J2000toWGS84

实现了测井数据的fft变化分析，可以用于查看测井数据的频谱特征(Realize the logging of data changes fft analysis, can be used to view the logging data of spectrum characteristics of)

说明：  该程序用有限元方法来处理标量亥姆赫兹方程，其实例是脊形介质波导中的光波。(The functino of the code is to slove Helmholtz equation by using finite element method (FEM). The example is an optical waveguide.)

适用于大型稀疏矩阵 矩阵转置 c语言 来自于有限元方法编程(From the finite element method suitable for large-scale sparse matrix matrix transpose c language programming)

牛顿插值法进行多项式逼近，matlab编译成功，直接可用(Newton interpolation polynomial approximation method, matlab compiled successfully, directly available)

计算动力学研究，应力波引起的裂纹扩展问题，供大家学习(Kinetics calculations, crack propagation problems caused by stress wave for everyone to learn)

程序计算在声速梯度下水中声线的传播并计算声线的长度(Program calculates the velocity gradient in the water line of acoustic sound propagation and calculate the length of the line)

电力系统继电保护中经常应用的滤波算法，基于电力系统电流信号的傅里叶变换。程序给出了算法的仿真实现。(Power system, Filtering Algorithm, Fourier Transform, Simulation in matlab)

QR分解法是目前求一般矩阵全部特征值的最有效并广泛应用的方法，一般矩阵先经过正交相似变化成为Hessenberg矩阵，然后再应用QR方法求特征值和特征向量。它是将矩阵分解成一个正规正交矩阵Q与上三角形矩阵R，所以称为QR分解法,(QR decomposition )

对大规模的矩阵做高斯消元，适合大规模矩阵求逆！！！！！(Done on a large scale matrix Gaussian elimination, suitable for large-scale matrix inversion! ! ! ! !)

自己编写的变步长龙格库塔方法解强非线性微分方程(their preparation variable step Changlong lattice-Kutta method to solve nonlinear differential equations)