R Packages

Building and installing an R package

In R Programming, packages are a collection of functions, data sets and compiled code. Packages are used to collect sets of R functions into a single unit.

The directory where packages are stored is known as ‘library’. R provides many standard sets of packages that are installed during the installation of R.

When we start the R console or RStudio, only the default packages are available by default. Other installed packages must be loaded explicitly.

Get Library Location

To get the library location containing R packages we have to use .libPaths() function:

.libPaths()

Output:

[1] "C:/Users/Nikita/Documents/R/win-library/3.5" "C:/Program Files/R/R-3.5.2/library"

List all packages installed

We can load a package which is already existing and installed on your system using the library() function.

library()

When we execute the above command it produces the following output:

Packages in library ‘C:/Program Files/R/R-3.5.2/library’:
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
Matrix                                     Sparse and Dense Matrix Classes and Methods
methods                                  Formal Methods and Classes
mgcv                                      Mixed GAM Computation Vehicle with Automatic Smoothness
                                              Estimation
nlme                                       Linear and Nonlinear Mixed Effects Models
nnet                                       Feed-Forward Neural Networks and Multinomial Log-Linear   
                                               Models
parallel                                 Support for Parallel computation in R
rpart                                    Recursive Partitioning and Regression Trees
spatial                                  Functions for Kriging and Point Pattern Analysis
splines                                   Regression Spline Functions and Classes
stats                                      The R Stats Package
stats4                                     Statistical Functions using S4 Classes
survival                                   Survival Analysis
tcltk                                       Tcl/Tk Interface
tools                                      Tools for Package Development
translations                            The R Translations Package
utils                                       The R Utils Package

Get all packages currently loaded in the R environment

search()

Output:

[1] ".GlobalEnv"        "tools:rstudio"     "package:stats"     "package:graphics"  "package:grDevices" "package:utils"    
[7] "package:datasets"  "package:methods"   "Autoloads"         "package:base"

Install a New Package

We can install packages to R in two different ways:

  • Installing directly from the CRAN repository
  • Install packages manually
  1. Install Directly from the CRAN

To install the package directly from the CRAN repository we have to use the following command with the package name:

Install.packages("Package Name”)

For example:

install.packages(“XML”)

Output:

package ‘XML’ successfully unpacked and MD5 sums checked

The downloaded binary packages are in

C:\Users\Nikita\AppData\Local\Temp\RtmpCuQHa2\downloaded_packages

  1.   Install Package Manually

https://cran.r-project.org/web/packages/available_packages_by_name.html

Go to the above link to download the package needed. And then run the following command to install this package in the R environment.

Example:

install.packages(file_name_with_path, repos = NULL, type = "source")
# Install the package named "XML"
install.packages("D:/XML_3.98-1.19.zip", repos = NULL, type = "source")

Load Package to library

A package must be loaded to the current R environment. To load the package we have to use the following command:

library("package Name", lib.loc = "path to library")

Maintaining Packages in R

You can update the installed packages with the following command:

update.packages()

You can also check what packages need an update with the following command:

old.packages()

If you want to delete any package from R environment then you can delete it using the following command:

remove.packages("Package Name")
Reference: https://www.rstudio.com/products/rpackages/ https://www.tutorialspoint.com/r/r_packages.htm