algorithms(CPP)

FFT快速傅里叶变换，用于数字信号处理，大大提高了运行速度，节省内存开销。C语言实现(FFT fast Fourier transform for digital signal processing, greatly improving the speed and save memory overhead. C language)

样条插值算法的matlab代码，包括一次样条插值，二次样条插值和三次样条插值，可根据需要选择(Spline interpolation algorithm matlab code, including a spline interpolation, quadratic spline interpolation and cubic spline interpolation, can be selected)

本书用c语言编写了科研和工程中最常用的166个算法,这些算法包括复数 运算、... 4.3.1 【算法23】求一般复矩阵的逆 4.3.2 【算法24】求对称正定矩阵的(good study)

基于Wegstein方法的求解方程的C++程序。(Wegstein-based method for solving equations C++ program.)

C++编写“三维粱单元有限元计算内核”，对杆系有限元的理论和C++的理解有了很大提高(C++ written " three-dimensional beam finite element kernel module" , and on finite element theory and the understanding of C++ has been greatly improved)

利用PHOTOSHOP软件可以量测出左右像片各控制点的像素坐标，通过公式可以计算出其像点坐标。再根据给定的控制点的空间坐标，利用直线线性变换解法计算出11个DLT参数即l的系数值以及内方位元素然后解算出外方位元素。另外一种方式是用单像空间后方交会的公式计算出外方位元素。利用单像空间后方交会的来结算影像的外方位元素的基本思想是：以单幅影像为基础，从该影像所覆盖地面范围内若干控制点的已知地面坐标和相应点的像坐标量测值出发，根据共线条件方程，解求该影像在航空摄影时刻的外方位元素。首先建立单文档的程序，建立一个对话框类，在这个类中进行像素坐标、控制点坐标文件的打开与读取，然后利用DLT公式进行外方位元素的解算。 数据检核部分用前方交会算法来进行，首先根据ID找到左右片的像点的同名点，然后计算变换矩阵及系数，根据给定的内方位元素，利用公式解算出像点的控制点坐标，然后和给定的控制点坐标相比较即可进行精度评定。 (PHOTOSHOP software can be measured using a photo of the control points around the pixel coordinates can be calculated by the formula sit out the image point Standard. According to the given coordinates of control points, the use of straight-line method to calculate the linear transformation of 11 DLT parameters that the coefficient l Value and calculate the orientation elements of exterior orientation elements and solutions. Another way is to use a single formula as the calculation of space resection Orientation elements out. Use as space resection alone to settle the image exterior orientation is the basic idea: to single video As the basis of images from the ground covered by a number of control points within the known ground coordinates and image coordinates of corresponding points in the measured values , The realities of collinearity equation, find the image in the time of aerial photography exterior orientation elements. First, the process to establish a single document)

之前找不到合适精度的log2x函数的定点化源码，经过实现并验证后，发上来大家一起学习(fixed version for log2x)

求解一维热传导方程，格式包括FTCS、BTCS、CNCS三种差分格式(solve one dimension heat transfer equation. )

多物理场耦合软件采用有限元方法模拟表面等离子体激元，适合入门学习者(Multi-physics coupling software using the finite element method to simulate the surface plasmon, suitable for entry-learners)

平面波展开法计算二维三组元周期结构的带隙特性。(Plane wave expansion method for calculation of two dimensional three groups yuan cycle structure of the band gap characteristic)