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<h1 class="title toc-ignore">Invariants: Comparing behavior with data
frames</h1>
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<p>This vignette defines invariants for subsetting and subset-assignment
for tibbles, and illustrates where their behaviour differs from data
frames. The goal is to define a small set of invariants that
consistently define how behaviors interact. Some behaviors are defined
using functions of the vctrs package, e.g. <code>vec_slice()</code>,
<code>vec_recycle()</code> and <code>vec_as_index()</code>. Refer to
their documentation for more details about the invariants that they
follow.</p>
<p>The subsetting and subassignment operators for data frames and
tibbles are particularly tricky, because they support both row and
column indexes, both of which are optionally missing. We resolve this by
first defining column access with <code>[[</code> and <code>$</code>,
then column-wise subsetting with <code>[</code>, then row-wise
subsetting, then the composition of both.</p>
<div id="conventions" class="section level2">
<h2>Conventions</h2>
<p>In this article, all behaviors are demonstrated using one example
data frame and its tibble equivalent:</p>
<div class="sourceCode" id="cb1"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">library</span>(tibble)</span>
<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="fu">library</span>(vctrs)</span>
<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a>new_df <span class="ot">&lt;-</span> <span class="cf">function</span>() {</span>
<span id="cb1-4"><a href="#cb1-4" aria-hidden="true" tabindex="-1"></a> df <span class="ot">&lt;-</span> <span class="fu">data.frame</span>(<span class="at">n =</span> <span class="fu">c</span>(1L, <span class="cn">NA</span>, 3L, <span class="cn">NA</span>))</span>
<span id="cb1-5"><a href="#cb1-5" aria-hidden="true" tabindex="-1"></a> df<span class="sc">$</span>c <span class="ot">&lt;-</span> letters[<span class="dv">5</span><span class="sc">:</span><span class="dv">8</span>]</span>
<span id="cb1-6"><a href="#cb1-6" aria-hidden="true" tabindex="-1"></a> df<span class="sc">$</span>li <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">9</span>, <span class="dv">10</span><span class="sc">:</span><span class="dv">11</span>, <span class="dv">12</span><span class="sc">:</span><span class="dv">14</span>, <span class="st">&quot;text&quot;</span>)</span>
<span id="cb1-7"><a href="#cb1-7" aria-hidden="true" tabindex="-1"></a> df</span>
<span id="cb1-8"><a href="#cb1-8" aria-hidden="true" tabindex="-1"></a>}</span>
<span id="cb1-9"><a href="#cb1-9" aria-hidden="true" tabindex="-1"></a>new_tbl <span class="ot">&lt;-</span> <span class="cf">function</span>() {</span>
<span id="cb1-10"><a href="#cb1-10" aria-hidden="true" tabindex="-1"></a> <span class="fu">as_tibble</span>(<span class="fu">new_df</span>())</span>
<span id="cb1-11"><a href="#cb1-11" aria-hidden="true" tabindex="-1"></a>}</span></code></pre></div>
<p>Results of the same code for data frames and tibbles are presented
side by side:</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<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">new_df</span>()</span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 10, 11</span></span>
<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14</span></span>
<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
</td>
<td>
<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">new_tbl</span>()</span>
<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&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 e &lt;dbl [1]&gt;</span></span>
<span id="cb3-6"><a href="#cb3-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt;</span></span>
<span id="cb3-7"><a href="#cb3-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb3-8"><a href="#cb3-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
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</tbody>
</table>
<p>If the results are identical (after converting to a data frame if
necessary), only the tibble result is shown.</p>
<p>Subsetting operations are read-only. The same objects are reused in
all examples:</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>df <span class="ot">&lt;-</span> <span class="fu">new_df</span>()</span>
<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a>tbl <span class="ot">&lt;-</span> <span class="fu">new_tbl</span>()</span></code></pre></div>
<p>Where needed, we also show examples with hierarchical columns
containing a data frame or a matrix:</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>new_tbl2 <span class="ot">&lt;-</span> <span class="cf">function</span>() {</span>
<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a> <span class="fu">tibble</span>(</span>
<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a> <span class="at">tb =</span> tbl,</span>
<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a> <span class="at">m =</span> <span class="fu">diag</span>(<span class="dv">4</span>)</span>
<span id="cb5-5"><a href="#cb5-5" aria-hidden="true" tabindex="-1"></a> )</span>
<span id="cb5-6"><a href="#cb5-6" aria-hidden="true" tabindex="-1"></a>}</span>
<span id="cb5-7"><a href="#cb5-7" aria-hidden="true" tabindex="-1"></a>new_df2 <span class="ot">&lt;-</span> <span class="cf">function</span>() {</span>
<span id="cb5-8"><a href="#cb5-8" aria-hidden="true" tabindex="-1"></a> df2 <span class="ot">&lt;-</span> <span class="fu">new_tbl2</span>()</span>
<span id="cb5-9"><a href="#cb5-9" aria-hidden="true" tabindex="-1"></a> <span class="fu">class</span>(df2) <span class="ot">&lt;-</span> <span class="st">&quot;data.frame&quot;</span></span>
<span id="cb5-10"><a href="#cb5-10" aria-hidden="true" tabindex="-1"></a> <span class="fu">class</span>(df2<span class="sc">$</span>tb) <span class="ot">&lt;-</span> <span class="st">&quot;data.frame&quot;</span></span>
<span id="cb5-11"><a href="#cb5-11" aria-hidden="true" tabindex="-1"></a> df2</span>
<span id="cb5-12"><a href="#cb5-12" aria-hidden="true" tabindex="-1"></a>}</span>
<span id="cb5-13"><a href="#cb5-13" aria-hidden="true" tabindex="-1"></a>df2 <span class="ot">&lt;-</span> <span class="fu">new_df2</span>()</span>
<span id="cb5-14"><a href="#cb5-14" aria-hidden="true" tabindex="-1"></a>tbl2 <span class="ot">&lt;-</span> <span class="fu">new_tbl2</span>()</span></code></pre></div>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<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><span class="fu">new_tbl</span>()</span>
<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb6-5"><a href="#cb6-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb6-6"><a href="#cb6-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt;</span></span>
<span id="cb6-7"><a href="#cb6-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb6-8"><a href="#cb6-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
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<p>For subset assignment (subassignment, for short), we need a fresh
copy of the data for each test. The <code>with_*()</code> functions
(omitted here for brevity) allow for a more concise notation. These
functions take an assignment expression, execute it on a fresh copy of
the data, and return the data for printing. The first example prints
whats really executed, further examples omit this output.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb7"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df<span class="sc">$</span>n <span class="ot">&lt;-</span> <span class="fu">rev</span>(df<span class="sc">$</span>n), <span class="at">verbose =</span> <span class="cn">TRUE</span>)</span>
<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; {</span></span>
<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; df &lt;- new_df()</span></span>
<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; df$n &lt;- rev(df$n)</span></span>
<span id="cb7-5"><a href="#cb7-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; df</span></span>
<span id="cb7-6"><a href="#cb7-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; }</span></span>
<span id="cb7-7"><a href="#cb7-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb7-8"><a href="#cb7-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA e 9</span></span>
<span id="cb7-9"><a href="#cb7-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 3 f 10, 11</span></span>
<span id="cb7-10"><a href="#cb7-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 NA g 12, 13, 14</span></span>
<span id="cb7-11"><a href="#cb7-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 h text</span></span></code></pre></div>
</td>
<td>
<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">with_tbl</span>(tbl<span class="sc">$</span>n <span class="ot">&lt;-</span> <span class="fu">rev</span>(tbl<span class="sc">$</span>n), <span class="at">verbose =</span> <span class="cn">TRUE</span>)</span>
<span id="cb8-2"><a href="#cb8-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; {</span></span>
<span id="cb8-3"><a href="#cb8-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tbl &lt;- new_tbl()</span></span>
<span id="cb8-4"><a href="#cb8-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tbl$n &lt;- rev(tbl$n)</span></span>
<span id="cb8-5"><a href="#cb8-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tbl</span></span>
<span id="cb8-6"><a href="#cb8-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; }</span></span>
<span id="cb8-7"><a href="#cb8-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb8-8"><a href="#cb8-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb8-9"><a href="#cb8-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb8-10"><a href="#cb8-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA e &lt;dbl [1]&gt;</span></span>
