jisuanqi

说明：  Galileo单频定位程序，能基于rinex文件实现高精度定位，供编写时参考(Galileo single-frequency positioning program can achieve high-precision positioning based on RINEX file for reference when writing.)

用mfc实现计算器的基本操作，支持键盘输入，并保留xp风格,可计算平方，幂，时间显示等操作(With mfc achieve the basic operation of the calculator, support for keyboard input, and retain xp style, calculates the square, power, time display and other operations)

解释有限元程序SAP5的原理，结构，算例的一本书籍(The finite element program SAP5 explain the principles, structure, examples)

一个简单的傅立叶带亮度描绘子提取图像的形状特征程序(A simple Fourier descriptor with the brightness of the image shape feature extraction procedures)

利用五点差分格式和Jacobi迭代法，求解精确解和数值解的误差，判断阶数是否正确(Five-point difference scheme and Jacobi iteration method are used to solve the error between exact solution and numerical solution and to judge whether the order is correct or not.)

2维非结构欧拉求解 fortran代码，用于2维流场求解(2D Unstructured Euler code)

根据极限状态方程，计算结构的可靠度和敏感度程序(According to limit state equation, the calculation of structural reliability and sensitivity procedures)

说明：  共轭梯度法（Conjugate Gradient）是介于最速下降法与牛顿法之间的一个方法，它仅需利用一阶导数信息，但克服了最速下降法收敛慢的缺点，又避免了牛顿法需要存储和计算Hesse矩阵并求逆的缺点，共轭梯度法不仅是解决大型线性方程组最有用的方法之一，也是解大型非线性最优化最有效的算法之一。 在各种优化算法中，共轭梯度法是非常重要的一种。其优点是所需存储量小，具有步收敛性，稳定性高，而且不需要任何外来参数。(Conjugate gradient method Gradient) is a method between the steepest descent method and Newton's method. It only uses the first derivative information, but overcomes the disadvantage of slow convergence of steepest descent method, and avoids the disadvantage of storing and calculating Hesse matrix and solving inverse of Newton's method. Conjugate gradient method is not only one of the most useful methods to solve large-scale linear equations, but also the most effective method to solve large-scale nonlinear optimization One of the algorithms of. Among all kinds of optimization algorithms, conjugate gradient method is very important. It has the advantages of small storage, step convergence, high stability and no external parameters.)

说明：  非常详细的umat 雅可比矩阵更新算法的讲解(detailed describetion of the jacobian matrix in abaqus umat)

用DFT 函数计算电压u, 电流i的基波(f1=50 Hz)的有效值和相位; 用FFT函数分别计算电压u和电流i 所包含的直流,基波和谐波的有效值和初相角; 可计算基波(f1=50 Hz)和各次谐波的功率p和功率因数con?.(The effective value and phase of fundamental wave (f1 = 50 Hz) of voltage U and current I are calculated by DFT function. The effective values and initial phase angles of DC, fundamental and harmonic waves contained in voltage U and current I are calculated by FFT function, respectively. The power P and power factor con of fundamental wave (f1 = 50 Hz) and harmonics can be calculated.)