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最小二乘法拟合形如f(x)=(a+bx)/(1+cx)的函数（9.2.2(1))，并解决人口预测问题(9.2.2(2))(Least squares fit of the form f (x) = (a+bx)/(1+cx) function (9.2.2 (1)), and to solve the population prediction problem (9.2.2 (2)))

说明：  四级四阶龙格库塔格式，求解微分方程的好算法。(Four fourth-order Runge-Kutta format, a good algorithm for solving differential equations.)

很好用的有关矩阵的各种操作，包括求逆，特征值，特征向量，svd分解等(good part of the matrix of various operations including inverse, eigenvalues, eigenvectors, svd decomposition, etc.)

说明：  用二分法求解一元五次非线性方程的实数解，在高等电路学习中有很好的用途。(One yuan of five nonlinear equations dichotomy solving real solutions, there is a very good use in the higher circuit learning.)

Maximum Flow Graph (Boykov Kolmogorov Algorithm)

基于D2Q9模型的LBM程序，用于计算方腔驱动流，对应何亚玲《格子Boltzmann方法的理论及应用》一书的源码(LBM D2Q9 model-based program used to calculate the square cavity driven flow, which corresponds He Yaling " Lattice Boltzmann Method Theory and Applications," a source book)

C语言矩阵求逆模块,输入矩阵调用此模块即可求出对应的逆矩阵(C language matrix inversion module)

天线组阵中相位差的递推最小二乘估计与滤波(Phase array antenna group recursive least squares estimation and filtering)

求解速度压力耦合的Simple半隐式迭代方法，该方法在计算流体动力学中应用极为广泛(To solve the pressure velocity coupling Simple semi-implicit iterative method, the method applied in the Computational Fluid Dynamics an extremely wide range of)

说明：  最小二乘法拟合曲线的一个小程序，采用C++程序，(Least-squares fitting curve C++ program)