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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R
软件导览
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69
3.7.2 解决方案
调用没有参数的 library 函数来查看基本的 R 包列表。使用 installed.packages
命令查看更多 R 包的细节信息。
3.7.3 讨论
不含参数的 library 函数会显示已安装的 R 包列表。
library()
这个一列表可能会很长。在 RStudio 中，它显示在编辑器窗口的新选项卡中。
可以使用 installed.packages 函数获取更多详细信息，该函数以矩阵形式返回有
关计算机中已安装的 R 包的信息。矩阵每行对应一个已安装的 R 包。矩阵的列表示 R
包名称、搜索路径和版本等信息。这些信息来自已经安装的 R 包的内部数据库。
通过通常的索引方法，可以从该矩阵中得到有用的信息。以下代码段调用 installed.
packages 并提取前五个 R 包的 Package 和 Version 列，以便查看每个软件包的安
装版本：
installed.packages()[1:5, c("Package", "Version")]
#> Package Version
#> abind "abind" "1.4-5"
#> ade4 "ade4" "1.7-13"
#> adegenet "adegenet" "2.1.1"
#> analogsea "analogsea" "0.6.6.9110"
#> ape "ape" "5.3"
3.7.4 另请参阅
有关如何将 R 包载入计算机内存的信息，请参阅 3.8 节。
3.8 使用 R
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