R (programming language)

Packages

R packages are collections of functions, documentation, and data that expand R. For example, packages can add reporting features (using packages such as R Markdown, Quarto, knitr, and Sweave) and support for various statistical techniques (such as linear, generalized linear and nonlinear modeling, classical statistical tests, spatial analysis, time-series analysis, and clustering). Ease of package installation and use have contributed to the language's adoption in data science.

Immediately available when starting R after installation, base packages provide the fundamental and necessary syntax and commands for programming, computing, graphics production, basic arithmetic, and statistical functionality.

An example is the MASS package, which bundles functions and datasets to support the textbook Modern Applied Statistics with S by Venables and Ripley.

Installing a package occurs only once. For example, to install the MASS package:

<span id="mwxg"></span><span class="gp" id="mwxw">> </span><span class="nf" id="mwyA">install.packages</span><span class="p" id="mwyQ">(</span><span class="s" id="mwyg">"MASS"</span><span class="p" id="mwyw">)</span>

To load the functions, data, and documentation of a package, one calls the library() function. To load the MASS collection, one can execute the following code:

<span id="mw0A"></span><span class="gp" id="mw0Q">> </span><span class="c1" id="mw0g"># The package name can be enclosed in quotes</span> <span class="gp" id="mw0w">> </span><span class="nf" id="mw1A">library</span><span class="p" id="mw1Q">(</span><span class="s" id="mw1g">"MASS"</span><span class="p" id="mw1w">)</span> <span class="gp" id="mw2A">> </span><span class="c1" id="mw2Q"># But the package name can also be used without quotes</span> <span class="gp" id="mw2g">> </span><span class="nf" id="mw2w">library</span><span class="p" id="mw3A">(</span><span class="n" id="mw3Q">MASS</span><span class="p" id="mw3g">)</span>

The Comprehensive R Archive Network (CRAN) was founded in 1997 by Kurt Hornik and Friedrich Leisch to host R's source code, executable files, documentation, and user-created packages. CRAN's name and scope mimic the Comprehensive TeX Archive Network (CTAN) and the Comprehensive Perl Archive Network (CPAN). CRAN originally had only three mirror sites and twelve contributed packages. As of 30 June 2025, it has 90 mirrors and 22,390 contributed packages. Packages are also available in repositories such as R-Forge, Omegahat, and GitHub.

To provide guidance on the CRAN web site, its Task Views area lists packages that are relevant for specific topics; sample topics include causal inference, finance, genetics, high-performance computing, machine learning, medical imaging, meta-analysis, social sciences, and spatial statistics.

The Bioconductor project provides packages for genomic data analysis, complementary DNA, microarray, and high-throughput sequencing methods.

Community

There are three main groups that help support R software development:

• The R Core Team was founded in 1997 to maintain the R source code. In 2026, it was awarded the Rousseeuw Prize for Statistics for its contributions to statistical research and impact on society.
• The R Foundation for Statistical Computing was founded in April 2003 to provide financial support.
• The R Consortium is a Linux Foundation project to develop R infrastructure.

The R Journal is an open access, academic journal that features short to medium-length articles on the use and development of R. The journal includes articles on packages, programming tips, CRAN news, and foundation news.

The R community hosts many conferences and in-person meetups. These groups include:

• useR!: an annual international R user conference (website)
• Directions in Statistical Computing (DSC) (website)
• R-Ladies: an organization to promote gender diversity in the R community (website)
• SatRdays: R-focused conferences held on Saturdays (website)
• Data Science & AI Conferences (website)
• posit::conf (formerly known as rstudio::conf) (website)
• uRos: an annual conference on the Use of R in Official Statistics (website)

On social media sites such as Twitter, the hashtag #rstats can be used to follow new developments in the R community.

Examples

Hello, World!

The following is a "Hello, World!" program:

<span id="mwAVg"></span><span class="gp" id="mwAVk">> </span><span class="nf" id="mwAVo">print</span><span class="p" id="mwAVs">(</span><span class="s" id="mwAVw">"Hello, World!"</span><span class="p" id="mwAV0">)</span> <span class="go" id="mwAV4">[1] "Hello, World!"</span>

Here is an alternative version, which uses the cat() function:

<span id="mwAWM"></span><span class="gp" id="mwAWQ">> </span><span class="nf" id="mwAWU">cat</span><span class="p" id="mwAWY">(</span><span class="s" id="mwAWc">"Hello, World!"</span><span class="p" id="mwAWg">)</span> <span class="go" id="mwAWk">Hello, World!</span>

Basic syntax

The following examples illustrate the basic syntax of the language and use of the command-line interface.

In R, the generally preferred assignment operator is an arrow made from two characters <-, although = can be used in some cases.

