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说明：  本书是为理工科大学各专业普遍开设的“数值分析”课程编写的教材 . 其内容包括插值与逼近 ,数值微分与数值积分 , 非线性方程与线性方程组的数值解法 , 矩阵的特征值与特征向量计算 , 常微分方程数值解法 . 每章附有习题并在书末有部分答案 ,书末还附有计算实习题和并行算法简介 . 全书阐述严谨, 脉络分明 ,深入浅出 ,便于教学 .(This book is a textbook for the course of "numerical analysis" which is widely offered in various majors of universities of science and engineering. Its contents include interpolation and approximation, numerical differentiation and numerical integration, numerical solution of non-linear and linear equations, calculation of eigenvalues and eigenvectors of matrices, numerical solution of ordinary differential equations. At the end of the book, there are some answers. At the end of the book, there are also a brief introduction of computational practice questions and parallel algorithms. The whole book elaborates rigorously, clearly, thoroughly and shallowly, which is convenient for teaching.)

北京航空航天大学数值分析大作业第二题，有难度，这可是历年北航研究生转载最多的代码了(Beijing University of Aeronautics and Astronautics numerical analysis of large operating the second question, there is difficulty, this is the most over the years Beihang University Graduate reproduced the code)

船舶荷载计算程序，可用于码头设计中船舶荷载的计算。(Ship load calculation procedures, can be used for ship loading terminal design calculations.)

The Fast Hartley Transform (FHT) implementation.

用C语言编写的1D-FDTD程序，含一阶mur边界，附结果matlab画图程序(Using C language 1D-FDTD procedures, including an order Mur boundary, with results of MATLAB drawing program)

用C语言实现二重积分数值计算，精度较高；并且仿照程序中实现二重积分的思想，可以很容易扩展到三重以上的积分。(Using C language to achieve double integral numerical calculation, high accuracy and follow the procedures realize the idea of double integral, can be easily extended to more than triple the points.)

★问题描述: 给出平面上的N 个二维点，求出距离最小的2 个点对。本题中距离定义为他们的直 线距离。例如(0,0) (3,4)的距离为5. ★数据输入： 有多组数据，对于每组数据，第一行是一个数字N 表示点的个数。N=0 的时候说明 输入结束。之后N 行，每行有2 个浮点数x_i,y_i 表示第i 个点的坐标。(1<=N<=10000 0,0<=|x_i|,|y_i|<=10^9) ★结果输出: 输出一个浮点数，表示最近点对的距离除以2，保留2 位小数(四舍五入)。

打靶法求解两点边值问题 实例测试通过，可直接运行，并带有详细代码注释 采用全局收敛的牛顿-拉普森迭代算法求解编制问题 绝对物超所值！(Two-point boundary value problem shooting method)

用于FLUENT计算结构单自由度涡激振动，采用四阶龙哥库塔法，并设置了并行计算(FLUENT, VIV, Fourth order Runge-Kutta )

Description 设a[0…n-1]是一个包含n个数的数组，若在i<j的情况下，有a[i]>a[j]，则称(i, j)为a数组的一个逆序对（inversion）。 比如 <2,3,8,6,1> 有5个逆序对。请采用类似“合并排序算法”的分治思路以O(nlogn)的效率来实现逆序对的统计。 一个n个元素序列的逆序对个数由三部分构成： （1）它的左半部分逆序对的个数，（2）加上右半部分逆序对的个数，（3）再加上左半部分元素大于右半部分元素的数量。 其中前两部分（1）和（2）由递归来实现。要保证算法最后效率O(nlogn)，第三部分（3）应该如何实现？ 此题请勿采用O(n^2)的简单枚举算法来实现。 并思考如下问题： （1）怎样的数组含有最多的逆序对？最多的又是多少个呢？ （2）插入排序的运行时间和数组中逆序对的个数有关系吗？什么关系？ 输入格式 第一行：n，表示接下来要输入n个元素，n不超过10000。 第二行：n个元素序列。 输出格式 逆序对的个数。 输入样例 5 2 3 8 6 1 输出样例 5(Set a[0... N-1] is a n array containing n numbers. If there is a [i] > a [j] i n the case of I < j, then (i, j) is a n inversion pair of a array. For example, <2,3,8,6,1> has five reverse pairs. Please use the idea of "merge sorting algorithm" to achieve the statistics of inverse pairs with O (nlogn) efficiency. The number of inverse pairs of a sequence of n elements consists of three parts: (1) The number of reverse pairs in the left half, (2) the number of reverse pairs in the right half, (3) the number of elements in the left half is greater than that in the right half. The first two parts (1) and (2) are implemented by recursion. To ensure the final efficiency of the algorithm O (nlogn), how should the third part (3) be implemented? Do not use O (n ^ 2) simple enumeration algorithm to solve this problem.)