chapter9 codes&data

说明：  R语言舍选法、极坐标法、Box-Muller变换产生正态随机变量(R Language Rounding Method, Polar Coordinate Method and Box-Muller Transform to Generate Normal Random Variables)

制作pcoa、饼图、venn图、热图、柱状图的脚本，可直接改参数使用，内有注释，适用于微生物多样性(the Script to make PCOA)

SIR。。。。 传染病传播的SIR模型，很全，可直接应用仿真模拟 (SIR model the spread of infectious diseases, it is full, the simulation can be applied directly)(SIR model the spread of infectious diseases, it is full, the simulation can be applied directly)

说明：  利用R语言，根据GARCH模型进行波动率的预测。(GARCH model is used to forecast volatility.)

利用R软件建立混合效应模型，对于不同随机效应参数的混合模型进行对比(develop the mixed-effects models and compare the goodness-of-fit)

说明：  本书提供了快速绘制高质量图形的150多种技巧，每个技巧用来解决一个特定的绘图需求。读者可以通过目录快速定位到自己遇到的问题，查询相应的解决方案。(This book provides more than 150 techniques for quickly drawing high quality graphics, each of which addresses a specific drawing requirement. Readers can quickly locate their own problems through the directory, query the corresponding solution.)

成都市空气中的O3来源及分析，可用于大创项目(O3 source and analysis in air of Chengdu, which can be used in some projects)

说明：  制作pcoa、饼图、venn图、热图、柱状图的脚本，可直接改参数使用，内有注释，适用于微生物多样性(the Script to make PCOA)

实现xgboost算法，对实现分类和预测具有良好的效果(The implementation of xgboost algorithm has a good effect on classification and prediction)

说明：  数据集实体文件名称：中国降水日值0.5°×0.5°格点数据集文件命名由数据集代码（SURF_CLI_CHN_PRE_DAY_GRID_0.5）、年月日标识（YYYYMMDD）组成。具体形式：SURF_CLI_CHN_PRE_DAY_GRID_0.5-YYYYMMDD.TXT(Specific form:SURF_CLI_CHN_PRE_DAY_GRID_0.5-YYYYMMDD.TXT)