<span id="mwAXs"></span><span class="gp" id="mwAXw">> </span><span class="n" id="mwAX0">x</span><span class="w" id="mwAX4"> </span><span class="o" id="mwAX8"><-</span><span class="w" id="mwAYA"> </span><span class="m" id="mwAYE">1</span><span class="o" id="mwAYI">:</span><span class="m" id="mwAYM">6</span><span class="w" id="mwAYQ"> </span><span class="c1" id="mwAYU"># Create a numeric vector in the current environment</span> <span class="gp" id="mwAYY">> </span><span class="n" id="mwAYc">y</span><span class="w" id="mwAYg"> </span><span class="o" id="mwAYk"><-</span><span class="w" id="mwAYo"> </span><span class="n" id="mwAYs">x</span><span class="o" id="mwAYw">^</span><span class="m" id="mwAY0">2</span><span class="w" id="mwAY4"> </span><span class="c1" id="mwAY8"># Similarly, create a vector based on the values in x.</span> <span class="gp" id="mwAZA">> </span><span class="n" id="mwAZE">y</span><span class="w" id="mwAZI"> </span><span class="c1" id="mwAZM"># Print the vector’s contents.</span> <span class="go" id="mwAZQ">[1] 1 4 9 16 25 36</span> <span class="gp" id="mwAZU">> </span><span class="n" id="mwAZY">z</span><span class="w" id="mwAZc"> </span><span class="o" id="mwAZg"><-</span><span class="w" id="mwAZk"> </span><span class="n" id="mwAZo">x</span><span class="w" id="mwAZs"> </span><span class="o" id="mwAZw">+</span><span class="w" id="mwAZ0"> </span><span class="n" id="mwAZ4">y</span><span class="w" id="mwAZ8"> </span><span class="c1" id="mwAaA"># Create a new vector that is the sum of x and y</span> <span class="gp" id="mwAaE">> </span><span class="n" id="mwAaI">z</span><span class="w" id="mwAaM"> </span><span class="c1" id="mwAaQ"># Return the contents of z to the current environment.</span> <span class="go" id="mwAaU">[1] 2 6 12 20 30 42</span> <span class="gp" id="mwAaY">> </span><span class="n" id="mwAac">z_matrix</span><span class="w" id="mwAag"> </span><span class="o" id="mwAak"><-</span><span class="w" id="mwAao"> </span><span class="nf" id="mwAas">matrix</span><span class="p" id="mwAaw">(</span><span class="n" id="mwAa0">z</span><span class="p" id="mwAa4">,</span><span class="w" id="mwAa8"> </span><span class="n" id="mwAbA">nrow</span><span class="w" id="mwAbE"> </span><span class="o" id="mwAbI">=</span><span class="w" id="mwAbM"> </span><span class="m" id="mwAbQ">3</span><span class="p" id="mwAbU">)</span><span class="w" id="mwAbY"> </span><span class="c1" id="mwAbc"># Create a new matrix that transforms the</span> <span class="go" id="mwAbg"> # vector z into a 3x2 matrix object</span> <span class="gp" id="mwAbk">> </span><span class="n" id="mwAbo">z_matrix</span><span class="w" id="mwAbs"> </span> <span class="go" id="mwAbw"> [,1] [,2]</span> <span class="go" id="mwAb0">[1,] 2 20</span> <span class="go" id="mwAb4">[2,] 6 30</span> <span class="go" id="mwAb8">[3,] 12 42</span> <span class="gp" id="mwAcA">> </span><span class="m" id="mwAcE">2</span><span class="w" id="mwAcI"> </span><span class="o" id="mwAcM">*</span><span class="w" id="mwAcQ"> </span><span class="nf" id="mwAcU">t</span><span class="p" id="mwAcY">(</span><span class="n" id="mwAcc">z_matrix</span><span class="p" id="mwAcg">)</span><span class="w" id="mwAck"> </span><span class="o" id="mwAco">-</span><span class="w" id="mwAcs"> </span><span class="m" id="mwAcw">2</span><span class="w" id="mwAc0"> </span><span class="c1" id="mwAc4"># Transpose the matrix; multiply every element by 2;</span> <span class="go" id="mwAc8"> # subtract 2 from each element in the matrix; and</span> <span class="go" id="mwAdA"> # then return the results to the terminal.</span> <span class="go" id="mwAdE"> [,1] [,2] [,3]</span> <span class="go" id="mwAdI">[1,] 2 10 22</span> <span class="go" id="mwAdM">[2,] 38 58 82</span> <span class="go" id="mwAdQ"># Create a new dataframe object that contains the data from a transposed</span> <span class="go" id="mwAdU"># z_matrix, with row names 'A' and 'B'</span> <span class="gp" id="mwAdY">> </span><span class="n" id="mwAdc">new_df</span><span class="w" id="mwAdg"> </span><span class="o" id="mwAdk"><-</span><span class="w" id="mwAdo"> </span><span class="nf" id="mwAds">data.frame</span><span class="p" id="mwAdw">(</span><span class="nf" id="mwAd0">t</span><span class="p" id="mwAd4">(</span><span class="n" id="mwAd8">z_matrix</span><span class="p" id="mwAeA">),</span><span class="w" id="mwAeE"> </span><span class="n" id="mwAeI">row.names</span><span class="w" id="mwAeM"> </span><span class="o" id="mwAeQ">=</span><span class="w" id="mwAeU"> </span><span class="nf" id="mwAeY">c</span><span class="p" id="mwAec">(</span><span class="s" id="mwAeg">"A"</span><span class="p" id="mwAek">,</span><span class="w" id="mwAeo"> </span><span class="s" id="mwAes">"B"</span><span class="p" id="mwAew">))</span><span class="w" id="mwAe0"> </span> <span class="gp" id="mwAe4">> </span><span class="nf" id="mwAe8">names</span><span class="p" id="mwAfA">(</span><span class="n" id="mwAfE">new_df</span><span class="p" id="mwAfI">)</span><span class="w" id="mwAfM"> </span><span class="o" id="mwAfQ"><-</span><span class="w" id="mwAfU"> </span><span class="nf" id="mwAfY">c</span><span class="p" id="mwAfc">(</span><span class="s" id="mwAfg">"X"</span><span class="p" id="mwAfk">,</span><span class="w" id="mwAfo"> </span><span class="s" id="mwAfs">"Y"</span><span class="p" id="mwAfw">,</span><span class="w" id="mwAf0"> </span><span class="s" id="mwAf4">"Z"</span><span class="p" id="mwAf8">)</span><span class="w" id="mwAgA"> </span><span class="c1" id="mwAgE"># Set the column names of the new_df dataframe as X, Y, and Z.</span> <span class="gp" id="mwAgI">> </span><span class="n" id="mwAgM">new_df</span><span class="w" id="mwAgQ"> </span><span class="c1" id="mwAgU"># Print the current results.</span> <span class="go" id="mwAgY"> X Y Z</span> <span class="go" id="mwAgc">A 2 6 12</span> <span class="go" id="mwAgg">B 20 30 42</span> <span class="gp" id="mwAgk">> </span><span class="n" id="mwAgo">new_df</span><span class="o" id="mwAgs">$</span><span class="n" id="mwAgw">Z</span><span class="w" id="mwAg0"> </span><span class="c1" id="mwAg4"># Output the Z column</span> <span class="go" id="mwAg8">[1] 12 42</span> <span class="gp" id="mwAhA">> </span><span class="n" id="mwAhE">new_df</span><span class="o" id="mwAhI">$</span><span class="n" id="mwAhM">Z</span><span class="w" id="mwAhQ"> </span><span class="o" id="mwAhU">==</span><span class="w" id="mwAhY"> </span><span class="n" id="mwAhc">new_df</span><span class="p" id="mwAhg">[</span><span class="s" id="mwAhk">'Z'</span><span class="p" id="mwAho">]</span><span class="w" id="mwAhs"> </span><span class="o" id="mwAhw">&&</span><span class="w" id="mwAh0"> </span><span class="n" id="mwAh4">new_df</span><span class="p" id="mwAh8">[</span><span class="m" id="mwAiA">3</span><span class="p" id="mwAiE">]</span><span class="w" id="mwAiI"> </span><span class="o" id="mwAiM">==</span><span class="w" id="mwAiQ"> </span><span class="n" id="mwAiU">new_df</span><span class="o" id="mwAiY">$</span><span class="n" id="mwAic">Z</span><span class="w" id="mwAig"> </span><span class="c1" id="mwAik"># The dataframe column Z can be accessed using the syntax $Z, ['Z'], or [3], and the values are the same. </span> <span class="go" id="mwAio">[1] TRUE</span> <span class="gp" id="mwAis">> </span><span class="nf" id="mwAiw">attributes</span><span class="p" id="mwAi0">(</span><span class="n" id="mwAi4">new_df</span><span class="p" id="mwAi8">)</span><span class="w" id="mwAjA"> </span><span class="c1" id="mwAjE"># Print information about attributes of the new_df dataframe</span> <span class="go" id="mwAjI">$names</span> <span class="go" id="mwAjM">[1] "X" "Y" "Z"</span> <span class="go" id="mwAjQ">$row.names</span> <span class="go" id="mwAjU">[1] "A" "B"</span> <span class="go" id="mwAjY">$class</span> <span class="go" id="mwAjc">[1] "data.frame"</span> <span class="gp" id="mwAjg">> </span><span class="nf" id="mwAjk">attributes</span><span class="p" id="mwAjo">(</span><span class="n" id="mwAjs">new_df</span><span class="p" id="mwAjw">)</span><span class="o" id="mwAj0">$</span><span class="n" id="mwAj4">row.names</span><span class="w" id="mwAj8"> </span><span class="o" id="mwAkA"><-</span><span class="w" id="mwAkE"> </span><span class="nf" id="mwAkI">c</span><span class="p" id="mwAkM">(</span><span class="s" id="mwAkQ">"one"</span><span class="p" id="mwAkU">,</span><span class="w" id="mwAkY"> </span><span class="s" id="mwAkc">"two"</span><span class="p" id="mwAkg">)</span><span class="w" id="mwAkk"> </span><span class="c1" id="mwAko"># Access and then change the row.names attribute; this can also be done using the rownames() function</span> <span class="gp" id="mwAks">> </span><span class="n" id="mwAkw">new_df</span> <span class="go" id="mwAk0"> X Y Z</span> <span class="go" id="mwAk4">one 2 6 12</span> <span class="go" id="mwAk8">two 20 30 42</span>

