big-intger-plus-minus-multiply

很有用的一篇国外关于FDTD算法的学术论文，相信对初学者有很大帮助(Useful in a foreign academic papers on the FDTD method, I believe very helpful for beginners)

电磁场圣经，林为干院士的书,学习电磁场重要材料(EMF Bible, it' s dry academician of the book, an important material for studying the electromagnetic field)

Orthogonal Polynomials Approximation 数值分析，计算正交基多项式的系数 (Given a function f and a set of m >0 distinct points . You are supposed to write a function to approximate f by an orthogonal polynomial using the exact function values at the given m points with a weight assigned to each point . The total error must be no larger than a given tolerance. Format of function int OPA( double (*f)(double t), int m, double x[], double w[], double c[], double*eps ) where the function pointer double (*f)(double t) defines the function f int m is the number of points double x[] contains points double w[] contains the values of a weight function at the given points x[] double c[] contains the coefficients of the approximation polynomial double*eps is passed into the function as the tolerance for the error, and is supposed to be returned as the value of error. The function OPA is supposed to return the degree of the approximation polynomial. Note: a constant Max_n is defined so that if the total error is still not small enough when n = Ma)

说明：  利用pid算法控制电机转速，转速可调，数码管显示，初学者实用(Using PID algorithm to control motor speed, adjustable speed, digital display, beginners practical)

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)

对平面上给定的多点进行多项式曲线的拟合，可设置拟合多项式的次数(Given more points on the plane polynomial curve fitting, you can set the number of polynomial fitting)

说明：  该文件是用C语言实现快速傅里叶变换的源代码，需要的朋友快下载(The document is used C language to achieve fast Fourier transform of the source code, need friends fast download)

根据输入的长宽，计算Rectangle面积周长等功能，并画出在txt文件中(Rectangle Create a class Rectangle with attributes length and width, each of which defaults to 1 a. Provide member functions that calculate the perimeter and the area of the rectangle. b. Also provide set and get functions for the length and width attributes. The set functions should verify that length and width are each integer numbers larger than 0 and less than 20. c. Write draw function to display the Rectangle: in Assignment1. ) d. Write a driver program to test class Rectangle.)

有限元n维实体材料单元，仅供科研用途，拒绝商业使用(N-dimensional finite element solid material element, for scientific purposes, refusing commercial use)

读入红细胞图片，通过中值滤波，开运算算，闭运算，和贴标签等方法获得细胞个数 (Read into the red blood cell picture, opening operation count median filtering, and closing operation, and the labeling methods such as cell number)