fft

基于多点的快速傅立叶变换算法C++开发环境(based on multi-point fast Fourier transform algorithm C Development Environment)

说明：  积分公式(用锲比雪夫多项式构造积分点公式)(integral formula(using the Cheb. polynomial integral point) )

读入红细胞图片，通过中值滤波，开运算算，闭运算，和贴标签等方法获得细胞个数 (Read into the red blood cell picture, opening operation count median filtering, and closing operation, and the labeling methods such as cell number)

说明：  用LBM代码编写的由于温差而产生的自然对流小程序(As with the LBM code written in natural convection resulting from temperature applet)

计算波导中四波混频效率，考虑线性损耗、自由载流子吸收损耗、双光子吸收损耗(FWM efficiency in silicon waveguide)

用流体计算李指数的。是用excel中的vba做的小程序。(calculated the lyapunov exponent)

首先根据高斯白噪声频率充满整个频带的特性，通过双树复小波包变换对高斯白噪声进行分解，利用频带能量泄漏的定量分析方法，验证了双树复小波包变换具有较低的频带能量泄漏特性；其次利用双树复小波包变换逐层分解信号，对每层分解所得分量求其FFT谱的峭度，得到基于双树复小波包变换的谱峭度图，根据图中峭度最大的原则，可以自动准确的选择信号分解最佳层数和最佳分量；最后将基于双树复小波包变换的谱峭度图的故障诊断方法应用于实际工程中，对齿轮故障振动信号进行分析，选择最佳分解层数和分量后利用希尔伯特包络解调，有效准确地提取了故障特征信息，验证了方法的可行性和有效性(The parameters of a filter were determined by experience, and that has a great influence on the results of signal processing. The discrete wavelet packet transform has a larger energy leakage of frequency band, which obviously affected the results of the envelope demodulation. It is necessary to have a method with a lower energy leakage of the frequency band before envelope demodulation. The dual tree complex wavelet packet transform (DT-CWPT) was a new signal processing method that had many good qualities. Because the energy leakage of the frequency band was smaller when the signal was decomposed by a dual tree complex wavelet packet transform, the dual tree complex wavelet packet transform was used to extract the fault feature information in the field of fault diagnosis. In this paper, first, according to the characteristics of Gaussian white noise, whose frequency was full of the whole frequency band, Gaussian white noise was decomposed by a dual-tree complex wavel)

说明：  计算两组向量之间的旋转矩阵。输入参数为在两个不同坐标系中的同名向量（模为1），返回参数是一个3X3的旋转矩阵。(The function of RM realize the rotation between two sets of vectors, whose magnitude are 1, defined in two different refrence frames. Input parameters are two sets of vectors r and b, return value is a rotaton matrix.)

经典的三维有限元网格生成程序全套源代码及配套的前处理、后处理程序。用C++和Fortran开发。同时配有Manual使用手册。(a three-dimensional finite element mesh generator with built-in pre- and post-processing facilities, source codes are compiled by C++ and Fortran language, with manual.)

该程序是正定矩阵的Cholesky分解实例，Cholesky是矩阵分解常用的方法(The procedure is the Cholesky decomposition of positive definite matrix example, Cholesky matrix decomposition is a commonly used method)