Structure of a function

R can create functions that add new functionality and enable code reuse. Objects created within the body of the function (which are enclosed by curly brackets) remain accessible only from within the function, and any data type may be returned. In R, almost all functions and all user-defined functions are closures.

The following is an example of creating a function to perform an arithmetic calculation:

<span id="mwAmM"></span><span class="c1" id="mwAmQ"># The function's input parameters are x and y.</span> <span class="c1" id="mwAmU"># The function, named f, returns a linear combination of x and y.</span> <span class="n" id="mwAmY">f</span><span class="w" id="mwAmc"> </span><span class="o" id="mwAmg"><-</span><span class="w" id="mwAmk"> </span><span class="kr" id="mwAmo">function</span><span class="p" id="mwAms">(</span><span class="n" id="mwAmw">x</span><span class="p" id="mwAm0">,</span><span class="w" id="mwAm4"> </span><span class="n" id="mwAm8">y</span><span class="p" id="mwAnA">)</span><span class="w" id="mwAnE"> </span><span class="p" id="mwAnI">{</span> <span class="w" id="mwAnM"> </span><span class="n" id="mwAnQ">z</span><span class="w" id="mwAnU"> </span><span class="o" id="mwAnY"><-</span><span class="w" id="mwAnc"> </span><span class="m" id="mwAng">3</span><span class="w" id="mwAnk"> </span><span class="o" id="mwAno">*</span><span class="w" id="mwAns"> </span><span class="n" id="mwAnw">x</span><span class="w" id="mwAn0"> </span><span class="o" id="mwAn4">+</span><span class="w" id="mwAn8"> </span><span class="m" id="mwAoA">4</span><span class="w" id="mwAoE"> </span><span class="o" id="mwAoI">*</span><span class="w" id="mwAoM"> </span><span class="n" id="mwAoQ">y</span> <span class="w" id="mwAoU"> </span><span class="c1" id="mwAoY"># An explicit return() statement is optional--it could be replaced with simply `z` in this case.</span> <span class="w" id="mwAoc"> </span><span class="kr" id="mwAog">return</span><span class="p" id="mwAok">(</span><span class="n" id="mwAoo">z</span><span class="p" id="mwAos">)</span> <span class="p" id="mwAow">}</span> <span class="c1" id="mwAo0"># As an alternative, the last statement executed in a function is returned implicitly.</span> <span class="n" id="mwAo4">f</span><span class="w" id="mwAo8"> </span><span class="o" id="mwApA"><-</span><span class="w" id="mwApE"> </span><span class="kr" id="mwApI">function</span><span class="p" id="mwApM">(</span><span class="n" id="mwApQ">x</span><span class="p" id="mwApU">,</span><span class="w" id="mwApY"> </span><span class="n" id="mwApc">y</span><span class="p" id="mwApg">)</span><span class="w" id="mwApk"> </span><span class="m" id="mwApo">3</span><span class="w" id="mwAps"> </span><span class="o" id="mwApw">*</span><span class="w" id="mwAp0"> </span><span class="n" id="mwAp4">x</span><span class="w" id="mwAp8"> </span><span class="o" id="mwAqA">+</span><span class="w" id="mwAqE"> </span><span class="m" id="mwAqI">4</span><span class="w" id="mwAqM"> </span><span class="o" id="mwAqQ">*</span><span class="w" id="mwAqU"> </span><span class="n" id="mwAqY">y</span>

