行数值实验，并提交相应的实验结果数据与报告。 内附详细的课程设计报告与源代码()

计算多边形(凸凹)面积。 欢迎批评指正(Calculating polygon (convex and concave) area. Welcome criticism)

内含心电信号数据及运用MATLAB写的源代码，有井曲线作为输入可计算其地震波的衰减,Pisarenko谐波分解算法。( ECG data and includes source code written in MATLAB, There is a well attenuation curve as input to calculate its seismic waves, Pisarenko harmonic decomposition algorithm.)

求二元一次方程组的解,简便算法的过程及计算(Solving linear equations group，Process and simple calculation algorithm)

matpower工具箱中的算例，基于ieee118的最优潮流计算，包含源代码(matpower toolbox example, calculated based on the ieee118 the OPF contains the source code)

求解最短路算法，，， 赋路径初值 更新 显示迭代步数 显示每步迭代后(solve the lest distance)