r语言批量读取xyz格式文件

r语言配套分析的数据，代码。适合初学者进行使用(R language supporting analysis of data, code. Suitable for beginners)

说明：  通过本书，读者不仅能掌握使用R及相关算法包来快速解决实际问题的方法，而且能从实际问题分析入手，到利用R进行求解，以及对挖掘结果进行分析的全面训练(Through this book, readers can not only master the method of using R and relevant algorithm packages to quickly solve practical problems, but also start from the analysis of practical problems to the comprehensive training of using R to solve problems and analyzing mining results)

双重差分估计 双重差分模型（difference-in-difference，DID）近年来多用于计量经济学中对于公共政策或项目实施效果 的定量评估。 通常大范围的公共政策有别于普通科研性研究，难以保证对于政策实施组和对照组在样本分配上的完全随机。非随机分配政策实施组和对照组的试验称为自然试验（naturaltrial），此类试验存在较显著的特点，即不同组间样本在政策实施前可能存在事前差异，仅通过单一前后对比或横向对比的分析方法会忽略这种差异，继而导致对政策实施效果的有偏估计。(Quantitative evaluation of policy or project implementation effect. Generally, a wide range of public policies is different from general scientific research, and it is difficult to ensure that the sample allocation for the policy implementation group and the control group is completely random. The non-randomly assigned policy implementation group and the control group are called natural trials, which have significant characteristics, i.e. there may be prior differences between the different groups of samples before the implementation of the policy, and this difference will be ignored only through a single pre-and post-comparison or horizontal comparison analysis method, which leads to the policy. Biased estimation of implementation)

说明：  该文档中包含大量代码，首先是一些R语言基本语法练习的，然后是一些机器学习相关的，最后是一些评分卡指标计算、建模相关的。(This document contains a lot of code, first some basic grammar exercises of R language, then some machine learning related, and finally some scorecard index calculation, modeling related.)

说明：  R语言对数据进行Garch-M-Copula建模并利用EM算法估计相应的参数(Garch-m-copula is used to model the data in R language and EM algorithm is used to estimate the corresponding parameters)

水动力模型MIKE21数据后处理 dfsu格式文件导出模拟结果xyz格式文件 R语言可以迅速批量读取xyz文件，并根据文件名排序 以便于后期处理(MIKE 21 export results from dsfu R read numerous xyz files)

利用R语言SEM程序包进行通径分析，简单易学，容易上手(SEM path analysis model)

说明：  进行了常微分方程的建立，并模拟出经典的SIR模型曲线(The ordinary differential equation is established and the classical SIR model curve is simulated)

关于时间序列分析的一些比较简单的例子，有注释。使用R语言编写。(Some examples of time series in R)

很好用的代码 简单操作 且是用R语言编写 真的很好用啊( Conceptually, this is a good model, but all too often people actually implement their code this way.)