The following is some output from using the function defined above:

<span id="mwAqo"></span><span class="gp" id="mwAqs">> </span><span class="nf" id="mwAqw">f</span><span class="p" id="mwAq0">(</span><span class="m" id="mwAq4">1</span><span class="p" id="mwAq8">,</span><span class="w" id="mwArA"> </span><span class="m" id="mwArE">2</span><span class="p" id="mwArI">)</span><span class="w" id="mwArM"> </span><span class="c1" id="mwArQ"># 3 * 1 + 4 * 2 = 3 + 8</span> <span class="go" id="mwArU">[1] 11</span> <span class="gp" id="mwArY">> </span><span class="nf" id="mwArc">f</span><span class="p" id="mwArg">(</span><span class="nf" id="mwArk">c</span><span class="p" id="mwAro">(</span><span class="m" id="mwArs">1</span><span class="p" id="mwArw">,</span><span class="w" id="mwAr0"> </span><span class="m" id="mwAr4">2</span><span class="p" id="mwAr8">,</span><span class="w" id="mwAsA"> </span><span class="m" id="mwAsE">3</span><span class="p" id="mwAsI">),</span><span class="w" id="mwAsM"> </span><span class="nf" id="mwAsQ">c</span><span class="p" id="mwAsU">(</span><span class="m" id="mwAsY">5</span><span class="p" id="mwAsc">,</span><span class="w" id="mwAsg"> </span><span class="m" id="mwAsk">3</span><span class="p" id="mwAso">,</span><span class="w" id="mwAss"> </span><span class="m" id="mwAsw">4</span><span class="p" id="mwAs0">))</span><span class="w" id="mwAs4"> </span><span class="c1" id="mwAs8"># Element-wise calculation</span> <span class="go" id="mwAtA">[1] 23 18 25</span> <span class="gp" id="mwAtE">> </span><span class="nf" id="mwAtI">f</span><span class="p" id="mwAtM">(</span><span class="m" id="mwAtQ">1</span><span class="o" id="mwAtU">:</span><span class="m" id="mwAtY">3</span><span class="p" id="mwAtc">,</span><span class="w" id="mwAtg"> </span><span class="m" id="mwAtk">4</span><span class="p" id="mwAto">)</span><span class="w" id="mwAts"> </span><span class="c1" id="mwAtw"># Equivalent to f(c(1, 2, 3), c(4, 4, 4))</span> <span class="go" id="mwAt0">[1] 19 22 25</span>

It is possible to define functions to be used as infix operators by using the special syntax `%name%`, where "name" is the function variable name:

<span id="mwAuM"></span><span class="gp" id="mwAuQ">> </span><span class="n" id="mwAuU">`%sumx2y2%`</span><span class="w" id="mwAuY"> </span><span class="o" id="mwAuc"><-</span><span class="w" id="mwAug"> </span><span class="kr" id="mwAuk">function</span><span class="p" id="mwAuo">(</span><span class="n" id="mwAus">e1</span><span class="p" id="mwAuw">,</span><span class="w" id="mwAu0"> </span><span class="n" id="mwAu4">e2</span><span class="p" id="mwAu8">)</span><span class="w" id="mwAvA"> </span><span class="p" id="mwAvE">{</span><span class="n" id="mwAvI">e1</span><span class="w" id="mwAvM"> </span><span class="o" id="mwAvQ">^</span><span class="w" id="mwAvU"> </span><span class="m" id="mwAvY">2</span><span class="w" id="mwAvc"> </span><span class="o" id="mwAvg">+</span><span class="w" id="mwAvk"> </span><span class="n" id="mwAvo">e2</span><span class="w" id="mwAvs"> </span><span class="o" id="mwAvw">^</span><span class="w" id="mwAv0"> </span><span class="m" id="mwAv4">2</span><span class="p" id="mwAv8">}</span> <span class="gp" id="mwAwA">> </span><span class="m" id="mwAwE">1</span><span class="o" id="mwAwI">:</span><span class="m" id="mwAwM">3</span><span class="w" id="mwAwQ"> </span><span class="o" id="mwAwU">%sumx2y2%</span><span class="w" id="mwAwY"> </span><span class="o" id="mwAwc">-</span><span class="p" id="mwAwg">(</span><span class="m" id="mwAwk">1</span><span class="o" id="mwAwo">:</span><span class="m" id="mwAws">3</span><span class="p" id="mwAww">)</span> <span class="go" id="mwAw0">[1] 2 8 18</span>

Since R version 4.1.0, functions can be written in a short notation (inspired by the lambda calculus), which is useful for passing anonymous functions to higher-order functions:

<span id="mwAxY"></span><span class="gp" id="mwAxc">> </span><span class="nf" id="mwAxg">sapply</span><span class="p" id="mwAxk">(</span><span class="m" id="mwAxo">1</span><span class="o" id="mwAxs">:</span><span class="m" id="mwAxw">5</span><span class="p" id="mwAx0">,</span><span class="w" id="mwAx4"> </span>\<span class="p" id="mwAx8">(</span><span class="n" id="mwAyA">i</span><span class="p" id="mwAyE">)</span><span class="w" id="mwAyI"> </span><span class="n" id="mwAyM">i</span><span class="o" id="mwAyQ">^</span><span class="m" id="mwAyU">2</span><span class="p" id="mwAyY">)</span><span class="w" id="mwAyc"> </span><span class="c1" id="mwAyg"># here \(i) is the same as function(i) </span> <span class="go" id="mwAyk">[1] 1 4 9 16 25</span>

Native pipe operator

In R version 4.1.0, a native pipe operator, |>, was introduced. This operator allows users to chain functions together, rather than using nested function calls.

