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<h1 class="title toc-ignore">Tibbles</h1>
<p>Tibbles are a modern take on data frames. They keep the features that
have stood the test of time, and drop the features that used to be
convenient but are now frustrating.</p>
<div class="sourceCode" id="cb1"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">library</span>(tibble)</span></code></pre></div>
<div id="creating" class="section level2">
<h2>Creating</h2>
<p><code>tibble()</code> is a nice way to create data frames. It
encapsulates best practices for data frames:</p>
<ul>
<li><p>It never changes an input’s type (i.e., no more
<code>stringsAsFactors = FALSE</code>!).</p>
<div class="sourceCode" id="cb2"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">x =</span> letters)</span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 26 × 1</span></span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; x </span></span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;chr&gt;</span></span>
<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 a </span></span>
<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 b </span></span>
<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 c </span></span>
<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 d </span></span>
<span id="cb2-9"><a href="#cb2-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 e </span></span>
<span id="cb2-10"><a href="#cb2-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 6 f </span></span>
<span id="cb2-11"><a href="#cb2-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 7 g </span></span>
<span id="cb2-12"><a href="#cb2-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 8 h </span></span>
<span id="cb2-13"><a href="#cb2-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 9 i </span></span>
<span id="cb2-14"><a href="#cb2-14" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 10 j </span></span>
<span id="cb2-15"><a href="#cb2-15" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 16 more rows</span></span></code></pre></div>
<p>This makes it easier to use with list-columns:</p>
<div class="sourceCode" id="cb3"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">x =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">y =</span> <span class="fu">list</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">5</span>, <span class="dv">1</span><span class="sc">:</span><span class="dv">10</span>, <span class="dv">1</span><span class="sc">:</span><span class="dv">20</span>))</span>
<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 3 × 2</span></span>
<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; x y </span></span>
<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 &lt;int [5]&gt; </span></span>
<span id="cb3-6"><a href="#cb3-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 2 &lt;int [10]&gt;</span></span>
<span id="cb3-7"><a href="#cb3-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 &lt;int [20]&gt;</span></span></code></pre></div>
<p>List-columns are often created by <code>tidyr::nest()</code>, but
they can be useful to create by hand.</p></li>
<li><p>It never adjusts the names of variables:</p>
<div class="sourceCode" id="cb4"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="fu">names</span>(<span class="fu">data.frame</span>(<span class="st">`</span><span class="at">crazy name</span><span class="st">`</span> <span class="ot">=</span> <span class="dv">1</span>))</span>
<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;crazy.name&quot;</span></span>
<span id="cb4-3"><a href="#cb4-3" aria-hidden="true" tabindex="-1"></a><span class="fu">names</span>(<span class="fu">tibble</span>(<span class="st">`</span><span class="at">crazy name</span><span class="st">`</span> <span class="ot">=</span> <span class="dv">1</span>))</span>
<span id="cb4-4"><a href="#cb4-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;crazy name&quot;</span></span></code></pre></div></li>
<li><p>It evaluates its arguments lazily and sequentially:</p>
<div class="sourceCode" id="cb5"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">x =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">5</span>, <span class="at">y =</span> x <span class="sc">^</span> <span class="dv">2</span>)</span>
<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 5 × 2</span></span>
<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; x y</span></span>
<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;dbl&gt;</span></span>
<span id="cb5-5"><a href="#cb5-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1</span></span>
