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</li> </ul> </div> </div> </nav> <!-- Header = Title in big + social media Icon + quick description --> <header class="masthead"> <div class="textlanding"> <center><h1>ggplot2 boxplot from continuous variable</h1></center> <hr class="short_hr"> <br> <ul class="list-inline social-buttons"> <li class="list-inline-item"> <a href="https://twitter.com/R_Graph_Gallery"> <i class="fa fa-twitter"></i> </a> </li> <li class="list-inline-item social-buttons"> <a href="https://github.com/holtzy"> <i class="fa fa-github" style="color: white"></i> </a> </li> <li class="list-inline-item social-buttons"> <a href="https://www.linkedin.com/in/yan-holtz-2477534a/"> <i class="fa fa-linkedin"></i> </a> </li> <li class="list-inline-item social-buttons"> <a href="https://www.yan-holtz.com"> <i class="fa fa-home"></i> </a> </li> </ul> <center><p style="max-width: 600px; margin-top: 40px">A <a href="boxplot.html">boxplot</a> summarizes the distribution of a continuous variable. This post explains how to build a boxplot with <a href="ggplot2" class="uri">ggplot2</a> where categories are actually bins of a numeric variable. It is sometimes useful to study the relationship between 2 nnumeric variables.</p></center> <div style="text-align:center"> <a class="btn btn-secondary btn-xl text-uppercase js-scroll-trigger" href='boxplot.html'>Boxplot Section</a> <a class="btn btn-secondary btn-xl text-uppercase js-scroll-trigger" href='https://www.data-to-viz.com/caveat/boxplot.html'>Boxplot pitfalls</a> </div> </div> </header> <!-- STYLE for chart pages but not the rest of tthe website --> <style> img { margin-top: 20px; } </style> <div class="container" style="padding-top: 100px"> <div class="row"> <div class="col-md-6 col-sm-12 align-self-center"> <p>Let’s say we want to study the relationship between 2 numeric variables. It is possible to cut on of them in different bins, and to use the created groups to build a <a href="boxplot.html">boxplot</a>.</p> <p>Here, the numeric variable called <code>carat</code> from the <code>diamonds</code> dataset in cut in 0.5 length bins thanks to the <code>cut_width</code> function. Then, we just need to provide the newly created variable to the X axis of <code>ggplot2</code>.</p> <div class="sourceCode"><pre class="sourceCode r"><code class="sourceCode r"><span class="co"># library</span> <span class="kw">library</span>(ggplot2) <span class="kw">library</span>(dplyr) <span class="kw">library</span>(hrbrthemes) <span class="co"># Start with the diamonds dataset, natively available in R:</span> p <-<span class="st"> </span>diamonds <span class="op">%>%</span> <span class="st"> </span> <span class="st"> </span><span class="co"># Add a new column called 'bin': cut the initial 'carat' in bins</span> <span class="st"> </span><span class="kw">mutate</span>( <span class="dt">bin=</span><span class="kw">cut_width</span>(carat, <span class="dt">width=</span><span class="fl">0.5</span>, <span class="dt">boundary=</span><span class="dv">0</span>) ) <span class="op">%>%</span> <span class="st"> </span> <span class="st"> </span><span class="co"># plot</span> <span class="st"> </span><span class="kw">ggplot</span>( <span class="kw">aes</span>(<span class="dt">x=</span>bin, <span class="dt">y=</span>price) ) <span class="op">+</span> <span class="st"> </span><span class="kw">geom_boxplot</span>(<span class="dt">fill=</span><span class="st">"#69b3a2"</span>) <span class="op">+</span> <span class="st"> </span><span class="kw">theme_ipsum</span>() <span class="op">+</span> <span class="st"> </span><span class="kw">xlab</span>(<span class="st">"Carat"</span>)</code></pre></div> </div> <div class="col-md-6 col-sm-12"> <p><img src="268-ggplot2-boxplot-from-continuous-variable_files/figure-html/unnamed-chunk-2-1.png" width="100%" /></p> </div> </div> <!-- Close container --> </div> <!-- ============================ RELATED SECTION ============================ --> <section class="bg-light" id="portfolio_landing" style="padding-top: 30px; padding-bottom: 30px; margin-top: 100px;"> <div class="container"> <p class="mySeryTitle">Related chart types</p> <hr> <div class="row"> <div class="col-md-2 col-sm-4 portfolio-item" > <a class="portfolio-link" href="violin.html"> <div class="portfolio-hover"> <div class="portfolio-hover-content"> <i class="fa fa-plus fa-3x"></i> </div> </div> <img class="img-fluid" src="img/section/Violin150.png" alt=""> </a> <div class="captionPortfolio">Violin</div> </div> <div class="col-md-2 col-sm-4 portfolio-item"> <a class="portfolio-link" href="density.html"> <div class="portfolio-hover"> <div class="portfolio-hover-content"> <i class="fa fa-plus fa-3x"></i> </div> </div> <img class="img-fluid" src="img/section/Density150.png" alt=""> </a> <div class="captionPortfolio">Density</div> </div> <div class="col-md-2 col-sm-4 portfolio-item"> <a class="portfolio-link" href="histogram.html"> <div class="portfolio-hover"> <div class="portfolio-hover-content"> <i class="fa fa-plus fa-3x"></i> </div> </div> <img class="img-fluid" src="img/section/Histogram150.png" alt=""> </a> <div class="captionPortfolio">Histogram</div> </div> <div class="col-md-2 col-sm-4 portfolio-item"> <a class="portfolio-link" href="boxplot.html"> <div class="portfolio-hover"> <div class="portfolio-hover-content"> <i class="fa fa-plus fa-3x"></i> </div> </div> <img class="img-fluid" src="img/section/Box1150.png" alt=""> </a> <div class="captionPortfolio">Boxplot</div> </div> <div class="col-md-2 col-sm-4 portfolio-item"> <a class="portfolio-link" href="ridgeline.html"> <div class="portfolio-hover"> <div class="portfolio-hover-content"> <i class="fa fa-plus fa-3x"></i> </div> </div> <img class="img-fluid" src="img/section/Joyplot150.png" alt=""> </a> <div class="captionPortfolio">Ridgeline</div> </div> </div> </div> </section> <!-- ============================ CONTACT SECTION ============================ --> <section id="contact" class="bg" style="background-color: white; padding-top: 60px"> <div class="container"> <div class="row"> <div class="col-lg-2 text-center"></div> <div class="col-lg-8 text-center"> <br><br><br> <h2 class="section-heading text-uppercase" style="color: black">Contact</h2> <p>This document is a work by <a href="https://www.yan-holtz.com">Yan Holtz</a>. 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