<span id="mwAzQ"></span><span class="gp" id="mwAzU">> </span><span class="nf" id="mwAzY">nrow</span><span class="p" id="mwAzc">(</span><span class="nf" id="mwAzg">subset</span><span class="p" id="mwAzk">(</span><span class="n" id="mwAzo">mtcars</span><span class="p" id="mwAzs">,</span><span class="w" id="mwAzw"> </span><span class="n" id="mwAz0">cyl</span><span class="w" id="mwAz4"> </span><span class="o" id="mwAz8">==</span><span class="w" id="mwA0A"> </span><span class="m" id="mwA0E">4</span><span class="p" id="mwA0I">))</span><span class="w" id="mwA0M"> </span><span class="c1" id="mwA0Q"># Nested without the pipe character</span> <span class="go" id="mwA0U">[1] 11</span> <span class="gp" id="mwA0Y">> </span><span class="n" id="mwA0c">mtcars</span><span class="w" id="mwA0g"> </span><span class="o" id="mwA0k">|></span><span class="w" id="mwA0o"> </span><span class="nf" id="mwA0s">subset</span><span class="p" id="mwA0w">(</span><span class="n" id="mwA00">cyl</span><span class="w" id="mwA04"> </span><span class="o" id="mwA08">==</span><span class="w" id="mwA1A"> </span><span class="m" id="mwA1E">4</span><span class="p" id="mwA1I">)</span><span class="w" id="mwA1M"> </span><span class="o" id="mwA1Q">|></span><span class="w" id="mwA1U"> </span><span class="nf" id="mwA1Y">nrow</span><span class="p" id="mwA1c">()</span><span class="w" id="mwA1g"> </span><span class="c1" id="mwA1k"># Using the pipe character</span> <span class="go" id="mwA1o">[1] 11</span>

An alternative to nested functions is the use of intermediate objects, rather than the pipe operator:

<span id="mwA14"></span><span class="gp" id="mwA18">> </span><span class="n" id="mwA2A">mtcars_subset_rows</span><span class="w" id="mwA2E"> </span><span class="o" id="mwA2I"><-</span><span class="w" id="mwA2M"> </span><span class="nf" id="mwA2Q">subset</span><span class="p" id="mwA2U">(</span><span class="n" id="mwA2Y">mtcars</span><span class="p" id="mwA2c">,</span><span class="w" id="mwA2g"> </span><span class="n" id="mwA2k">cyl</span><span class="w" id="mwA2o"> </span><span class="o" id="mwA2s">==</span><span class="w" id="mwA2w"> </span><span class="m" id="mwA20">4</span><span class="p" id="mwA24">)</span> <span class="gp" id="mwA28">> </span><span class="n" id="mwA3A">num_mtcars_subset</span><span class="w" id="mwA3E"> </span><span class="o" id="mwA3I"><-</span><span class="w" id="mwA3M"> </span><span class="nf" id="mwA3Q">nrow</span><span class="p" id="mwA3U">(</span><span class="n" id="mwA3Y">mtcars_subset_rows</span><span class="p" id="mwA3c">)</span> <span class="gp" id="mwA3g">> </span><span class="nf" id="mwA3k">print</span><span class="p" id="mwA3o">(</span><span class="n" id="mwA3s">num_mtcars_subset</span><span class="p" id="mwA3w">)</span> <span class="go" id="mwA30">[1] 11</span>

While the pipe operator can produce code that is easier to read, influential R programmers like Hadley Wickham suggest to chain together at most 10-15 lines of code using this operator and saving them into objects having meaningful names to avoid code obfuscation.

Object-oriented programming

The R language has native support for object-oriented programming. There are two native frameworks, the so-called S3 and S4 systems. The former, being more informal, supports single dispatch on the first argument, and objects are assigned to a class simply by setting a "class" attribute in each object. The latter is a system like the Common Lisp Object System (CLOS), with formal classes (also derived from S) and generic methods, which supports multiple dispatch and multiple inheritance

In the example below, summary() is a generic function that dispatches to different methods depending on whether its argument is a numeric vector or a factor:

<span id="mwA5k"></span><span class="gp" id="mwA5o">> </span><span class="n" id="mwA5s">data</span><span class="w" id="mwA5w"> </span><span class="o" id="mwA50"><-</span><span class="w" id="mwA54"> </span><span class="nf" id="mwA58">c</span><span class="p" id="mwA6A">(</span><span class="s" id="mwA6E">"a"</span><span class="p" id="mwA6I">,</span><span class="w" id="mwA6M"> </span><span class="s" id="mwA6Q">"b"</span><span class="p" id="mwA6U">,</span><span class="w" id="mwA6Y"> </span><span class="s" id="mwA6c">"c"</span><span class="p" id="mwA6g">,</span><span class="w" id="mwA6k"> </span><span class="s" id="mwA6o">"a"</span><span class="p" id="mwA6s">,</span><span class="w" id="mwA6w"> </span><span class="kc" id="mwA60">NA</span><span class="p" id="mwA64">)</span> <span class="gp" id="mwA68">> </span><span class="nf" id="mwA7A">summary</span><span class="p" id="mwA7E">(</span><span class="n" id="mwA7I">data</span><span class="p" id="mwA7M">)</span> <span class="go" id="mwA7Q"> Length Class Mode </span> <span class="go" id="mwA7U"> 5 character character </span> <span class="gp" id="mwA7Y">> </span><span class="nf" id="mwA7c">summary</span><span class="p" id="mwA7g">(</span><span class="nf" id="mwA7k">as.factor</span><span class="p" id="mwA7o">(</span><span class="n" id="mwA7s">data</span><span class="p" id="mwA7w">))</span> <span class="go" id="mwA70"> a b c NA's </span> <span class="go" id="mwA74"> 2 1 1 1</span>

Modeling and plotting

The R language has built-in support for data modeling and graphics. The following example shows how R can generate and plot a linear model with residuals.

