PIDkinhdien

题目：有1、2、3、4个数字，能组成多少个互不相同且无重复数字的三位数？都是多少？ 1.程序分析：可填在百位、十位、个位的数字都是1、2、3、4。组成所有的排列后再去 　　　　　　掉不满足条件的排列。 (Title: There are numbers 1,2,3,4, how many can be composed of distinct three-digit numbers without repetition? Is how much? 1. Program Analysis: fill in the hundred, ten, a bit of the numbers are 1,2,3,4. Composed of all the permutations and then remove the arrangement does not meet the conditions.)

三维时域有限差分程序，cpml吸收边界，介质表面采用网格均分技术(Three-dimensional finite-difference time-domain algorithm, CPML absorbing boundary, sharing media surface using grid technology)

用c#编写了一套FIR窗口滤波器，其中数据段的提取来自于matlab的混合编程(Written in c# a FIR filter window, including data extracted from the mixture of matlab programming)

enjoy the code that can Count the number of fluorescent cells

金融数量分析编程配套源码，各章内容全面，代码完整，不可多得的资料(Quantitative analysis of financial programming supporting source ，Each chapter is comprehensive, code integrity, a rare)

这是用Matlab编写的贪食蛇游戏，非常好玩，大家可以由此体验Matlab编程的乐趣。(This is prepared in Matlab with snake games, very fun, one can all experience the fun of Matlab programming.)

fft calaculation of dc-dc signal

a signal processing using MATLAB and Simulink

OFDM正交频分复用的基带系统，采用QPSK数字调制，统计系统的误码率(baseband of OFDM ，modulation by QPSK)

基于电压外环，电流解耦内环的三相PWM整流器仿真，电压外环采用PID控制，电流内环采用滑模控制，可以正常运行。(The three-phase PWM rectifier based on the voltage outer loop and the current decoupled inner loop is simulated, the voltage outer loop is controlled by PID, and the current inner loop is controlled by sliding mode.)