<span id="cb8-11"><a href="#cb8-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 3 f &lt;int [2]&gt;</span></span>
<span id="cb8-12"><a href="#cb8-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 NA g &lt;int [3]&gt;</span></span>
<span id="cb8-13"><a href="#cb8-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="column-extraction" class="section level2">
<h2>Column extraction</h2>
<div id="definition-of-xj" class="section level3">
<h3>Definition of <code>x[[j]]</code></h3>
<p><code>x[[j]]</code> is equal to <code>.subset2(x, j)</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<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>tbl[[<span class="dv">1</span>]]</span>
<span id="cb9-2"><a href="#cb9-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<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">.subset2</span>(tbl, <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] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>NB: <code>x[[j]]</code> always returns an object of size
<code>nrow(x)</code> if the column exists.</p>
<p><code>j</code> must be a single number or a string, as enforced by
<code>.subset2(x, j)</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<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="dv">1</span><span class="sc">:</span><span class="dv">2</span>]]</span>
<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] NA</span></span></code></pre></div>
</td>
<td>
<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>tbl[[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>]]</span>
<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error:</span></span>
<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! The `j` argument of</span></span>
<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[[.tbl_df` can&#39;t be a vector of</span></span>
<span id="cb12-5"><a href="#cb12-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; length 2 as of tibble 3.0.0.</span></span>
<span id="cb12-6"><a href="#cb12-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Recursive subsetting is</span></span>
<span id="cb12-7"><a href="#cb12-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; deprecated for tibbles.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<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="fu">c</span>(<span class="st">&quot;n&quot;</span>, <span class="st">&quot;c&quot;</span>)]]</span>
<span id="cb13-2"><a href="#cb13-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in .subset2(x, i, exact = exact): subscript out of bounds</span></span></code></pre></div>
</td>
<td>
<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>tbl[[<span class="fu">c</span>(<span class="st">&quot;n&quot;</span>, <span class="st">&quot;c&quot;</span>)]]</span>
<span id="cb14-2"><a href="#cb14-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[c(&quot;n&quot;, &quot;c&quot;)]]`:</span></span>
<span id="cb14-3"><a href="#cb14-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `c(&quot;n&quot;, &quot;c&quot;)`.</span></span>
<span id="cb14-4"><a href="#cb14-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `c(&quot;n&quot;, &quot;c&quot;)` must be size 1, not 2.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<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>df[[<span class="cn">TRUE</span>]]</span>
<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
<td>
<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="cn">TRUE</span>]]</span>
<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[TRUE]]`:</span></span>
<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `TRUE`.</span></span>
<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ `TRUE` must be numeric or character, not `TRUE`.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb17"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a>df[[mean]]</span>
<span id="cb17-2"><a href="#cb17-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in .subset2(x, i, exact = exact): invalid subscript type &#39;closure&#39;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb18"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a>tbl[[mean]]</span>
<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[mean]]`:</span></span>
<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `mean`.</span></span>
<span id="cb18-4"><a href="#cb18-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ `mean` must be numeric or character, not a function.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p><code>NA</code> indexes, numeric out-of-bounds (OOB) values, and
non-integers throw an error:</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb19"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="cn">NA</span>]]</span>
<span id="cb19-2"><a href="#cb19-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb20"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="cn">NA</span>]]</span>
<span id="cb20-2"><a href="#cb20-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[NA]]`:</span></span>
<span id="cb20-3"><a href="#cb20-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `NA`.</span></span>
<span id="cb20-4"><a href="#cb20-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `NA` must be a location, not an integer `NA`.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb21"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="cn">NA_character_</span>]]</span>
<span id="cb21-2"><a href="#cb21-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb22"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="cn">NA_character_</span>]]</span>
<span id="cb22-2"><a href="#cb22-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[NA_character_]]`:</span></span>
<span id="cb22-3"><a href="#cb22-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `NA_character_`.</span></span>
<span id="cb22-4"><a href="#cb22-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `NA_character_` must be a location, not a character `NA`.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb23"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="cn">NA_integer_</span>]]</span>
<span id="cb23-2"><a href="#cb23-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb24"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="cn">NA_integer_</span>]]</span>
<span id="cb24-2"><a href="#cb24-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[NA_integer_]]`:</span></span>
<span id="cb24-3"><a href="#cb24-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `NA_integer_`.</span></span>
<span id="cb24-4"><a href="#cb24-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `NA_integer_` must be a location, not an integer `NA`.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb25"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="sc">-</span><span class="dv">1</span>]]</span>
<span id="cb25-2"><a href="#cb25-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in .subset2(x, i, exact = exact): invalid negative subscript in get1index &lt;real&gt;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb26"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="sc">-</span><span class="dv">1</span>]]</span>
<span id="cb26-2"><a href="#cb26-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[-1]]`:</span></span>
<span id="cb26-3"><a href="#cb26-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `-1`.</span></span>
<span id="cb26-4"><a href="#cb26-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `-1` must be a positive location, not -1.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb27"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="dv">4</span>]]</span>
<span id="cb27-2"><a href="#cb27-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in .subset2(x, i, exact = exact): subscript out of bounds</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb28"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="dv">4</span>]]</span>
<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[4]]`:</span></span>
<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract columns past the end.</span></span>
<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Location 4 doesn&#39;t exist.</span></span>
<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; There are only 3 columns.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb29"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="fl">1.5</span>]]</span>
<span id="cb29-2"><a href="#cb29-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb30"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="fl">1.5</span>]]</span>
<span id="cb30-2"><a href="#cb30-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[1.5]]`:</span></span>
<span id="cb30-3"><a href="#cb30-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `1.5`.</span></span>
<span id="cb30-4"><a href="#cb30-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Can&#39;t convert from `j` &lt;double&gt; to &lt;integer&gt; due to loss of precision.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb31"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="cn">Inf</span>]]</span>
<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb32"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="cn">Inf</span>]]</span>
<span id="cb32-2"><a href="#cb32-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[[Inf]]`:</span></span>
<span id="cb32-3"><a href="#cb32-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t extract column with `Inf`.</span></span>