<span id="mwA8o"></span><span class="c1" id="mwA8s"># Create x and y values</span> <span class="n" id="mwA8w">x</span><span class="w" id="mwA80"> </span><span class="o" id="mwA84"><-</span><span class="w" id="mwA88"> </span><span class="m" id="mwA9A">1</span><span class="o" id="mwA9E">:</span><span class="m" id="mwA9I">6</span> <span class="n" id="mwA9M">y</span><span class="w" id="mwA9Q"> </span><span class="o" id="mwA9U"><-</span><span class="w" id="mwA9Y"> </span><span class="n" id="mwA9c">x</span><span class="o" id="mwA9g">^</span><span class="m" id="mwA9k">2</span> <span class="c1" id="mwA9o"># Linear regression model: y = A + B * x</span> <span class="n" id="mwA9s">model</span><span class="w" id="mwA9w"> </span><span class="o" id="mwA90"><-</span><span class="w" id="mwA94"> </span><span class="nf" id="mwA98">lm</span><span class="p" id="mwA-A">(</span><span class="n" id="mwA-E">y</span><span class="w" id="mwA-I"> </span><span class="o" id="mwA-M">~</span><span class="w" id="mwA-Q"> </span><span class="n" id="mwA-U">x</span><span class="p" id="mwA-Y">)</span> <span class="c1" id="mwA-c"># Display an in-depth summary of the model</span> <span class="nf" id="mwA-g">summary</span><span class="p" id="mwA-k">(</span><span class="n" id="mwA-o">model</span><span class="p" id="mwA-s">)</span> <span class="c1" id="mwA-w"># Create a 2-by-2 layout for figures</span> <span class="nf" id="mwA-0">par</span><span class="p" id="mwA-4">(</span><span class="n" id="mwA-8">mfrow</span><span class="w" id="mwA_A"> </span><span class="o" id="mwA_E">=</span><span class="w" id="mwA_I"> </span><span class="nf" id="mwA_M">c</span><span class="p" id="mwA_Q">(</span><span class="m" id="mwA_U">2</span><span class="p" id="mwA_Y">,</span><span class="w" id="mwA_c"> </span><span class="m" id="mwA_g">2</span><span class="p" id="mwA_k">))</span> <span class="c1" id="mwA_o"># Output diagnostic plots of the model</span> <span class="nf" id="mwA_s">plot</span><span class="p" id="mwA_w">(</span><span class="n" id="mwA_0">model</span><span class="p" id="mwA_4">)</span>

The output from the summary() function in the preceding code block is as follows:

<span id="mwBAM"></span><span class="go" id="mwBAQ">Residuals:</span> <span class="go" id="mwBAU"> 1 2 3 4 5 6 7 8 9 10</span> <span class="go" id="mwBAY"> 3.3333 -0.6667 -2.6667 -2.6667 -0.6667 3.3333</span> <span class="go" id="mwBAc">Coefficients:</span> <span class="go" id="mwBAg"> Estimate Std. Error t value Pr(>|t|) </span> <span class="go" id="mwBAk">(Intercept) -9.3333 2.8441 -3.282 0.030453 * </span> <span class="go" id="mwBAo">x 7.0000 0.7303 9.585 0.000662 ***</span> <span class="go" id="mwBAs">---</span> <span class="go" id="mwBAw">Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1</span> <span class="go" id="mwBA0">Residual standard error: 3.055 on 4 degrees of freedom</span> <span class="go" id="mwBA4">Multiple R-squared: 0.9583, Adjusted R-squared: 0.9478</span> <span class="go" id="mwBA8">F-statistic: 91.88 on 1 and 4 DF, p-value: 0.000662</span>

Mandelbrot set

This example of a Mandelbrot set highlights the use of complex numbers. It models the first 20 iterations of the equation z = z2 + c, where c represents different complex constants.

To run this sample code, it is necessary to first install the package that provides the write.gif() function:

<span id="mwBCI"></span><span class="nf" id="mwBCM">install.packages</span><span class="p" id="mwBCQ">(</span><span class="s" id="mwBCU">"caTools"</span><span class="p" id="mwBCY">)</span>

The sample code is as follows:

