用牛顿法解非线性方程组

基于时间序列法的超短期电力负荷预测 利用时间序列法进行数学建模(Mathematical modeling based on very short-term power load time series forecasting using time series method)

fdtd的2d算法，pml边界条件，二维TE波(fdtd the 2d algorithm, pml boundary conditions, 2D TE wave)

对平面上给定的多点进行多项式曲线的拟合，可设置拟合多项式的次数(Given more points on the plane polynomial curve fitting, you can set the number of polynomial fitting)

本程序在matlab中运行。 Generate_SystemMatrix是一个计算OSEM，MLEM迭代图像算法中系统矩阵的函数，其用法Generate_SystemMatrix（pixel），为所要重建图像的大小，一般为64,128,256，pixel也大运算越慢。 里面的diedai-test文件是一个简单的MLEM重建算法，其中要加载SystemMatrix矩阵就是Generate_SystemMatrix(128)的结果，注意如果要运行diedai-test，生成的系统矩阵名要保存为SystemMatrix，否则出错。 testsino是一个正弦图实例，就是MLEM算法中的投影矩阵，机算是数据。(This program is run in matlab. The Generate_SystemMatrix is ​ ​ a calculation of the OSEM, a function of the system matrix MLEM iterative image algorithm, its use Generate_SystemMatrix (pixel) to rebuild the image size, usually 64,128,256, pixel also large computing slower. Inside diedai-test file is a simple MLEM reconstruction algorithm, which load SystemMatrix matrix is ​ ​ the result of Generate_SystemMatrix (128), pay attention to if you want to to run diedai-test, the generated system matrix is ​ ​ saved as SystemMatrix, otherwise an error. testsino instance of a sinogram projection matrix MLEM algorithm, machine be regarded as data.)

用于有限元软件Abaqus分析材料断裂的粘结区模型（CZM）子程序，由著名学者高彦飞编程，具有很高的参考价值。(ABAQUS allows the addition of a variety of user subroutines. We define a user element by UEL. Information of element and nodal displacements can be obtained from ABAQUS, and we update the stiffness matrix and the residual vector following the cohesive zone law. More coding details can be found in ABAQUS manual.)

本程序实现利用高斯全选主元法解矩阵方程，即高斯-约旦法解方程(This program Gaussian Select the primary element method for solving matrix equation, that Gauss- Jordan method of solving equations)

线性方程组的计算，采用的是高斯消元法来实现的。只有主要的算法代码，没有写主函数(Calculation of linear equations using the Gauss elimination method to achieve. Only the main algorithm code, did not write the main function)

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)

偏微分方程数值解上机实习 运用古典显式差分格式求解二维扩散方程的初边值问题 运用P-R差分格式求解二维扩散方程的初边值问题

早期的圆柱绕流程序，用fortran语言编写，用来了解早期绕流流动的发展(flow around the cylinder)