<span id="cb5-6"><a href="#cb5-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 2 4</span></span>
<span id="cb5-7"><a href="#cb5-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 9</span></span>
<span id="cb5-8"><a href="#cb5-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 16</span></span>
<span id="cb5-9"><a href="#cb5-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 5 25</span></span></code></pre></div></li>
<li><p>It never uses <code>row.names()</code>. The whole point of tidy
data is to store variables in a consistent way. So it never stores a
variable as special attribute.</p></li>
<li><p>It only recycles vectors of length 1. This is because recycling
vectors of greater lengths is a frequent source of bugs.</p></li>
</ul>
</div>
<div id="coercion" class="section level2">
<h2>Coercion</h2>
<p>To complement <code>tibble()</code>, tibble provides
<code>as_tibble()</code> to coerce objects into tibbles. Generally,
<code>as_tibble()</code> methods are much simpler than
<code>as.data.frame()</code> methods. The method for lists has been
written with an eye for performance:</p>
<div class="sourceCode" id="cb6"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a>l <span class="ot">&lt;-</span> <span class="fu">replicate</span>(<span class="dv">26</span>, <span class="fu">sample</span>(<span class="dv">100</span>), <span class="at">simplify =</span> <span class="cn">FALSE</span>)</span>
<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="fu">names</span>(l) <span class="ot">&lt;-</span> letters</span>
<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a>timing <span class="ot">&lt;-</span> bench<span class="sc">::</span><span class="fu">mark</span>(</span>
<span id="cb6-5"><a href="#cb6-5" aria-hidden="true" tabindex="-1"></a> <span class="fu">as_tibble</span>(l),</span>
<span id="cb6-6"><a href="#cb6-6" aria-hidden="true" tabindex="-1"></a> <span class="fu">as.data.frame</span>(l),</span>
<span id="cb6-7"><a href="#cb6-7" aria-hidden="true" tabindex="-1"></a> <span class="at">check =</span> <span class="cn">FALSE</span></span>
<span id="cb6-8"><a href="#cb6-8" aria-hidden="true" tabindex="-1"></a>)</span>
<span id="cb6-9"><a href="#cb6-9" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb6-10"><a href="#cb6-10" aria-hidden="true" tabindex="-1"></a>timing</span></code></pre></div>
<pre><code>#&gt; # A tibble: 2 × 14
#&gt; expression min mean median max `itr/sec` mem_a…¹
#&gt; &lt;chr&gt; &lt;bench_tm&gt; &lt;bench_tm&gt; &lt;bench_tm&gt; &lt;bench_tm&gt; &lt;dbl&gt; &lt;bnch_&gt;
#&gt; 1 as_tibble(… 0.000287696 0.0006251376 0.000327178 0.004508219 1599.648 1840
#&gt; 2 as.data.fr… 0.000791522 0.0016640039 0.001098172 0.007652914 600.9601 34584
#&gt; # … with 7 more variables: n_gc &lt;dbl&gt;, n_itr &lt;int&gt;, total_time &lt;bench_tm&gt;,
#&gt; # result &lt;list&gt;, memory &lt;list&gt;, time &lt;list&gt;, gc &lt;list&gt;, and abbreviated
#&gt; # variable name ¹​mem_alloc</code></pre>
<p>The speed of <code>as.data.frame()</code> is not usually a bottleneck
when used interactively, but can be a problem when combining thousands
of messy inputs into one tidy data frame.</p>
</div>
<div id="tibbles-vs-data-frames" class="section level2">
<h2>Tibbles vs data frames</h2>
<p>There are three key differences between tibbles and data frames:
printing, subsetting, and recycling rules.</p>
<div id="printing" class="section level3">
<h3>Printing</h3>
<p>When you print a tibble, it only shows the first ten rows and all the
columns that fit on one screen. It also prints an abbreviated
description of the column type, and uses font styles and color for
highlighting:</p>
<div class="sourceCode" id="cb8"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">x =</span> <span class="sc">-</span><span class="dv">5</span><span class="sc">:</span><span class="dv">100</span>, <span class="at">y =</span> <span class="fl">123.456</span> <span class="sc">*</span> (<span class="dv">3</span><span class="sc">^</span>x))</span>
<span id="cb8-2"><a href="#cb8-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 106 × 2</span></span>
<span id="cb8-3"><a href="#cb8-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; x y</span></span>
<span id="cb8-4"><a href="#cb8-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;dbl&gt;</span></span>
<span id="cb8-5"><a href="#cb8-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 -5 0.5080494</span></span>
<span id="cb8-6"><a href="#cb8-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 -4 1.524148 </span></span>