<span id="cb32-4"><a href="#cb32-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Can&#39;t convert from `j` &lt;double&gt; to &lt;integer&gt; due to loss of precision.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Character OOB access is silent because a common package idiom is to
check for the absence of a column with
<code>is.null(df[[var]])</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb33"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="st">&quot;x&quot;</span>]]</span>
<span id="cb33-2"><a href="#cb33-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="definition-of-xname" class="section level3">
<h3>Definition of <code>x$name</code></h3>
<p><code>x$name</code> and <code>x$&quot;name&quot;</code> are equal to
<code>x[[&quot;name&quot;]]</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb34"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a>tbl<span class="sc">$</span>n</span>
<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb35"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a>tbl<span class="sc">$</span><span class="st">&quot;n&quot;</span></span>
<span id="cb35-2"><a href="#cb35-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb36"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a>tbl[[<span class="st">&quot;n&quot;</span>]]</span>
<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Unlike data frames, tibbles do not partially match names. Because
<code>df$x</code> is rarely used in packages, it can raise a
warning:</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb37"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a>df<span class="sc">$</span>l</span>
<span id="cb37-2"><a href="#cb37-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[1]]</span></span>
<span id="cb37-3"><a href="#cb37-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 9</span></span>
<span id="cb37-4"><a href="#cb37-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb37-5"><a href="#cb37-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[2]]</span></span>
<span id="cb37-6"><a href="#cb37-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 10 11</span></span>
<span id="cb37-7"><a href="#cb37-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb37-8"><a href="#cb37-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[3]]</span></span>
<span id="cb37-9"><a href="#cb37-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 12 13 14</span></span>
<span id="cb37-10"><a href="#cb37-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb37-11"><a href="#cb37-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[4]]</span></span>
<span id="cb37-12"><a href="#cb37-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;text&quot;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb38"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a>tbl<span class="sc">$</span>l</span>
<span id="cb38-2"><a href="#cb38-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning: Unknown or uninitialised</span></span>
<span id="cb38-3"><a href="#cb38-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; column: `l`.</span></span>
<span id="cb38-4"><a href="#cb38-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb39"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a>df<span class="sc">$</span>not_present</span>
<span id="cb39-2"><a href="#cb39-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb40"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a>tbl<span class="sc">$</span>not_present</span>
<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning: Unknown or uninitialised</span></span>
<span id="cb40-3"><a href="#cb40-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; column: `not_present`.</span></span>
<span id="cb40-4"><a href="#cb40-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<div id="column-subsetting" class="section level2">
<h2>Column subsetting</h2>
<div id="definition-of-xj-1" class="section level3">
<h3>Definition of <code>x[j]</code></h3>
<p><code>j</code> is converted to an integer vector by
<code>vec_as_index(j, ncol(x), names = names(x))</code>. Then
<code>x[c(j_1, j_2, ..., j_n)]</code> is equivalent to
<code>tibble(x[[j_1]], x[[j_2]], ..., x[[j_n]])</code>, keeping the
corresponding column names. This implies that <code>j</code> must be a
numeric or character vector, or a logical vector with length 1 or
<code>ncol(x)</code>.<a href="#fn1" class="footnote-ref" id="fnref1"><sup>1</sup></a></p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb41"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>]</span>
<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb41-3"><a href="#cb41-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c </span></span>
<span id="cb41-4"><a href="#cb41-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt;</span></span>
<span id="cb41-5"><a href="#cb41-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e </span></span>
<span id="cb41-6"><a href="#cb41-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f </span></span>
<span id="cb41-7"><a href="#cb41-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g </span></span>
<span id="cb41-8"><a href="#cb41-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>When subsetting repeated indexes, the resulting column names are
undefined, do not rely on them.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb42"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a>df[<span class="fu">c</span>(<span class="dv">1</span>, <span class="dv">1</span>)]</span>
<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n n.1</span></span>
<span id="cb42-3"><a href="#cb42-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1</span></span>
<span id="cb42-4"><a href="#cb42-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA NA</span></span>
<span id="cb42-5"><a href="#cb42-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 3</span></span>
<span id="cb42-6"><a href="#cb42-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA NA</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb43"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="fu">c</span>(<span class="dv">1</span>, <span class="dv">1</span>)]</span>
<span id="cb43-2"><a href="#cb43-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb43-3"><a href="#cb43-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n n</span></span>
<span id="cb43-4"><a href="#cb43-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt;</span></span>
<span id="cb43-5"><a href="#cb43-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1</span></span>
<span id="cb43-6"><a href="#cb43-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA NA</span></span>
<span id="cb43-7"><a href="#cb43-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 3</span></span>
<span id="cb43-8"><a href="#cb43-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA NA</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>For tibbles with repeated column names, subsetting by name uses the
first matching column.</p>
<p><code>nrow(df[j])</code> equals <code>nrow(df)</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb44"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="fu">integer</span>()]</span>
<span id="cb44-2"><a href="#cb44-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 0</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Tibbles support indexing by a logical matrix, but only if all values
in the returned vector are compatible.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb45"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a>df[<span class="fu">is.na</span>(df)]</span>
<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[1]]</span></span>
<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] NA</span></span>
<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[2]]</span></span>
<span id="cb45-6"><a href="#cb45-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] NA</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb46"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="fu">is.na</span>(tbl)]</span>
<span id="cb46-2"><a href="#cb46-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] NA NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb47"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a>df[<span class="sc">!</span><span class="fu">is.na</span>(df)]</span>
<span id="cb47-2"><a href="#cb47-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[1]]</span></span>
<span id="cb47-3"><a href="#cb47-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1</span></span>
<span id="cb47-4"><a href="#cb47-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-5"><a href="#cb47-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[2]]</span></span>
<span id="cb47-6"><a href="#cb47-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 3</span></span>
<span id="cb47-7"><a href="#cb47-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-8"><a href="#cb47-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[3]]</span></span>
<span id="cb47-9"><a href="#cb47-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;e&quot;</span></span>
<span id="cb47-10"><a href="#cb47-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-11"><a href="#cb47-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[4]]</span></span>
<span id="cb47-12"><a href="#cb47-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;f&quot;</span></span>
<span id="cb47-13"><a href="#cb47-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-14"><a href="#cb47-14" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[5]]</span></span>
<span id="cb47-15"><a href="#cb47-15" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;g&quot;</span></span>
