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数值计算实例，主要有LU分解，龙格库塔法，高斯分解法，欧拉法，曲线拟合，曲线插值(Numerical example)

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)

它是一个计算热通量的c++程序，用udf导入fluent，既可以求解，非常好用的一个，可以作为入门的一个例子学习。(it is a calculated heat flux of c++ program, with udf into fluent, not only can solve, very easy to use one, can be used as a case study entry.)

说明：  fortran弹塑性分析程序，很有用的啊！(fortran plastic analysis program, very useful)

LDL分解法，用于求解大型的线性方程组。此程序中最多能解100维的，速度还不错(LDL decomposition method for solving large-scale linear equations. This procedure can be up to 100 peacekeepers solutions, speed is not bad.)

艾特金迭代法求解线性方程组源代码，在程序中修改方程就可以(Aitkin iterative method for solving linear equations source code, the equation can be modified in the program)

c语言程序编写在经验模态分解，包含三次样条(c language programming in the empirical mode decomposition, contains the cubic spline)

以前用VB6编写的一个计算器，支持常用的数学函数，支持弧度、角度转换，支持简单的函数作图。(A calculator writen by VB6, supports common mathematical functions, support radian, angle conversion, support simple function mapping.)

Wdisp，是基于建造结构计算软件pkpm的结果数据提取文件，方便使用，提取数据后，可用于绘制曲线。(Wdisp, is based on The construction structure calculations software pkpm the results of data extraction files, easy to use, extract data, can be used to draw the curve.)

QR分解法是目前求一般矩阵全部特征值的最有效并广泛应用的方法，一般矩阵先经过正交相似变化成为Hessenberg矩阵，然后再应用QR方法求特征值和特征向量。它是将矩阵分解成一个正规正交矩阵Q与上三角形矩阵R，所以称为QR分解法,(QR decomposition )