<span id="mwBCo"></span><span class="nf" id="mwBCs">library</span><span class="p" id="mwBCw">(</span><span class="n" id="mwBC0">caTools</span><span class="p" id="mwBC4">)</span> <span class="n" id="mwBC8">jet.colors</span><span class="w" id="mwBDA"> </span><span class="o" id="mwBDE"><-</span> <span class="w" id="mwBDI"> </span><span class="nf" id="mwBDM">colorRampPalette</span><span class="p" id="mwBDQ">(</span> <span class="w" id="mwBDU"> </span><span class="nf" id="mwBDY">c</span><span class="p" id="mwBDc">(</span><span class="s" id="mwBDg">"green"</span><span class="p" id="mwBDk">,</span><span class="w" id="mwBDo"> </span><span class="s" id="mwBDs">"pink"</span><span class="p" id="mwBDw">,</span><span class="w" id="mwBD0"> </span><span class="s" id="mwBD4">"#007FFF"</span><span class="p" id="mwBD8">,</span><span class="w" id="mwBEA"> </span><span class="s" id="mwBEE">"cyan"</span><span class="p" id="mwBEI">,</span><span class="w" id="mwBEM"> </span><span class="s" id="mwBEQ">"#7FFF7F"</span><span class="p" id="mwBEU">,</span> <span class="w" id="mwBEY"> </span><span class="s" id="mwBEc">"white"</span><span class="p" id="mwBEg">,</span><span class="w" id="mwBEk"> </span><span class="s" id="mwBEo">"#FF7F00"</span><span class="p" id="mwBEs">,</span><span class="w" id="mwBEw"> </span><span class="s" id="mwBE0">"red"</span><span class="p" id="mwBE4">,</span><span class="w" id="mwBE8"> </span><span class="s" id="mwBFA">"#7F0000"</span><span class="p" id="mwBFE">))</span> <span class="n" id="mwBFI">dx</span><span class="w" id="mwBFM"> </span><span class="o" id="mwBFQ"><-</span><span class="w" id="mwBFU"> </span><span class="m" id="mwBFY">1500</span><span class="w" id="mwBFc"> </span><span class="c1" id="mwBFg"># define width</span> <span class="n" id="mwBFk">dy</span><span class="w" id="mwBFo"> </span><span class="o" id="mwBFs"><-</span><span class="w" id="mwBFw"> </span><span class="m" id="mwBF0">1400</span><span class="w" id="mwBF4"> </span><span class="c1" id="mwBF8"># define height</span> <span class="n" id="mwBGA">C</span><span class="w" id="mwBGE"> </span><span class="o" id="mwBGI"><-</span> <span class="w" id="mwBGM"> </span><span class="nf" id="mwBGQ">complex</span><span class="p" id="mwBGU">(</span> <span class="w" id="mwBGY"> </span><span class="n" id="mwBGc">real</span><span class="w" id="mwBGg"> </span><span class="o" id="mwBGk">=</span><span class="w" id="mwBGo"> </span><span class="nf" id="mwBGs">rep</span><span class="p" id="mwBGw">(</span><span class="nf" id="mwBG0">seq</span><span class="p" id="mwBG4">(</span><span class="m" id="mwBG8">-2.2</span><span class="p" id="mwBHA">,</span><span class="w" id="mwBHE"> </span><span class="m" id="mwBHI">1.0</span><span class="p" id="mwBHM">,</span><span class="w" id="mwBHQ"> </span><span class="n" id="mwBHU">length.out</span><span class="w" id="mwBHY"> </span><span class="o" id="mwBHc">=</span><span class="w" id="mwBHg"> </span><span class="n" id="mwBHk">dx</span><span class="p" id="mwBHo">),</span><span class="w" id="mwBHs"> </span><span class="n" id="mwBHw">each</span><span class="w" id="mwBH0"> </span><span class="o" id="mwBH4">=</span><span class="w" id="mwBH8"> </span><span class="n" id="mwBIA">dy</span><span class="p" id="mwBIE">),</span> <span class="w" id="mwBII"> </span><span class="n" id="mwBIM">imag</span><span class="w" id="mwBIQ"> </span><span class="o" id="mwBIU">=</span><span class="w" id="mwBIY"> </span><span class="nf" id="mwBIc">rep</span><span class="p" id="mwBIg">(</span><span class="nf" id="mwBIk">seq</span><span class="p" id="mwBIo">(</span><span class="m" id="mwBIs">-1.2</span><span class="p" id="mwBIw">,</span><span class="w" id="mwBI0"> </span><span class="m" id="mwBI4">1.2</span><span class="p" id="mwBI8">,</span><span class="w" id="mwBJA"> </span><span class="n" id="mwBJE">length.out</span><span class="w" id="mwBJI"> </span><span class="o" id="mwBJM">=</span><span class="w" id="mwBJQ"> </span><span class="n" id="mwBJU">dy</span><span class="p" id="mwBJY">),</span><span class="w" id="mwBJc"> </span><span class="n" id="mwBJg">times</span><span class="w" id="mwBJk"> </span><span class="o" id="mwBJo">=</span><span class="w" id="mwBJs"> </span><span class="n" id="mwBJw">dx</span><span class="p" id="mwBJ0">)</span> <span class="w" id="mwBJ4"> </span><span class="p" id="mwBJ8">)</span> <span class="c1" id="mwBKA"># reshape as matrix of complex numbers</span> <span class="n" id="mwBKE">C</span><span class="w" id="mwBKI"> </span><span class="o" id="mwBKM"><-</span><span class="w" id="mwBKQ"> </span><span class="nf" id="mwBKU">matrix</span><span class="p" id="mwBKY">(</span><span class="n" id="mwBKc">C</span><span class="p" id="mwBKg">,</span><span class="w" id="mwBKk"> </span><span class="n" id="mwBKo">dy</span><span class="p" id="mwBKs">,</span><span class="w" id="mwBKw"> </span><span class="n" id="mwBK0">dx</span><span class="p" id="mwBK4">)</span> <span class="c1" id="mwBK8"># initialize output 3D array</span> <span class="n" id="mwBLA">X</span><span class="w" id="mwBLE"> </span><span class="o" id="mwBLI"><-</span><span class="w" id="mwBLM"> </span><span class="nf" id="mwBLQ">array</span><span class="p" id="mwBLU">(</span><span class="m" id="mwBLY">0</span><span class="p" id="mwBLc">,</span><span class="w" id="mwBLg"> </span><span class="nf" id="mwBLk">c</span><span class="p" id="mwBLo">(</span><span class="n" id="mwBLs">dy</span><span class="p" id="mwBLw">,</span><span class="w" id="mwBL0"> </span><span class="n" id="mwBL4">dx</span><span class="p" id="mwBL8">,</span><span class="w" id="mwBMA"> </span><span class="m" id="mwBME">20</span><span class="p" id="mwBMI">))</span> <span class="n" id="mwBMM">Z</span><span class="w" id="mwBMQ"> </span><span class="o" id="mwBMU"><-</span><span class="w" id="mwBMY"> </span><span class="m" id="mwBMc">0</span> <span class="c1" id="mwBMg"># loop with 20 iterations</span> <span class="kr" id="mwBMk">for</span><span class="w" id="mwBMo"> </span><span class="p" id="mwBMs">(</span><span class="n" id="mwBMw">k</span><span class="w" id="mwBM0"> </span><span class="kr" id="mwBM4">in</span><span class="w" id="mwBM8"> </span><span class="m" id="mwBNA">1</span><span class="o" id="mwBNE">:</span><span class="m" id="mwBNI">20</span><span class="p" id="mwBNM">)</span><span class="w" id="mwBNQ"> </span><span class="p" id="mwBNU">{</span> <span class="w" id="mwBNY"> </span><span class="c1" id="mwBNc"># the central difference equation</span> <span class="w" id="mwBNg"> </span><span class="n" id="mwBNk">Z</span><span class="w" id="mwBNo"> </span><span class="o" id="mwBNs"><-</span><span class="w" id="mwBNw"> </span><span class="n" id="mwBN0">Z</span><span class="o" id="mwBN4">^</span><span class="m" id="mwBN8">2</span><span class="w" id="mwBOA"> </span><span class="o" id="mwBOE">+</span><span class="w" id="mwBOI"> </span><span class="n" id="mwBOM">C</span> <span class="w" id="mwBOQ"> </span><span class="c1" id="mwBOU"># capture the results</span> <span class="w" id="mwBOY"> </span><span class="n" id="mwBOc">X</span><span class="p" id="mwBOg">[,</span><span class="w" id="mwBOk"> </span><span class="p" id="mwBOo">,</span><span class="w" id="mwBOs"> </span><span class="n" id="mwBOw">k</span><span class="p" id="mwBO0">]</span><span class="w" id="mwBO4"> </span><span class="o" id="mwBO8"><-</span><span class="w" id="mwBPA"> </span><span class="nf" id="mwBPE">exp</span><span class="p" id="mwBPI">(</span><span class="o" id="mwBPM">-</span><span class="nf" id="mwBPQ">abs</span><span class="p" id="mwBPU">(</span><span class="n" id="mwBPY">Z</span><span class="p" id="mwBPc">))</span> <span class="p" id="mwBPg">}</span> <span class="nf" id="mwBPk">write.gif</span><span class="p" id="mwBPo">(</span> <span class="w" id="mwBPs"> </span><span class="n" id="mwBPw">X</span><span class="p" id="mwBP0">,</span> <span class="w" id="mwBP4"> </span><span class="s" id="mwBP8">"Mandelbrot.gif"</span><span class="p" id="mwBQA">,</span> <span class="w" id="mwBQE"> </span><span class="n" id="mwBQI">col</span><span class="w" id="mwBQM"> </span><span class="o" id="mwBQQ">=</span><span class="w" id="mwBQU"> </span><span class="n" id="mwBQY">jet.colors</span><span class="p" id="mwBQc">,</span> <span class="w" id="mwBQg"> </span><span class="n" id="mwBQk">delay</span><span class="w" id="mwBQo"> </span><span class="o" id="mwBQs">=</span><span class="w" id="mwBQw"> </span><span class="m" id="mwBQ0">100</span><span class="p" id="mwBQ4">)</span>