<span id="cb47-16"><a href="#cb47-16" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-17"><a href="#cb47-17" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[6]]</span></span>
<span id="cb47-18"><a href="#cb47-18" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;h&quot;</span></span>
<span id="cb47-19"><a href="#cb47-19" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-20"><a href="#cb47-20" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[7]]</span></span>
<span id="cb47-21"><a href="#cb47-21" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 9</span></span>
<span id="cb47-22"><a href="#cb47-22" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-23"><a href="#cb47-23" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[8]]</span></span>
<span id="cb47-24"><a href="#cb47-24" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 10 11</span></span>
<span id="cb47-25"><a href="#cb47-25" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-26"><a href="#cb47-26" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[9]]</span></span>
<span id="cb47-27"><a href="#cb47-27" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 12 13 14</span></span>
<span id="cb47-28"><a href="#cb47-28" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb47-29"><a href="#cb47-29" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [[10]]</span></span>
<span id="cb47-30"><a href="#cb47-30" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;text&quot;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb48"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="sc">!</span><span class="fu">is.na</span>(tbl)]</span>
<span id="cb48-2"><a href="#cb48-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `vec_c()` at ]8;line = 12:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subsetting-matrix.Rtibble/R/subsetting-matrix.R:12:2]8;;:</span></span>
<span id="cb48-3"><a href="#cb48-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t combine `n` &lt;integer&gt; and `c` &lt;character&gt;.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="definition-of-x-j" class="section level3">
<h3>Definition of <code>x[, j]</code></h3>
<p><code>x[, j]</code> is equal to <code>x[j]</code>. Tibbles do not
perform column extraction if <code>x[j]</code> would yield a single
column.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb49"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a>df[, <span class="dv">1</span>]</span>
<span id="cb49-2"><a href="#cb49-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb50"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a>tbl[, <span class="dv">1</span>]</span>
<span id="cb50-2"><a href="#cb50-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 1</span></span>
<span id="cb50-3"><a href="#cb50-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n</span></span>
<span id="cb50-4"><a href="#cb50-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt;</span></span>
<span id="cb50-5"><a href="#cb50-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1</span></span>
<span id="cb50-6"><a href="#cb50-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA</span></span>
<span id="cb50-7"><a href="#cb50-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3</span></span>
<span id="cb50-8"><a href="#cb50-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb51"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb51-1"><a href="#cb51-1" aria-hidden="true" tabindex="-1"></a>tbl[, <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>]</span>
<span id="cb51-2"><a href="#cb51-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb51-3"><a href="#cb51-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c </span></span>
<span id="cb51-4"><a href="#cb51-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt;</span></span>
<span id="cb51-5"><a href="#cb51-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e </span></span>
<span id="cb51-6"><a href="#cb51-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f </span></span>
<span id="cb51-7"><a href="#cb51-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g </span></span>
<span id="cb51-8"><a href="#cb51-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="definition-of-x-j-drop-true" class="section level3">
<h3>Definition of <code>x[, j, drop = TRUE]</code></h3>
<p>For backward compatiblity, <code>x[, j, drop = TRUE]</code> performs
column <strong>extraction</strong>, returning <code>x[j][[1]]</code>
when <code>ncol(x[j])</code> is 1.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb52"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a>tbl[, <span class="dv">1</span>, drop <span class="ot">=</span> <span class="cn">TRUE</span>]</span>
<span id="cb52-2"><a href="#cb52-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1 NA 3 NA</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<div id="row-subsetting" class="section level2">
<h2>Row subsetting</h2>
<div id="definition-of-xi" class="section level3">
<h3>Definition of <code>x[i, ]</code></h3>
<p><code>x[i, ]</code> is equal to
<code>tibble(vec_slice(x[[1]], i), vec_slice(x[[2]], i), ...)</code>.<a href="#fn2" class="footnote-ref" id="fnref2"><sup>2</sup></a></p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb53"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb53-1"><a href="#cb53-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="dv">3</span>, ]</span>
<span id="cb53-2"><a href="#cb53-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb53-3"><a href="#cb53-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb53-4"><a href="#cb53-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb53-5"><a href="#cb53-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 3 g &lt;int [3]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>This means that <code>i</code> must be a numeric vector, or a logical
vector of length <code>nrow(x)</code> or 1. For compatibility,
<code>i</code> can also be a character vector containing positive
numbers.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb54"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb54-1"><a href="#cb54-1" aria-hidden="true" tabindex="-1"></a>df[mean, ]</span>
<span id="cb54-2"><a href="#cb54-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in xj[i]: invalid subscript type &#39;closure&#39;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb55"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb55-1"><a href="#cb55-1" aria-hidden="true" tabindex="-1"></a>tbl[mean, ]</span>
<span id="cb55-2"><a href="#cb55-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[mean, ]`:</span></span>
<span id="cb55-3"><a href="#cb55-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t subset rows with `mean`.</span></span>
<span id="cb55-4"><a href="#cb55-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ `mean` must be logical, numeric, or character, not a function.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb56"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb56-1"><a href="#cb56-1" aria-hidden="true" tabindex="-1"></a>df[<span class="fu">list</span>(<span class="dv">1</span>), ]</span>
<span id="cb56-2"><a href="#cb56-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in xj[i]: invalid subscript type &#39;list&#39;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb57"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb57-1"><a href="#cb57-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="fu">list</span>(<span class="dv">1</span>), ]</span>
<span id="cb57-2"><a href="#cb57-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[list(1), ]`:</span></span>
<span id="cb57-3"><a href="#cb57-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t subset rows with `list(1)`.</span></span>
<span id="cb57-4"><a href="#cb57-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ `list(1)` must be logical, numeric, or character, not a list.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb58"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb58-1"><a href="#cb58-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="st">&quot;1&quot;</span>, ]</span>
<span id="cb58-2"><a href="#cb58-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb58-3"><a href="#cb58-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb58-4"><a href="#cb58-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb58-5"><a href="#cb58-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Exception: OOB values generate warnings instead of errors:</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb59"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb59-1"><a href="#cb59-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="dv">10</span>, ]</span>
<span id="cb59-2"><a href="#cb59-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb59-3"><a href="#cb59-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb59-4"><a href="#cb59-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt;</span></span>
<span id="cb59-5"><a href="#cb59-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA &lt;NA&gt; &lt;NULL&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb60"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb60-1"><a href="#cb60-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="st">&quot;x&quot;</span>, ]</span>
<span id="cb60-2"><a href="#cb60-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb60-3"><a href="#cb60-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb60-4"><a href="#cb60-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt;</span></span>
<span id="cb60-5"><a href="#cb60-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA &lt;NA&gt; &lt;NULL&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Unlike data frames, only logical vectors of length 1 are recycled.
