R for Data Science (2e)

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<header id="title-block-header" class="quarto-title-block default"> <div class="quarto-title"> <h1 class="title">R for Data Science (2e)</h1> </div> <div class="quarto-title-meta"> </div> </header> <section id="welcome" class="level1 unnumbered"> <h1 class="unnumbered">Welcome</h1><p><img src="cover.jpg" title="R for Data Science (2e)" class="quarto-cover-image img-fluid"></p> <p>This is the website for the 2nd edition of <strong>“R for Data Science”</strong>. This book will teach you how to do data science with R: You’ll learn how to get your data into R, get it into the most useful structure, transform it and visualize.</p> <p>In this book, you will find a practicum of skills for data science. Just as a chemist learns how to clean test tubes and stock a lab, you’ll learn how to clean data and draw plots—and many other things besides. These are the skills that allow data science to happen, and here you will find the best practices for doing each of these things with R. You’ll learn how to use the grammar of graphics, literate programming, and reproducible research to save time. You’ll also learn how to manage cognitive resources to facilitate discoveries when wrangling, visualizing, and exploring data.</p> <p>This website is and will always be free, licensed under the <a href="https://creativecommons.org/licenses/by-nc-nd/3.0/us/">CC BY-NC-ND 3.0</a> License. If you’d like a physical copy of the book, you can order it on <a href="https://www.amazon.com/dp/1492097403?&tag=hadlwick-20">Amazon</a>. If you appreciate reading the book for free and would like to give back, please make a donation to <a href="https://www.doc.govt.nz/kakapo-donate">Kākāpō Recovery</a>: the <a href="https://www.youtube.com/watch?v=9T1vfsHYiKY">kākāpō</a> (which appears on the cover of R4DS) is a critically endangered parrot native to New Zealand; there are only 244 left.</p> <p>If you speak another language, you might be interested in the freely available translations of the 1st edition:</p> <ul> <li><a href="http://es.r4ds.hadley.nz">Spanish</a></li> <li><a href="https://it.r4ds.hadley.nz">Italian</a></li> <li><a href="https://tr.r4ds.hadley.nz">Turkish</a></li> <li><a href="https://pt.r4ds.hadley.nz">Portuguese</a></li> </ul> <p>You can find suggested answers to exercises in the book at <a href="https://mine-cetinkaya-rundel.github.io/r4ds-solutions" class="uri">https://mine-cetinkaya-rundel.github.io/r4ds-solutions</a>.</p> <p>Please note that R4DS uses a <a href="https://contributor-covenant.org/version/2/0/CODE_OF_CONDUCT.html">Contributor Code of Conduct</a>. By contributing to this book, you agree to abide by its terms.</p> <section id="acknowledgements" class="level2 unnumbered"> <h2 class="unnumbered anchored" data-anchor-id="acknowledgements">Acknowledgements</h2> <p>R4DS is hosted by <a href="https://www.netlify.com" class="uri">https://www.netlify.com</a> as part of their support of open source software and communities.</p> </section> </section> </main>  <script id="quarto-html-after-body" type="application/javascript"> window.document.addEventListener("DOMContentLoaded", function (event) { const toggleBodyColorMode = (bsSheetEl) => { const mode = bsSheetEl.getAttribute("data-mode"); const bodyEl = window.document.querySelector("body"); if (mode === "dark") { bodyEl.classList.add("quarto-dark"); bodyEl.classList.remove("quarto-light"); } else { bodyEl.classList.add("quarto-light"); bodyEl.classList.remove("quarto-dark"); } } const toggleBodyColorPrimary = () => { const bsSheetEl = window.document.querySelector("link#quarto-bootstrap"); 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} } } stripColumnClz(note) if (id === null || id.startsWith('sec-')) { // Special case sections, only their first couple elements const container = document.createElement("div"); if (note.children && note.children.length > 2) { container.appendChild(note.children[0].cloneNode(true)); for (let i = 