code-hxf

利用SAR卫星在多个时刻的位置和速度信息，计算出任意象元成像时刻卫星的位置，拟合出SAR卫星的轨道模型。(Using SAR satellite in multiple time position and velocity information to calculate as the image element imaging time satellite position, fitting the SAR satellite orbital model.)

说明：  萤火虫算法，一种新型算法。参数设置少，迭代速度快，结果精确。(Firefly algorithm, a new algorithm. Parameter setting small, iterative fast, accurate results.)

％ 奇异值分解 (sigular value decomposition,SVD) 是另一种正交矩阵分解法；SVD是最可靠的分解法， ％ 但是它比QR 分解法要花上近十倍的计算时间。[U,S,V]=svd(A)，其中U和V代表二个相互正交矩阵， ％ 而S代表一对角矩阵。 和QR分解法相同者， 原矩阵A不必为正方矩阵。 ％ 使用SVD分解法的用途是解最小平方误差法和数据压缩。用svd分解法解线性方程组，在Quke2中就用这个来计算图形信息，性能相当的好。在计算线性方程组时，一些不能分解的矩阵或者严重病态矩阵的线性方程都能很好的得到解( Singular value decomposition (sigular value decomposition, SVD) is another orthogonal matrix decomposition method SVD decomposition is the most reliable method, but it takes more than QR decomposition near ten times the computing time. [U, S, V] = svd (A), in which U and V on behalf of two mutually orthogonal matrix, and the S on behalf of a diagonal matrix. And QR decomposition are the same, the original matrix A is no need for the square matrix. The use of SVD decomposition method are used as a solution of least squares error method and data compression. Using SVD decomposition solution of linear equations, in Quke2 on to use this information to calculate the graphics performance quite good. In the calculation of linear equations, some indecomposable matrix or serious pathological matrix of linear equations can be a very good solution)

说明：  利用MATLAB实现了16位快速傅立叶变换，并与自包含函数进行了比较。(The 16-bit Fast Fourier Transform is realized by using MATLAB and compared with the self-contained function.)

自己写的稀疏矩阵类，包括存储、访问以及基本的数学运算，希望大家批评指正！(Sparse matrix classes, including storage, access, and basic mathematical operations, we hope to criticism!)

this document contain some demonstrations in mathematics , it can bee very helpful for beginners

用以计算nscat地球物理模型函数的程序！(This is a program for calculating the nscat geophysical model.)

同时辨识模型阶次及参数算法。用阶次递推算法，结合AIC法——利用赤池信息准则辨识上例的模型阶次和参数。(At the same time identify model order and parameters algorithm. By order recursive algorithm, combined with AIC method- the use of Akaike information criterion to identify the cases of the model order and parameters.)

边界元法，可以求解外声场、内声场,在此基础上可以开发出快速边界元法(boundary element method for acoustic problem)

算法设计与分析之汉诺塔问题介绍与讲解 希望大家有时间看看 (Tower of Hanoi problem description and explanation of the design and analysis of algorithms hope that we have time to look at)