single4

code for ferequency responce

This tutorial is designed to give the reader an understanding of Principal Components Analysis (PCA). PCA is a useful statistical technique that has found application in fields such as face recognition and image compression, and is a common technique for finding patterns in data of high dimension. Before getting to a description of PCA, this tutorial first introduces mathematical concepts that will be used in PCA. It covers standard deviation, covariance, eigenvectors and eigenvalues. This background knowledge is meant to make the PCA section very straightforward, but can be skipped if the concepts are already familiar.

不错的GM_EM代码。用于聚类分析等方面。( GM_EM- fit a Gaussian mixture model to N points located in n-dimensional space. Note: This function requires the Statistical Toolbox and, if you wish to plot (for k = 2), the function error_ellipse Elementary usage: GM_EM(X,k)- fit a GMM to X, where X is N x n and k is the number of clusters. Algorithm follows steps outlined in Bishop (2009) Pattern Recognition and Machine Learning , Chapter 9. Additional inputs: bn_noise- allow for uniform background noise term ( T or F , default T ). If T , relevant classification uses the (k+1)th cluster reps- number of repetitions with different initial conditions (default = 10). Note: only the best fit (in a likelihood sense) is returned. max_iters- maximum iteration number for EM algorithm (default = 100) tol- tolerance value (default = 0.01) Outputs idx- classification/labelling of data in X mu- GM centres)

最小二乘法（又称最小平方法）是一种数学优化技术。它通过最小化误差的平方和寻找数据的最佳函数匹配。利用最小二乘法可以简便地求得未知的数据，并使得这些求得的数据与实际数据之间误差的平方和为最小。最小二乘法还可用于曲线拟合。其他一些优化问题也可通过最小化能量或最大化熵用最小二乘法来表达。 (Least-squares method (also known as least squares) is a mathematical optimization techniques. It does this by minimizing the square error of the data and find the best match function. The least square method can easily obtain the unknown data, and makes these data and the actual data obtained between the square and the smallest error. Least-squares curve fitting method can also be used. Other optimization problems can be maximized by minimizing the energy or entropy of the least square method to express. )

ista算法，用于最优化求解,迭代收敛，实用小程序(ista algorithm, for the most optimtical problem)

matlab code for seismic Migration

第七章 IIR滤波器设计 数字滤波器：将输入序列通过一定运算，变换成输出序列的离散时间系统（数字网络）。 (Chapter 7 IIR filter design digital filters: input sequence is converted into the output sequence of discrete time system (Digital Network) through certain operations.)

【实例简介】LVQ神经网络的分类——乳腺肿瘤诊断

searching nearest neighbor in a network

基于差分进化的粒子群优化算法，（全局最优粒子群优化算法）(Based on differential evolution particle swarm optimization, (global optimization PSO))