<!-- TODO: should this be an error? #648 --></p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb61"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb61-1"><a href="#cb61-1" aria-hidden="true" tabindex="-1"></a>df[<span class="fu">c</span>(<span class="cn">TRUE</span>, <span class="cn">FALSE</span>), ]</span>
<span id="cb61-2"><a href="#cb61-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb61-3"><a href="#cb61-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb61-4"><a href="#cb61-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb62"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb62-1"><a href="#cb62-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="fu">c</span>(<span class="cn">TRUE</span>, <span class="cn">FALSE</span>), ]</span>
<span id="cb62-2"><a href="#cb62-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `tbl[c(TRUE, FALSE), ]`:</span></span>
<span id="cb62-3"><a href="#cb62-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t subset rows with `c(TRUE, FALSE)`.</span></span>
<span id="cb62-4"><a href="#cb62-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Logical subscript `c(TRUE, FALSE)` must be size 1 or 4, not 2.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>NB: scalar logicals are recycled, but scalar numerics are not. That
makes the <code>x[NA, ]</code> and <code>x[NA_integer_, ]</code> return
different results.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb63"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb63-1"><a href="#cb63-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="cn">NA</span>, ]</span>
<span id="cb63-2"><a href="#cb63-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb63-3"><a href="#cb63-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb63-4"><a href="#cb63-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt;</span></span>
<span id="cb63-5"><a href="#cb63-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA &lt;NA&gt; &lt;NULL&gt;</span></span>
<span id="cb63-6"><a href="#cb63-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA &lt;NA&gt; &lt;NULL&gt;</span></span>
<span id="cb63-7"><a href="#cb63-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 NA &lt;NA&gt; &lt;NULL&gt;</span></span>
<span id="cb63-8"><a href="#cb63-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA &lt;NA&gt; &lt;NULL&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb64"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb64-1"><a href="#cb64-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="cn">NA_integer_</span>, ]</span>
<span id="cb64-2"><a href="#cb64-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb64-3"><a href="#cb64-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb64-4"><a href="#cb64-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt;</span></span>
<span id="cb64-5"><a href="#cb64-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 NA &lt;NA&gt; &lt;NULL&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="definition-of-xi-drop-true" class="section level3">
<h3>Definition of <code>x[i, , drop = TRUE]</code></h3>
<p><code>drop = TRUE</code> has no effect when not selecting a single
row:</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb65"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb65-1"><a href="#cb65-1" aria-hidden="true" tabindex="-1"></a>df[<span class="dv">1</span>, , drop <span class="ot">=</span> <span class="cn">TRUE</span>]</span>
<span id="cb65-2"><a href="#cb65-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; $n</span></span>
<span id="cb65-3"><a href="#cb65-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1</span></span>
<span id="cb65-4"><a href="#cb65-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb65-5"><a href="#cb65-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; $c</span></span>
<span id="cb65-6"><a href="#cb65-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] &quot;e&quot;</span></span>
<span id="cb65-7"><a href="#cb65-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; </span></span>
<span id="cb65-8"><a href="#cb65-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; $li</span></span>
<span id="cb65-9"><a href="#cb65-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; $li[[1]]</span></span>
<span id="cb65-10"><a href="#cb65-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 9</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb66"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb66-1"><a href="#cb66-1" aria-hidden="true" tabindex="-1"></a>tbl[<span class="dv">1</span>, , drop <span class="ot">=</span> <span class="cn">TRUE</span>]</span>
<span id="cb66-2"><a href="#cb66-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 1 × 3</span></span>
<span id="cb66-3"><a href="#cb66-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb66-4"><a href="#cb66-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb66-5"><a href="#cb66-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<!-- TODO: soft-deprecate -->
</div>
</div>
<div id="row-and-column-subsetting" class="section level2">
<h2>Row and column subsetting</h2>
<div id="definition-of-x-and-x" class="section level3">
<h3>Definition of <code>x[]</code> and <code>x[,]</code></h3>
<p><code>x[]</code> and <code>x[,]</code> are equivalent to
<code>x</code>.<a href="#fn3" class="footnote-ref" id="fnref3"><sup>3</sup></a></p>
</div>
<div id="definition-of-xi-j" class="section level3">
<h3>Definition of <code>x[i, j]</code></h3>
<p><code>x[i, j]</code> is equal to <code>x[i, ][j]</code>.<a href="#fn4" class="footnote-ref" id="fnref4"><sup>4</sup></a></p>
</div>
<div id="definition-of-xi-j-1" class="section level3">
<h3>Definition of <code>x[[i, j]]</code></h3>
<p><code>i</code> must be a numeric vector of length 1.
