lagrange插值

The only information passed from difeq to solvde is the matrix of derivatives

本书介绍了XFEm在结构件的断裂分析中的应用(this book introduces the application of XFEM in the field of fracture analysis)

FDTD 2 dimension TE modes with UPML Fortran platform

说明：  levenberg-maquardt最小二乘拟合算法(This program do the levenberg-maquardt LS fit.)

PCA算法程序设计步骤： 1、去均值 2、计算协方差矩阵及其特征值和特征向量 3、计算协方差矩阵的特征值大于阈值的个数 4、降序排列特征值 5、去掉较小的特征值 6、去掉较大的特征值(一般没有这一步） 7、合并选择的特征值 8、选择相应的特征值和特征向量 9、计算白化矩阵 10、提取主分量 (PCA algorithm programming steps: 1 to mean 2, calculation of covariance matrix and its eigenvalues and eigenvectors 3, the calculation of covariance matrix eigenvalues greater than the threshold number of 4, in descending order of eigenvalue 5, remove the smaller eigenvalue 6, remove the larger eigenvalue (usually not this step) 7, the combined choice of eigenvalues 8, select the appropriate eigenvalues and eigenvectors 9, computing whitening matrix 10, principal component extraction)

光子晶体光纤计算中相对抽运频率和四波混频效率的关系，有MATLAB程序和图形。对研究光子晶体光纤有很大的帮助。(Calculation of photonic crystal fiber pumped in the relative frequency and four-wave mixing efficiency of the relationship between the procedures and have MATLAB graphics. The study of photonic crystal fiber has a great help.)

浸入边界法（Immersed Boundary Method）的一个示例程序。包括说明文档。(A code using the IBM (Immersed Boundary Method ) . And the help documention is included .)

欧拉法解微分方程方程组，对于变成基础薄弱的人，易于理解，相信会有用处(Euler method for solving differential equations, to become a person, the weak foundation is easy to understand, I believe there will be.)

用于模拟混凝土单元的弹塑性模型，并有损伤变量，在ABAQUS中umat中输入弹性模量，泊松比与屈服应力即可。(The elastic-plastic model for the simulation of concrete unit, and the damage variable in the ABAQUS umat enter the elastic modulus, Poisson' s ratio and yield stress can be.)

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)