Homotopy

1. 牛顿迭代法 function [x,i]=newtonmethod(x0,f,ep,Nmax) 牛顿法求非线性方程根 x0是输入初始值, f是输入函数, 精度要求ep, Nmax为最大迭代次数 x是输出迭代序列,i是迭代次数 2. 二分法 function [x,k]=bisection(a,b,f,ep) 二分法解非线性方程 输入区间[a,b],函数f和误差ep, Nmax为最大二分次数 x为输出近似根, k为二分次数 ( Newton s law and the dichotomy)

TDMA solver for tridiagonal matrix

介绍线性算子的基本概念的文章,这是书里面的一个章节(Foundation of linear operator theory)

分别采用GMM和KDE对Iris数据集进行密度建模，并进行对比。通过EM算法来确定GMM参数，通过交叉验证来确定K值(GMM and KDE respectively Iris data set of density modeling, and compared. GMM by EM algorithm to determine the parameters of K determined by the value of cross-validation)

fortran数值计算方面的一本好书，计算机数值算法的圣经。(Numerical Recipes in Fortran 77 The Art of Scientific Computing Second Edition Volume 1 of Fortran Numerical Recipes)

埃特金加速法,一个数值分析中的算法,大家先看看哦(Aitken acceleration method, a numerical analysis of the algorithm, we look at the flash open her cloak)

几何绕射理论，是高频解决电磁场问题的方法，本书很具有代表性(GTD is a high-frequency electromagnetic fields to solve the problem, this book is a representative)

说明：  包括我自己写的一些数值分析用到的函数 包括矩阵的LU分解的两种方法, Cholesky分解, 以及线性方程组的迭代解法中的雅克比, 高斯-赛德尔以及线性松弛法的函数(Including myself, used to write some of the numerical analysis functions, including matrix LU decomposition of two methods, Cholesky decomposition, and iterative solution of linear equations in the Jacobi, Gauss- Seidel and linear relaxation method function)

fft小程序：可用于分析离散值采集数据的谐波含有率，谐波角度等(fft小程序：可用于分析离散值采集数据的谐波含有率，谐波角度等 FFT small program: can be used to analyze the discrete value of the data acquisition of the harmonic content, harmonic angle, etc. )

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.)