Version names

All R version releases from 2.14.0 onward have codenames that make reference to Peanuts comics and films.

In 2018, core R developer Peter Dalgaard presented a history of R releases since 1997. Some notable early releases before the named releases include the following:

• Version 1.0.0, released on 29 February 2000, a leap day
• Version 2.0.0, released on 4 October 2004, "which at least had a nice ring to it"

The idea of naming R version releases was inspired by the naming system for Debian and Ubuntu versions. Dalgaard noted an additional reason for the use of Peanuts references in R codenames—the humorous observation that "everyone in statistics is a P-nut."

Interfaces

Examples of user interfaces for R

R is installed with a command line console by default, but there are multiple ways to interface with the language:

• Integrated development environment (IDE):
  • R.app (OSX/macOS only)
  • Rattle GUI
  • R Commander
  • RKWard
  • RStudio
  • Positron
  • Tinn-R
• General-purpose IDEs:
  • Eclipse via the StatET plugin
  • Visual Studio via R Tools for Visual Studio.
• Source-code editors:
  • Emacs
  • Vim via the Nvim-R plugin
  • Kate
  • LyX via Sweave
  • WinEdt (website)
  • Jupyter (website)
• Other scripting languages:
  • Python (website)
  • Perl (website)
  • Ruby (source code)
  • F# (website)
  • Julia (source code).
• General-purpose programming languages:
  • Java via the Rserve socket server
  • .NET C# (website)

Statistical frameworks that use R in the background include Jamovi and JASP.

Implementations

The main R implementation is written primarily in C, Fortran, and R itself. Other implementations include the following:

• pretty quick R (pqR), by Radford M. Neal, which attempts to improve memory management.
• Renjin for the Java Virtual Machine.
• CXXR and Riposte written in C++.
• Oracle's FastR built on GraalVM.
• TIBCO Enterprise Runtime for R (TERR) to integrate with Spotfire. (The company also sold S-Plus, a discontinued implementation of the S language.)

Microsoft R Open (MRO) was an R implementation. As of 30 June 2021, Microsoft began to phase out MRO in favor of the CRAN distribution.

Commercial support

Although R is an open-source project, some companies provide commercial support:

• Oracle provides commercial support for its Big Data Appliance, which integrates R into its other products.
• IBM provides commercial support for execution of R within Hadoop.