<span id="cb8-7"><a href="#cb8-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 -3 4.572444 </span></span>
<span id="cb8-8"><a href="#cb8-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 -2 13.71733 </span></span>
<span id="cb8-9"><a href="#cb8-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 -1 41.152 </span></span>
<span id="cb8-10"><a href="#cb8-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 6 0 123.456 </span></span>
<span id="cb8-11"><a href="#cb8-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 7 1 370.368 </span></span>
<span id="cb8-12"><a href="#cb8-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 8 2 1111.104 </span></span>
<span id="cb8-13"><a href="#cb8-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 9 3 3333.312 </span></span>
<span id="cb8-14"><a href="#cb8-14" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 10 4 9999.936 </span></span>
<span id="cb8-15"><a href="#cb8-15" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 96 more rows</span></span></code></pre></div>
<p>Numbers are displayed with three significant figures by default, and
a trailing dot that indicates the existence of a fractional
component.</p>
<p>You can control the default appearance with options:</p>
<ul>
<li><p><code>options(pillar.print_max = n, pillar.print_min = m)</code>:
if there are more than <code>n</code> rows, print only the first
<code>m</code> rows. Use <code>options(pillar.print_max = Inf)</code> to
always show all rows.</p></li>
<li><p><code>options(pillar.width = n)</code>: use <code>n</code>
character slots horizontally to show the data. If
<code>n &gt; getOption(&quot;width&quot;)</code>, this will result in multiple
tiers. Use <code>options(pillar.width = Inf)</code> to always print all
columns, regardless of the width of the screen.</p></li>
</ul>
<p>See <code>?pillar::pillar_options</code> and
<code>?tibble_options</code> for the available options,
<code>vignette(&quot;types&quot;)</code> for an overview of the type
abbreviations, <code>vignette(&quot;numbers&quot;)</code> for details on the
formatting of numbers, and <code>vignette(&quot;digits&quot;)</code> for a
comparison with data frame printing.</p>
</div>
<div id="subsetting" class="section level3">
<h3>Subsetting</h3>
<p>Tibbles are quite strict about subsetting. <code>[</code> always
returns another tibble. Contrast this with a data frame: sometimes
<code>[</code> returns a data frame and sometimes it just returns a
vector:</p>
<div class="sourceCode" id="cb9"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a>df1 <span class="ot">&lt;-</span> <span class="fu">data.frame</span>(<span class="at">x =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">y =</span> <span class="dv">3</span><span class="sc">:</span><span class="dv">1</span>)</span>
<span id="cb9-2"><a href="#cb9-2" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df1[, <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>])</span>
<span id="cb9-3"><a href="#cb9-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;data.frame&quot;</span></span>
<span id="cb9-4"><a href="#cb9-4" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df1[, <span class="dv">1</span>])</span>
<span id="cb9-5"><a href="#cb9-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;integer&quot;</span></span>
<span id="cb9-6"><a href="#cb9-6" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb9-7"><a href="#cb9-7" aria-hidden="true" tabindex="-1"></a>df2 <span class="ot">&lt;-</span> <span class="fu">tibble</span>(<span class="at">x =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">y =</span> <span class="dv">3</span><span class="sc">:</span><span class="dv">1</span>)</span>
<span id="cb9-8"><a href="#cb9-8" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df2[, <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>])</span>
<span id="cb9-9"><a href="#cb9-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;tbl_df&quot; &quot;tbl&quot; &quot;data.frame&quot;</span></span>
<span id="cb9-10"><a href="#cb9-10" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df2[, <span class="dv">1</span>])</span>
<span id="cb9-11"><a href="#cb9-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;tbl_df&quot; &quot;tbl&quot; &quot;data.frame&quot;</span></span></code></pre></div>
<p>To extract a single column use <code>[[</code> or <code>$</code>:</p>
<div class="sourceCode" id="cb10"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df2[[<span class="dv">1</span>]])</span>
<span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;integer&quot;</span></span>