<code>x[[i, j]]</code> is equal to <code>x[i, ][[j]]</code>, or
<code>vctrs::vec_slice(x[[j]], i)</code>.<a href="#fn5" class="footnote-ref" id="fnref5"><sup>5</sup></a></p>
<div class="sourceCode" id="cb67"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb67-1"><a href="#cb67-1" aria-hidden="true" tabindex="-1"></a>df[[<span class="dv">1</span>, <span class="dv">1</span>]]</span>
<span id="cb67-2"><a href="#cb67-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 1</span></span>
<span id="cb67-3"><a href="#cb67-3" aria-hidden="true" tabindex="-1"></a>df[[<span class="dv">1</span>, <span class="dv">3</span>]]</span>
<span id="cb67-4"><a href="#cb67-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; [1] 9</span></span></code></pre></div>
<p>This implies that <code>j</code> must be a numeric or character
vector of length 1.</p>
<p>NB: <code>vec_size(x[[i, j]])</code> always equals 1. Unlike
<code>x[i, ]</code>, <code>x[[i, ]]</code> is not valid.</p>
</div>
</div>
<div id="column-update" class="section level2">
<h2>Column update</h2>
<div id="definition-of-xj---a" class="section level3">
<h3>Definition of <code>x[[j]] &lt;- a</code></h3>
<p>If <code>a</code> is a vector then <code>x[[j]] &lt;- a</code>
replaces the <code>j</code>th column with value <code>a</code>.</p>
<p><code>a</code> is recycled to the same size as <code>x</code> so must
have size <code>nrow(x)</code> or 1. (The only exception is when
<code>a</code> is <code>NULL</code>, as described below.) Recycling also
works for list, data frame, and matrix columns.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb68"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb68-1"><a href="#cb68-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="st">&quot;li&quot;</span>]] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>))</span>
<span id="cb68-2"><a href="#cb68-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb68-3"><a href="#cb68-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb68-4"><a href="#cb68-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb68-5"><a href="#cb68-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb68-6"><a href="#cb68-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;dbl [1]&gt;</span></span>
<span id="cb68-7"><a href="#cb68-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;dbl [1]&gt;</span></span>
<span id="cb68-8"><a href="#cb68-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;dbl [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb69"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb69-1"><a href="#cb69-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df2</span>(df2[[<span class="st">&quot;tb&quot;</span>]] <span class="ot">&lt;-</span> df[<span class="dv">1</span>, ])</span>
<span id="cb69-2"><a href="#cb69-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[[&lt;-.data.frame`(`*tmp*`, &quot;tb&quot;, value = structure(list(n = 1L, : replacement has 1 row, data has 4</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb70"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb70-1"><a href="#cb70-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl2</span>(tbl2[[<span class="st">&quot;tb&quot;</span>]] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb70-2"><a href="#cb70-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb70-3"><a href="#cb70-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tb$n $c $li m[,1] [,2]</span></span>
<span id="cb70-4"><a href="#cb70-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt; &lt;dbl&gt;</span></span>
<span id="cb70-5"><a href="#cb70-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 1 0</span></span>
<span id="cb70-6"><a href="#cb70-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt; 0 1</span></span>
<span id="cb70-7"><a href="#cb70-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e &lt;dbl [1]&gt; 0 0</span></span>
<span id="cb70-8"><a href="#cb70-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 e &lt;dbl [1]&gt; 0 0</span></span>
<span id="cb70-9"><a href="#cb70-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 1 more variable:</span></span>
<span id="cb70-10"><a href="#cb70-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # m[3:4] &lt;dbl&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb71"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb71-1"><a href="#cb71-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df2</span>(df2[[<span class="st">&quot;m&quot;</span>]] <span class="ot">&lt;-</span> df2[[<span class="st">&quot;m&quot;</span>]][<span class="dv">1</span>, , <span class="at">drop =</span> <span class="cn">FALSE</span>])</span>
<span id="cb71-2"><a href="#cb71-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[[&lt;-.data.frame`(`*tmp*`, &quot;m&quot;, value = structure(c(1, 0, 0, : replacement has 1 row, data has 4</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb72"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb72-1"><a href="#cb72-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl2</span>(tbl2[[<span class="st">&quot;m&quot;</span>]] <span class="ot">&lt;-</span> tbl2[[<span class="st">&quot;m&quot;</span>]][<span class="dv">1</span>, , <span class="at">drop =</span> <span class="cn">FALSE</span>])</span>
<span id="cb72-2"><a href="#cb72-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb72-3"><a href="#cb72-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tb$n $c $li m[,1] [,2]</span></span>
<span id="cb72-4"><a href="#cb72-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt; &lt;dbl&gt;</span></span>
<span id="cb72-5"><a href="#cb72-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 1 0</span></span>
<span id="cb72-6"><a href="#cb72-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 1 0</span></span>
<span id="cb72-7"><a href="#cb72-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 1 0</span></span>
<span id="cb72-8"><a href="#cb72-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 1 0</span></span>
<span id="cb72-9"><a href="#cb72-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 1 more variable:</span></span>
<span id="cb72-10"><a href="#cb72-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # m[3:4] &lt;dbl&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p><code>j</code> must be a scalar numeric or a string, and cannot be
<code>NA</code>. If <code>j</code> is OOB, a new column is added on the
right hand side, with name repair if needed.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb73"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb73-1"><a href="#cb73-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="st">&quot;x&quot;</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb73-2"><a href="#cb73-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb73-3"><a href="#cb73-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x</span></span>
<span id="cb73-4"><a href="#cb73-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt;</span></span>
<span id="cb73-5"><a href="#cb73-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 0</span></span>
<span id="cb73-6"><a href="#cb73-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 0</span></span>
<span id="cb73-7"><a href="#cb73-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 0</span></span>
<span id="cb73-8"><a href="#cb73-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 0</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb74"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb74-1"><a href="#cb74-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[[<span class="dv">4</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb74-2"><a href="#cb74-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li V4</span></span>
<span id="cb74-3"><a href="#cb74-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9 0</span></span>
<span id="cb74-4"><a href="#cb74-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 10, 11 0</span></span>
<span id="cb74-5"><a href="#cb74-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14 0</span></span>
<span id="cb74-6"><a href="#cb74-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text 0</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb75"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb75-1"><a href="#cb75-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="dv">4</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb75-2"><a href="#cb75-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb75-3"><a href="#cb75-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li ...4</span></span>
<span id="cb75-4"><a href="#cb75-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt;</span></span>
<span id="cb75-5"><a href="#cb75-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 0</span></span>
<span id="cb75-6"><a href="#cb75-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 0</span></span>
<span id="cb75-7"><a href="#cb75-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 0</span></span>
<span id="cb75-8"><a href="#cb75-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 0</span></span></code></pre></div>
</td>