1; i < note.children.length; i++) { const child = note.children[i]; if (child.tagName === "P" && child.innerText === "") { continue; } else { container.appendChild(child.cloneNode(true)); break; } } if (window.Quarto?.typesetMath) { window.Quarto.typesetMath(container); } return container.innerHTML } else { if (window.Quarto?.typesetMath) { window.Quarto.typesetMath(note); } return note.innerHTML; } } else { // Remove any anchor links if they are present const anchorLink = note.querySelector('a.anchorjs-link'); if (anchorLink) { anchorLink.remove(); } if (window.Quarto?.typesetMath) { window.Quarto.typesetMath(note); } if (note.classList.contains("callout")) { return note.outerHTML; } else { return note.innerHTML; } } } for (var i=0; i<xrefs.length; i++) { const xref = xrefs[i]; tippyHover(xref, undefined, function(instance) { instance.disable(); let url = xref.getAttribute('href'); let hash = undefined; if (url.startsWith('#')) { hash = url; } else { try { hash = new URL(url).hash; } catch {} } if (hash) { const id = hash.replace(/^#\/?/, ""); const note = window.document.getElementById(id); if (note !== null) { try { const html = processXRef(id, note.cloneNode(true)); instance.setContent(html); } finally { instance.enable(); instance.show(); } } else { // See if we can fetch this fetch(url.split('#')[0]) .then(res => res.text()) .then(html => { const parser = new DOMParser(); const htmlDoc = parser.parseFromString(html, "text/html"); const note = htmlDoc.getElementById(id); if (note !== null) { const html = processXRef(id, note); instance.setContent(html); } }).finally(() => { instance.enable(); instance.show(); }); } } else { // See if we can fetch a full url (with no hash to target) // This is a special case and we should probably do some content thinning / targeting fetch(url) .then(res => res.text()) .then(html => { const parser = new DOMParser(); const htmlDoc = parser.parseFromString(html, "text/html"); const note = htmlDoc.querySelector('main.content'); if (note !== null) { // This should only happen for chapter cross references // (since there is no id in the URL) // remove the first header if (note.children.length > 0 && note.children[0].tagName === "HEADER") { note.children[0].remove(); } const html = processXRef(null, note); instance.setContent(html); } }).finally(() => { instance.enable(); instance.show(); }); } }, function(instance) { }); } let selectedAnnoteEl; const selectorForAnnotation = ( cell, annotation) => { let cellAttr = 'data-code-cell="' + cell + '"'; let lineAttr = 'data-code-annotation="' + annotation + '"'; const selector = 'span[' + cellAttr + '][' + lineAttr + ']'; return selector; } const selectCodeLines = (annoteEl) => { const doc = window.document; const targetCell = annoteEl.getAttribute("data-target-cell"); const targetAnnotation = annoteEl.getAttribute("data-target-annotation"); const annoteSpan = window.document.querySelector(selectorForAnnotation(targetCell, targetAnnotation)); const lines = annoteSpan.getAttribute("data-code-lines").split(","); const lineIds = lines.map((line) => { return targetCell + "-" + line; }) let top = null; let height = null; let parent = null; if (lineIds.length > 0) { //compute the position of the single el (top and bottom and make a div) const el = window.document.getElementById(lineIds[0]); top = el.offsetTop; height = el.offsetHeight; parent = el.parentElement.parentElement; if (lineIds.length > 1) { const lastEl = window.document.getElementById(lineIds[lineIds.length - 1]); const bottom = lastEl.offsetTop + lastEl.offsetHeight; height = bottom - top; } if (top !== null && height !== null && parent !