1_63by0.Sams.Teach.Yourself.Visual.C.NET.in.21

根据DFT的基二分解方法，可以发现在第L（L表示从左到右的运算级数，L＝1，2，3…M）级中，每个蝶形的两个输入数据相距B=2^(L-1)个点，同一旋转因子对应着间隔为2^L点的2^(M-L)个蝶形。从输入端开始，逐级进行，共进行M级运算。在进行L级运算时，依次求出个2^(L-1)不同的旋转因子，每求出一个旋转因子，就计算完它对应的所有的2^(M-L)个蝶形。因此我们可以用三重循环程序实现FFT变换。同一级中，每个蝶形的两个输入数据只对本蝶形有用，而且每个蝶形的输入、输出数据节点又同在一条水平线上，所以输出数据可以立即存入原输入数据所占用的存储单元。这种方法可称为原址计算，可节省大量的存储单元。附件包含算法流程图和源程序。(err)

MATLAB (matrix laboratory) is a numerical computing environment and fourth-generation programming language. Developed by MathWorks, MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages, including C, C++, Java, and Fortran.(MATLAB是MATrix LABoratory的缩写，是一款由美国MathWorks公司出品的商业数学软件。MATLAB是一种用于算法开发、数据可视化、数据分析以及数值计算的高级技术计算语言和交互式环境。除了矩阵运算、绘制函数/数据图像等常用功能外，MATLAB还可以用来创建用户界面及与调用其它语言（包括C，C++和FORTRAN）编写的程序。)

说明：  经典教材，美国人普艾克编著，非常实用的数字信号处理书(Classic textbook, edited by American Pu Yike, very practical book of digital signal processing)

说明：  支持向量机的C++源代码包，用机器学习的方法处理优化问题，可以作为matlab的工具箱。(C++ code for proceeding SVM problems！)

最近从书上看到的非线性解题法的一个程序，共享下(Recently from the book to see non-linear problem-solving method of a program to share the)

matlab讲义是初学者的必备的学习资料，简单易学(Matlab overhead is required for beginners learning, easy)

梯度下降法是最早最简单，也是最为常用的最优化方法。梯度下降法实现简单，当目标函数是凸函数时，梯度下降法的解是全局解。一般情况下，其解不保证是全局最优解，梯度下降法的速度也未必是最快的。梯度下降法的优化思想是用当前位置负梯度方向作为搜索方向，因为该方向为当前位置的最快下降方向，所以也被称为是”最速下降法“。最速下降法越接近目标值，步长越小，前进越慢。(The gradient descent method is the earliest and most simple and most commonly used optimization method. The gradient descent method is simple to realize. When the objective function is a convex function, the solution of the gradient descent method is a global solution. In general, the solution is not guaranteed to be the global optimal solution, and the gradient descent method is not necessarily the fastest. The optimization idea of gradient descent method is to use the current position negative gradient direction as the search direction, because the direction is the fastest descending direction of the current position, so it is also called the steepest descent method. The faster the slowest descent approach is closer to the target, the smaller the step, the slower the progress.)

问题描述： 哥德巴赫猜想：任何大偶数均可表示为2 个素数之和。(Problem Description: Goldbach conjecture: any large even number can be expressed as two Primes.)

MULTIPHYSICS 中与MATLAB的友好链接。可从MATLAB中直接导入(MULTIPHYSICS in the friendly links and MATLAB. Can be imported directly from the MATLAB)

VC++与Matlab混合编程时，所需的lib库文件压缩包(VC++ and Matlab mix program，need liblibrary rar)