interpolare

说明：  matlab基础知识，PPT文件，内部资料简单，对于深入学习的人不是很合适(matlab basic knowledge, PPT files, internal information is simple, the depth of learning are not very suitable)

using LSB method for putting ke text file in an image

PROGRAM FOR UR USE

图像压缩的功能，提取图像信息以及最后的图像增强(image enhancement)

这是一个频谱分析的matlab程序，通过FFT变换,获得采样数据基本信息，时域图，频域图。(This is a spectrum analysis matlab program, through FFT transformation, get the basic information of sampling data, time-domain map, frequency-domain map.)

cwp组织开发的matlab代码，用以研究各向异性介质中的地震传播规律，计算反射系数，速度，密度等(Contents of this directory are Matlab packages to perform the following tasks. NOLIN_Rp, Petr Jilek, (NOnLinear Inversion of Rp reflection coefficients) package REFLCOEF, Petr Jilek, displacement reflection coefficients at a planar interface and reflectivity modeling for P incident on anisotropic media (up to monoclinic) having a horizontal symmetry plane. LIN_Rp, Petr Jilek, joint linear inversion of approximate PP and PS wave reflection coefficients: current version designed for anisotropic media including isotropic, HTI, VTI, and orthorhombic symmetry. Multi_Comp_Stack_Vel_Tomo, Vladimir Grechka and Andres Pech, joint tomographic inversion of the NMO ellipses, reflection slopes, and zero-offset traveltimes of PP- and SS-waves. )

关于matlab 和C 混合编程的一个文档材料，推荐看一下。(a file about the programme of matlab and C.)

采用EM，期望最大方法，估计QPSK调制方式下的信噪比(Using EM, expectation maximization method to estimate the signal to noise ratio under QPSK modulation)

PCA的步骤： 1 先将数据中心化； 2 求得的协方差矩阵； 3 求出协方差矩阵的特征值与特征向量； 4 将特征值与特征向量进行排序； 5 根据要降维的维数d’,求得要降维的投影方向； 6 求出降维后的数据； (PCA steps: 1 of the first data center 2 covariance matrix obtained 3 obtained covariance matrix eigenvalues and eigenvectors 4 eigenvalues and eigenvectors will be sorted 5 according to the dimension of dimension reduction d ' , seek to reduce the dimension projection direction 6, the data obtained after the dimensionality reduction )

欧拉角表示法具有简便、几何意义明显等优点，同时姿态敏感器可以直接测出这些参数，能较方便地求解用这些姿态参数描述的姿态动力学方程。但采用欧拉角的姿态描述方法存在奇点问题，且需多次三角运算。而采用四元数表示方法则可以避免这些问题。(conversion between euler angle and quaternion method)