fitqr

说明：  球形粒子Mie 散射用Matlab编写的Mie theory计算程序。在光子学中运用广泛，使用非常方便(Mie scattering of spherical particles prepared by using Matlab program Mie theory. In the use of photonics in a wide range of very convenient to use)

计算离散傅里叶变换的一种快速算法，简称FFT。快速傅里叶变换是1965年由J.W.库利和T.W.图基提出的。采用这种算法能使计算机计算离散傅里叶变换所需要的乘法次数大为减少，特别是被变换的抽样点数N越多，FFT算法计算量的节省就越显著。(A computing discrete Fourier transform fast algorithm, referred to as FFT. Fast Fourier Transform in 1965 by the JW Cooley and TW Tuji Ti out. Using this algorithm enables a computer to calculate the number of multiplications needed for the discrete Fourier transform greatly reduced, especially sampling points N is transformed more and save FFT algorithm to calculate the amount of the more remarkable.)

实现了粒子滤波算法代码，供大家参考学习。(Particle filter algorithm to achieve the code for your reference study.)

实现矿井采空区的孔隙率和粘性阻力系数，主要用于采空区瓦斯抽采(The porosity and viscosity resistance coefficient of mine goaf can be achieved.)

说明：  利用不动点迭代和牛顿迭代求解非线性方程解的理论(Theory of Solving Nonlinear Equations by Fixed Point Iteration and Newton Iteration)

是学习PCA特征提取的很好的学习资料，能量熵的计算，对于初学matlab的同学会有帮助。( Is a good learning materials to learn PCA feature extraction, Energy entropy calculation, Matlab for beginner students will help.)

说明：  通过模型决定系数完成支持向量机参数优化，并建立基于大数据的支持向量机模型实现回归拟合(The parameters of SVM are optimized by the coefficient determined by the model, and the regression fitting is realized by the support vector machine model based on big data)

Delphi实现最小二乘法，进行多点拟合，目前支持4点拟合(Delphi realizes the least square method and multi-point fitting. At present, it supports four-point fitting.)

begining of UMAT in abaqus

二维脊形光波导的FDTD仿真，能轻易修改波导尺寸和波导介质，，对硅等高折射率的波导求解正确(fdtd simulation of optical waveguide)