June 2020
Beginner to intermediate
522 pages
9h 6m
Chinese
Content preview from R 语言经典实例（原书第 2 版）
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123
第 5 章
数据结构
在第 2 章中讨论过，在 R 中运用向量（vector），便可以得到很多结果。本章对向量
以外的 R 数据结构进行探讨，讨论矩阵（matrix）、列表（list）、因子（factor）、数据
框（data frame）以及 tibble（一种特殊的数据框）等数据结构。如果你学习过数据结
构的相关概念，这里建议你先将它们搁置一边。因为 R 软件的数据结构与其他语言
的数据结构有所不同。在开始介绍本章之前，我们将快速浏览一下 R 中的不同数据
结构。
如果你想要学习技术层面的 R 软件数据结构，我建议你阅读
R in a Nutshell
（
https://oreil.ly/
2wUtwyf
）
和
R Language Definition
（
https://cran.r-project.org/doc/manuals/R-lang.pdf
）
这两本书。本书的注解相对非正式。当我们开始使用 R 软件时，以下这些是我们所希望
了解的概念。
向量
向量的主要性质包括：
向量是同质的
一个向量的所有元素（element）必须具有相同的类型，或者用 R 的术语讲，有相同
的
模式
（mode）。
向量可按照位置进行索引
因此 v[2] 指代向量 v 的第二个元素。
向量可按照多重位置索引，返回一个子向量
因此 v[c(2,3)] 是向量 v 的一个子向量（subvector）， 由 v 的第二个元素和第三
个元素组成。
124
｜
第
5
章
向量的元素可以被命名
向量具有一个名称（names）属性，该属性的长度（length ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.