<span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="fu">class</span>(df2<span class="sc">$</span>x)</span>
<span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;integer&quot;</span></span></code></pre></div>
<p>Tibbles are also stricter with <code>$</code>. Tibbles never do
partial matching, and will throw a warning and return <code>NULL</code>
if the column does not exist:</p>
<div class="sourceCode" id="cb11"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a>df <span class="ot">&lt;-</span> <span class="fu">data.frame</span>(<span class="at">abc =</span> <span class="dv">1</span>)</span>
<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a>df<span class="sc">$</span>a</span>
<span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1</span></span>
<span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb11-5"><a href="#cb11-5" aria-hidden="true" tabindex="-1"></a>df2 <span class="ot">&lt;-</span> <span class="fu">tibble</span>(<span class="at">abc =</span> <span class="dv">1</span>)</span>
<span id="cb11-6"><a href="#cb11-6" aria-hidden="true" tabindex="-1"></a>df2<span class="sc">$</span>a</span>
<span id="cb11-7"><a href="#cb11-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning: Unknown or uninitialised column: `a`.</span></span>
<span id="cb11-8"><a href="#cb11-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
<p>However, tibbles respect the <code>drop</code> argument if it is
provided:</p>
<div class="sourceCode" id="cb12"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="fu">data.frame</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>)[, <span class="st">&quot;a&quot;</span>, drop <span class="ot">=</span> <span class="cn">TRUE</span>]</span>
<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 2 3</span></span>
<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>)[, <span class="st">&quot;a&quot;</span>, drop <span class="ot">=</span> <span class="cn">TRUE</span>]</span>
<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 2 3</span></span></code></pre></div>
<p>Tibbles do not support row names. They are removed when converting to
a tibble or when subsetting:</p>
<div class="sourceCode" id="cb13"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a>df <span class="ot">&lt;-</span> <span class="fu">data.frame</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">row.names =</span> letters[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>])</span>
<span id="cb13-2"><a href="#cb13-2" aria-hidden="true" tabindex="-1"></a><span class="fu">rownames</span>(df)</span>
<span id="cb13-3"><a href="#cb13-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;a&quot; &quot;b&quot; &quot;c&quot;</span></span>
<span id="cb13-4"><a href="#cb13-4" aria-hidden="true" tabindex="-1"></a><span class="fu">rownames</span>(<span class="fu">as_tibble</span>(df))</span>
<span id="cb13-5"><a href="#cb13-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;1&quot; &quot;2&quot; &quot;3&quot;</span></span>
<span id="cb13-6"><a href="#cb13-6" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb13-7"><a href="#cb13-7" aria-hidden="true" tabindex="-1"></a>tbl <span class="ot">&lt;-</span> <span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>)</span>
<span id="cb13-8"><a href="#cb13-8" aria-hidden="true" tabindex="-1"></a><span class="fu">rownames</span>(tbl) <span class="ot">&lt;-</span> letters[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>]</span>
<span id="cb13-9"><a href="#cb13-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning: Setting row names on a tibble is deprecated.</span></span>
<span id="cb13-10"><a href="#cb13-10" aria-hidden="true" tabindex="-1"></a><span class="fu">rownames</span>(tbl)</span>
<span id="cb13-11"><a href="#cb13-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;a&quot; &quot;b&quot; &quot;c&quot;</span></span>
<span id="cb13-12"><a href="#cb13-12" aria-hidden="true" tabindex="-1"></a><span class="fu">rownames</span>(tbl[<span class="dv">1</span>, ])</span>
<span id="cb13-13"><a href="#cb13-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;1&quot;</span></span></code></pre></div>
<p>See <code>vignette(&quot;invariants&quot;)</code> for a detailed comparison
between tibbles and data frames.</p>
</div>
<div id="recycling" class="section level3">
<h3>Recycling</h3>
<p>When constructing a tibble, only values of length 1 are recycled. The
first column with length different to one determines the number of rows
in the tibble, conflicts lead to an error:</p>
