R Packages

A package is a collection of R functions, example data, and precompiled code, including R programs, documentation, examples, test data, etc.

R language packages are generally stored in the "library" directory under the installation directory. By default, after R is installed, it comes with some commonly used packages. Of course, we can also customize and add some packages to use later.

The complete list of R language packages can be found at:https://cran.r-project.org/web/packages/available_packages_by_name.html

Next, we will mainly introduce how to install R language packages.

View R package installation directory

We can use the following function to view the installation directory of R packages:

View installed packages

We can use the following function to view installed packages:

library()

The output result is as follows:

base                    The R Base Package
boot                    Bootstrap Functions (Originally by Angelo Canty
                        for S)
class                   Functions for Classification
cluster                 "Finding Groups in Data": Cluster Analysis
                        Extended Rousseeuw et al.
codetools               Code Analysis Tools for R
compiler                The R Compiler Package
datasets                The R Datasets Package
foreign                 Read Data Stored by 'Minitab', 'S', 'SAS',
                        'SPSS', 'Stata', 'Systat', 'Weka', 'dBase', ...
graphics                The R Graphics Package
grDevices               The R Graphics Devices and Support for Colours
                        and Fonts
grid                    The Grid Graphics Package
KernSmooth              Functions for Kernel Smoothing Supporting Wand
                        & Jones (1995)
lattice                 Trellis Graphics for R
MASS                    Support Functions and Datasets for Venables and
                        Ripley's MASS

View loaded packages

We can use the following function to view the packages loaded in the R environment:

---

Install new packages

To install new packages, you can use theinstall.packages()function, with the following format:

install.packages("要安装的包名")

We can directly set the package name and obtain it fromCRANthe website. In the following example, we load the XML package:

# 安装 XML 包
install.packages("XML")

Alternatively, we can directlyCRANdownload the relevant package from the website and install it locally:

install.packages("./XML_3.98-1.3.zip")

In China, we generally recommend using domestic mirrors. The following example uses the University of Science and Technology of China (USTC) source for installation:

# 安装 XML 包
install.packages("XML", repos = "https://mirrors.ustc.edu.cn/CRAN/")

One of the CRAN (The Comprehensive R Archive Network) mirror source configuration files is .Rprofile (located at ~/.Rprofile on Linux).

Add the following statement at the end of the file:

options("repos" = c(CRAN="https://mirrors.tuna.tsinghua.edu.cn/CRAN/"))

Open R to use this CRAN mirror source to install R packages.

Using packages

Newly installed packages need to be loaded into the R environment before they can be used. The format is as follows:

library("包名")

The following example loads the XML package:

library("XML")

Other extensions