== null) { // cook up a div (if necessary) and position it let div = window.document.getElementById("code-annotation-line-highlight"); if (div === null) { div = window.document.createElement("div"); div.setAttribute("id", "code-annotation-line-highlight"); div.style.position = 'absolute'; parent.appendChild(div); } div.style.top = top - 2 + "px"; div.style.height = height + 4 + "px"; div.style.left = 0; let gutterDiv = window.document.getElementById("code-annotation-line-highlight-gutter"); if (gutterDiv === null) { gutterDiv = window.document.createElement("div"); gutterDiv.setAttribute("id", "code-annotation-line-highlight-gutter"); gutterDiv.style.position = 'absolute'; const codeCell = window.document.getElementById(targetCell); const gutter = codeCell.querySelector('.code-annotation-gutter'); gutter.appendChild(gutterDiv); } gutterDiv.style.top = top - 2 + "px"; gutterDiv.style.height = height + 4 + "px"; } selectedAnnoteEl = annoteEl; } }; const unselectCodeLines = () => { const elementsIds = ["code-annotation-line-highlight", "code-annotation-line-highlight-gutter"]; elementsIds.forEach((elId) => { const div = window.document.getElementById(elId); if (div) { div.remove(); } }); selectedAnnoteEl = undefined; }; // Handle positioning of the toggle window.addEventListener( "resize", throttle(() => { elRect = undefined; if (selectedAnnoteEl) { selectCodeLines(selectedAnnoteEl); } }, 10) ); function throttle(fn, ms) { let throttle = false; let timer; return (...args) => { if(!throttle) { // first call gets through fn.apply(this, args); throttle = true; } else { // all the others get throttled if(timer) clearTimeout(timer); // cancel #2 timer = setTimeout(() => { fn.apply(this, args); timer = throttle = false; }, ms); } }; } // Attach click handler to the DT const annoteDls = window.document.querySelectorAll('dt[data-target-cell]'); for (const annoteDlNode of annoteDls) { annoteDlNode.addEventListener('click', (event) => { const clickedEl = event.target; if (clickedEl !== selectedAnnoteEl) { unselectCodeLines(); const activeEl = window.document.querySelector('dt[data-target-cell].code-annotation-active'); if (activeEl) { activeEl.classList.remove('code-annotation-active'); } selectCodeLines(clickedEl); clickedEl.classList.add('code-annotation-active'); } else { // Unselect the line unselectCodeLines(); clickedEl.classList.remove('code-annotation-active'); } }); } const findCites = (el) => { const parentEl = el.parentElement; if (parentEl) { const cites = parentEl.dataset.cites; if (cites) { return { el, cites: cites.split(' ') }; } else { return findCites(el.parentElement) } } else { return undefined; } }; var bibliorefs = window.document.querySelectorAll('a[role="doc-biblioref"]'); for (var i=0; i<bibliorefs.length; i++) { const ref = bibliorefs[i]; const citeInfo = findCites(ref); if (citeInfo) { tippyHover(citeInfo.el, function() { var popup = window.document.createElement('div'); citeInfo.cites.forEach(function(cite) { var citeDiv = window.document.createElement('div'); citeDiv.classList.add('hanging-indent'); citeDiv.classList.add('csl-entry'); var biblioDiv = window.document.getElementById('ref-' + cite); if (biblioDiv) { citeDiv.innerHTML = biblioDiv.innerHTML; } popup.appendChild(citeDiv); }); return popup.innerHTML; }); } } }); </script> <nav class="page-navigation"> <div class="nav-page nav-page-previous"> </div> <div class="nav-page nav-page-next"> <a href="./preface-2e.html" class="pagination-link" aria-label="Preface to the second edition"> <span class="nav-page-text">Preface to the second edition</span> <i class="bi bi-arrow-right-short"></i> </a> </div> </nav> </div>  <footer class="footer"> <div class="nav-footer"> <div class="nav-footer-left"> <p>R for Data Science (2e) was written by Hadley Wickham, Mine Çetinkaya-Rundel, and Garrett Grolemund.</p> </div> <div class="nav-footer-center">   <div class="toc-actions d-sm-block d-md-none"><ul><li><a href="https://github.com/hadley/r4ds/edit/main/index.qmd" class="toc-action"><i class="bi bi-github"></i>Edit this page</a></li><li><a href="https://github.com/hadley/r4ds/issues/new" class="toc-action"><i class="bi empty"></i>Report an issue</a></li></ul></div></div> <div class="nav-footer-right"> <p>This book was built with <a href="https://quarto.org/">Quarto</a>.</p> </div> </div> </footer> </body></html>

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