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<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb76"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb76-1"><a href="#cb76-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[[<span class="dv">5</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb76-2"><a href="#cb76-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in format.data.frame(if</span></span>
<span id="cb76-3"><a href="#cb76-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; (omit) x[seq_len(n0), , drop =</span></span>
<span id="cb76-4"><a href="#cb76-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; FALSE] else x, : corrupt data</span></span>
<span id="cb76-5"><a href="#cb76-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; frame: columns will be truncated or</span></span>
<span id="cb76-6"><a href="#cb76-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; padded with NAs</span></span>
<span id="cb76-7"><a href="#cb76-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li V5</span></span>
<span id="cb76-8"><a href="#cb76-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9 NULL 0</span></span>
<span id="cb76-9"><a href="#cb76-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 10, 11 &lt;NA&gt; 0</span></span>
<span id="cb76-10"><a href="#cb76-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14 &lt;NA&gt; 0</span></span>
<span id="cb76-11"><a href="#cb76-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text &lt;NA&gt; 0</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb77"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb77-1"><a href="#cb77-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="dv">5</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb77-2"><a href="#cb77-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[[&lt;-`:</span></span>
<span id="cb77-3"><a href="#cb77-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t assign to columns beyond the end with non-consecutive locations.</span></span>
<span id="cb77-4"><a href="#cb77-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Input has size 3.</span></span>
<span id="cb77-5"><a href="#cb77-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `5` contains non-consecutive location 5.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<!-- HW: should we permitted oob assignment with numeric j? It's a bit weird to create a column with unknonw column -->
<p><code>df[[j]] &lt;- a</code> replaces the complete column so can
change the type.</p>
<p><code>[[&lt;-</code> supports removing a column by assigning
<code>NULL</code> to it.</p>
<p>Removing a nonexistent column is a no-op.</p>
</div>
<div id="definition-of-xname---a" class="section level3">
<h3>Definition of <code>x$name &lt;- a</code></h3>
<p><code>x$name &lt;- a</code> and <code>x$&quot;name&quot; &lt;- a</code> are
equivalent to <code>x[[&quot;name&quot;]] &lt;- a</code>.<a href="#fn6" class="footnote-ref" id="fnref6"><sup>6</sup></a></p>
<table class="dftbl">
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</td>
<td>
<div class="sourceCode" id="cb78"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb78-1"><a href="#cb78-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl<span class="sc">$</span>n <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb78-2"><a href="#cb78-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb78-3"><a href="#cb78-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb78-4"><a href="#cb78-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb78-5"><a href="#cb78-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 e &lt;dbl [1]&gt;</span></span>
<span id="cb78-6"><a href="#cb78-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 f &lt;int [2]&gt;</span></span>
<span id="cb78-7"><a href="#cb78-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 g &lt;int [3]&gt;</span></span>
<span id="cb78-8"><a href="#cb78-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 h &lt;chr [1]&gt;</span></span></code></pre></div>
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</td>
<td>
<div class="sourceCode" id="cb79"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb79-1"><a href="#cb79-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="st">&quot;n&quot;</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb79-2"><a href="#cb79-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb79-3"><a href="#cb79-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb79-4"><a href="#cb79-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb79-5"><a href="#cb79-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 e &lt;dbl [1]&gt;</span></span>
<span id="cb79-6"><a href="#cb79-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 f &lt;int [2]&gt;</span></span>
<span id="cb79-7"><a href="#cb79-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 g &lt;int [3]&gt;</span></span>
<span id="cb79-8"><a href="#cb79-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p><code>$&lt;-</code> does not perform partial matching.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb80"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb80-1"><a href="#cb80-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl<span class="sc">$</span>l <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb80-2"><a href="#cb80-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb80-3"><a href="#cb80-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li l</span></span>
<span id="cb80-4"><a href="#cb80-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt;</span></span>
<span id="cb80-5"><a href="#cb80-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 0</span></span>
<span id="cb80-6"><a href="#cb80-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 0</span></span>
<span id="cb80-7"><a href="#cb80-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 0</span></span>
<span id="cb80-8"><a href="#cb80-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 0</span></span></code></pre></div>
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<td>
</td>
<td>
<div class="sourceCode" id="cb81"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb81-1"><a href="#cb81-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[[<span class="st">&quot;l&quot;</span>]] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb81-2"><a href="#cb81-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb81-3"><a href="#cb81-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li l</span></span>
<span id="cb81-4"><a href="#cb81-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt;</span></span>
<span id="cb81-5"><a href="#cb81-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 0</span></span>
<span id="cb81-6"><a href="#cb81-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 0</span></span>
<span id="cb81-7"><a href="#cb81-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 0</span></span>
<span id="cb81-8"><a href="#cb81-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 0</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<div id="column-subassignment-xj---a" class="section level2">
<h2>Column subassignment: <code>x[j] &lt;- a</code></h2>
<ul>
<li>If <code>j</code> is missing, its replaced with
<code>seq_along(x)</code></li>
<li>If <code>j</code> is logical vector, its converted to numeric with
<code>seq_along(x)[j]</code>.</li>
</ul>
<div id="a-is-a-list-or-data-frame" class="section level3">
<h3><code>a</code> is a list or data frame</h3>
<p>If <code>inherits(a, &quot;list&quot;)</code> or
<code>inherits(a, &quot;data.frame&quot;)</code> is <code>TRUE</code>, then
<code>x[j] &lt;- a</code> is equivalent to
<code>x[[j[[1]]] &lt;- a[[1]]</code>,
<code>x[[j[[2]]]] &lt;- a[[2]]</code>, …</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb82"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb82-1"><a href="#cb82-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="st">&quot;x&quot;</span>, <span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb82-2"><a href="#cb82-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb82-3"><a href="#cb82-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb82-4"><a href="#cb82-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;chr&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb82-5"><a href="#cb82-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 x 4 &lt;dbl [1]&gt;</span></span>
<span id="cb82-6"><a href="#cb82-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 x 3 &lt;int [2]&gt;</span></span>
<span id="cb82-7"><a href="#cb82-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 x 2 &lt;int [3]&gt;</span></span>
<span id="cb82-8"><a href="#cb82-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 x 1 &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb83"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb83-1"><a href="#cb83-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">c</span>(<span class="st">&quot;li&quot;</span>, <span class="st">&quot;x&quot;</span>, <span class="st">&quot;c&quot;</span>)] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="st">&quot;x&quot;</span>, <span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>, <span class="cn">NULL</span>))</span>
<span id="cb83-2"><a href="#cb83-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb83-3"><a href="#cb83-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n li x</span></span>
