util_mod

世界上最好的微积分教材，搞程序的，研究的，数学的都应该了解，这个是James.Stewart的Calculus第七版，英文原版，彩色的，值得珍藏。(The world' s best calculus textbook, engage in programs, research, mathematics should understand that this is James.Stewart seventh edition of Calculus, English original, colorful and worth treasuring.)

说明：  some article about Bayes Thinking

说明：  本程序计算的太阳角有地面点对应的太阳天顶角和太阳方位角，太阳高度角与太阳天顶角 互余，所以太阳高度角也可以通过90 度-太阳天顶角计算得到(The solar angle is calculated by the solar zenith angle and the sun azimuth angle corresponding to the earth's surface point. The sun height angle and the sun zenith angle are complementary, so the sun height angle can also be calculated by the 90 degree sun zenith angle.)

若矩阵A中的某一元素A[i，j]是第i行中的最小值，而又是第j列中的最大值，则称A[i，j]为矩阵A中的一个鞍点。请写出一个可确定此鞍点位置的算法（如果这个鞍点存在）。(If the matrix A, an element A [i, j] is the minimum value in the i-th row, but is the maximum value of the j-th column, then A [i, j] for the matrix A is a saddle point. Please write a algorithm to determine the position of saddle point (saddle point exists).)

ER随机图算法，matlab程序，复杂网络仿真(ER random graph algorithms, Matlab procedures, complex network simulation)

采用时域数值仿真算法较为精确的仿真铣削加工过程动态力(By using numerical simulation algorithm is more accurate simulation of milling process dynamic force)

说明：  本程序基于matlab进行了声波在固体中的仿真模拟。(This procedure carried out based on sound waves in matlab in the simulation of solid.)

基于最小二乘法的离散数据的曲面拟合，有二次拟合和三次拟合，并能自动出图(Based on the least squares method of discrete data of the surface fitting, there are quadratic fitting and three fitting, and can automatically plot)

自己编写的变步长龙格库塔方法解强非线性微分方程(their preparation variable step Changlong lattice-Kutta method to solve nonlinear differential equations)

说明：  最优化课程中的最速下降法matlab程序，利用了wolfe搜索和armijo线搜索(Matlab program of steepest descent method in optimization course, using Wolfe search and Armijo line search)