<div class="sourceCode" id="cb14"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span>, <span class="at">b =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>)</span>
<span id="cb14-2"><a href="#cb14-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 3 × 2</span></span>
<span id="cb14-3"><a href="#cb14-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; a b</span></span>
<span id="cb14-4"><a href="#cb14-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;int&gt;</span></span>
<span id="cb14-5"><a href="#cb14-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1</span></span>
<span id="cb14-6"><a href="#cb14-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 2</span></span>
<span id="cb14-7"><a href="#cb14-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 3</span></span>
<span id="cb14-8"><a href="#cb14-8" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">b =</span> <span class="dv">1</span>)</span>
<span id="cb14-9"><a href="#cb14-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 3 × 2</span></span>
<span id="cb14-10"><a href="#cb14-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; a b</span></span>
<span id="cb14-11"><a href="#cb14-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;dbl&gt;</span></span>
<span id="cb14-12"><a href="#cb14-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1</span></span>
<span id="cb14-13"><a href="#cb14-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 2 1</span></span>
<span id="cb14-14"><a href="#cb14-14" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 1</span></span>
<span id="cb14-15"><a href="#cb14-15" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">c =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>)</span>
<span id="cb14-16"><a href="#cb14-16" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tibble()`:</span></span>
<span id="cb14-17"><a href="#cb14-17" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Tibble columns must have compatible sizes.</span></span>
<span id="cb14-18"><a href="#cb14-18" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; • Size 3: Existing data.</span></span>
<span id="cb14-19"><a href="#cb14-19" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; • Size 2: Column `c`.</span></span>
<span id="cb14-20"><a href="#cb14-20" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ℹ Only values of size one are recycled.</span></span></code></pre></div>
<p>This also extends to tibbles with <em>zero</em> rows, which is
sometimes important for programming:</p>
<div class="sourceCode" id="cb15"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span>, <span class="at">b =</span> <span class="fu">integer</span>())</span>
<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 0 × 2</span></span>
<span id="cb15-3"><a href="#cb15-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 2 variables: a &lt;dbl&gt;, b &lt;int&gt;</span></span>
<span id="cb15-4"><a href="#cb15-4" aria-hidden="true" tabindex="-1"></a><span class="fu">tibble</span>(<span class="at">a =</span> <span class="fu">integer</span>(), <span class="at">b =</span> <span class="dv">1</span>)</span>
<span id="cb15-5"><a href="#cb15-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 0 × 2</span></span>
<span id="cb15-6"><a href="#cb15-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 2 variables: a &lt;int&gt;, b &lt;dbl&gt;</span></span></code></pre></div>
</div>
<div id="arithmetic-operations" class="section level3">
<h3>Arithmetic operations</h3>
<p>Unlike data frames, tibbles don’t support arithmetic operations on
all columns. The result is silently coerced to a data frame. Do not rely
on this behavior, it may become an error in a forthcoming version.</p>
<div class="sourceCode" id="cb16"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a>tbl <span class="ot">&lt;-</span> <span class="fu">tibble</span>(<span class="at">a =</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="at">b =</span> <span class="dv">4</span><span class="sc">:</span><span class="dv">6</span>)</span>
<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a>tbl <span class="sc">*</span> <span class="dv">2</span></span>
<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; a b</span></span>
<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 2 8</span></span>
<span id="cb16-5"><a href="#cb16-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 4 10</span></span>
<span id="cb16-6"><a href="#cb16-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 6 12</span></span></code></pre></div>
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