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说明：  基于CORDIC算法计算反正切函数。输入横坐标纵坐标及迭代次数，输出角度及弧度值；附CORDIC英文文档说明(atan function based in CORDIC algorithm)

idl环境下运行，计算两幅图像的交叉相关系数，用于变化检测方面的研究(idl environment to run the calculation two images of cross-correlation coefficient for change detection studies)

非线性算法合集，包括牛顿拉夫逊法，Broyden拟牛顿法，弧长法，割线法。每种算法都包含有线性搜索迭代改进。(Nonlinear algorithm collection, including Newton Raphson, Broyden quasi-Newton method, arc-length method, secant method. Each contains a linear search algorithms for iterative improvement.)

Dsimplex.m 对偶单纯形法求解线性规划问题(Dual simplex method for solving linear programming problems)

常用的matlab代码，非线性方程组求解，基本可以满足大学和研究生常用代码(Common Mathematical Codes)

用一个N点复序列的FFT同时计算两个N点实序列离散傅里叶变换(With an N-point complex sequence of N-point FFT calculate two real sequences discrete Fourier transform)

二维粘弹性介质中波的传播的解析形式。应用Carcione等在1988年发表的《WAVE PROPAGATION SIMULATION IN A LINEAR VISCOELASTIC MEDIUM》一文中的方法，更加详细的介绍见英文描述。该代码对于做波场模拟的同学有很好的参考价值。( MATLABScript for obtaning the analytical solution for 2D wave propagation in a viscoelastic medium, based on the Appendix B of paper of Carcione et al. (1988)(1), corrected in (2). The source used is a Ricker wavelet in the y velocity component. A figure of the source temporal function and its inverse Fourier transform are provided to verify the good working of the method. Also works for elastic variables by substituting the values of vp and vs by real constant ones (vp_0 & vs_0). Attenuation is implemented by GMB-EK rheology presented in (4) and thoroughfully explained in (3). In order to make a proper comparison with numerical data it is recommended to either use the same rheology in both the numerical and the analytical. It is also possible to get an almost constant Q value by increasing a lot the number of mechanisms used in both the numerical and the analytical solutions, thus minimizing the effects of the Q fitting in the comparison.)

说明：  重力异常正演代码，请好好使用它。帮助学习。。。。(Gravity anomaly forward code, please use it well. Help learn)

point cloud 点云配准计算，通过选择几组匹配的点云数据对对点云数据进行配准处理(point cloud point cloud registration computing, by selecting a set of match point cloud data point cloud data registration process)

采用相互垂直的两个振子构成圆极化天线的FDTD程序．可以计算其圆极化波瓣宽度等天线指标 (perpendicular to each other using the two oscillator constitute a circularly polarized antenna FDTD procedures. Can calculate its lobed circular polarization antennas width indicators)