<span id="cb83-4"><a href="#cb83-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;int&gt;</span></span>
<span id="cb83-5"><a href="#cb83-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 x 4</span></span>
<span id="cb83-6"><a href="#cb83-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA x 3</span></span>
<span id="cb83-7"><a href="#cb83-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 x 2</span></span>
<span id="cb83-8"><a href="#cb83-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA x 1</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>If <code>length(a)</code> equals 1, then it is recycled to the same
length as <code>j</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb84"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb84-1"><a href="#cb84-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">1</span>))</span>
<span id="cb84-2"><a href="#cb84-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb84-3"><a href="#cb84-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb84-4"><a href="#cb84-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;dbl&gt; &lt;list&gt; </span></span>
<span id="cb84-5"><a href="#cb84-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 1 &lt;dbl [1]&gt;</span></span>
<span id="cb84-6"><a href="#cb84-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 1 &lt;int [2]&gt;</span></span>
<span id="cb84-7"><a href="#cb84-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 1 &lt;int [3]&gt;</span></span>
<span id="cb84-8"><a href="#cb84-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 1 &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb85"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb85-1"><a href="#cb85-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>, <span class="dv">0</span>, <span class="dv">0</span>))</span>
<span id="cb85-2"><a href="#cb85-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb85-3"><a href="#cb85-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 1:2,</span></span>
<span id="cb85-4"><a href="#cb85-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; value = list(0, 0, 0)): provided 3</span></span>
<span id="cb85-5"><a href="#cb85-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; variables to replace 2 variables</span></span>
<span id="cb85-6"><a href="#cb85-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb85-7"><a href="#cb85-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 0 9</span></span>
<span id="cb85-8"><a href="#cb85-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 0 10, 11</span></span>
<span id="cb85-9"><a href="#cb85-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 0 12, 13, 14</span></span>
<span id="cb85-10"><a href="#cb85-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 0 text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb86"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb86-1"><a href="#cb86-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>, <span class="dv">0</span>, <span class="dv">0</span>))</span>
<span id="cb86-2"><a href="#cb86-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb86-3"><a href="#cb86-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t recycle `list(0, 0, 0)` (size 3) to size 2.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb87"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb87-1"><a href="#cb87-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>, <span class="dv">0</span>))</span>
<span id="cb87-2"><a href="#cb87-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb87-3"><a href="#cb87-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 0 0</span></span>
<span id="cb87-4"><a href="#cb87-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 0 0</span></span>
<span id="cb87-5"><a href="#cb87-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 0 0</span></span>
<span id="cb87-6"><a href="#cb87-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 0 0</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb88"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb88-1"><a href="#cb88-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>, <span class="dv">0</span>))</span>
<span id="cb88-2"><a href="#cb88-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb88-3"><a href="#cb88-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t recycle `list(0, 0)` (size 2) to size 3.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>An attempt to update the same column twice gives an error.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb89"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb89-1"><a href="#cb89-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="fu">c</span>(<span class="dv">1</span>, <span class="dv">1</span>)] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">1</span>, <span class="dv">2</span>))</span>
<span id="cb89-2"><a href="#cb89-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-.data.frame`(`*tmp*`, c(1, 1), value = list(1, 2)): duplicate subscripts for columns</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb90"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb90-1"><a href="#cb90-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">c</span>(<span class="dv">1</span>, <span class="dv">1</span>)] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">1</span>, <span class="dv">2</span>))</span>
<span id="cb90-2"><a href="#cb90-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb90-3"><a href="#cb90-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Column index 1 is used</span></span>
<span id="cb90-4"><a href="#cb90-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; more than once for assignment.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>If <code>a</code> contains <code>NULL</code> values, the
corresponding columns are removed <em>after</em> updating (i.e. position
indexes refer to columns before any modifications).</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb91"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb91-1"><a href="#cb91-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="cn">NULL</span>, <span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb91-2"><a href="#cb91-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb91-3"><a href="#cb91-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c li </span></span>
<span id="cb91-4"><a href="#cb91-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb91-5"><a href="#cb91-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 4 &lt;dbl [1]&gt;</span></span>
<span id="cb91-6"><a href="#cb91-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 3 &lt;int [2]&gt;</span></span>
<span id="cb91-7"><a href="#cb91-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 2 &lt;int [3]&gt;</span></span>
<span id="cb91-8"><a href="#cb91-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p><code>NA</code> indexes are not supported.</p>
<p>Just like column updates, <code>[&lt;-</code> supports changing the
type of an existing column.</p>
<p>Appending columns at the end (without gaps) is supported. The name of
new columns is determined by the LHS, the RHS, or by name repair (in
that order of precedence).</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb92"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb92-1"><a href="#cb92-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">c</span>(<span class="st">&quot;x&quot;</span>, <span class="st">&quot;y&quot;</span>)] <span class="ot">&lt;-</span> <span class="fu">tibble</span>(<span class="st">&quot;x&quot;</span>, <span class="at">x =</span> <span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb92-2"><a href="#cb92-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 5</span></span>
<span id="cb92-3"><a href="#cb92-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x y</span></span>
<span id="cb92-4"><a href="#cb92-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;chr&gt; &lt;int&gt;</span></span>
<span id="cb92-5"><a href="#cb92-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; x 4</span></span>
<span id="cb92-6"><a href="#cb92-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; x 3</span></span>
<span id="cb92-7"><a href="#cb92-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; x 2</span></span>
<span id="cb92-8"><a href="#cb92-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; x 1</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb93"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb93-1"><a href="#cb93-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">3</span><span class="sc">:</span><span class="dv">4</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="st">&quot;x&quot;</span>, <span class="at">x =</span> <span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb93-2"><a href="#cb93-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb93-3"><a href="#cb93-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x</span></span>
<span id="cb93-4"><a href="#cb93-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;chr&gt; &lt;int&gt;</span></span>
<span id="cb93-5"><a href="#cb93-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e x 4</span></span>
<span id="cb93-6"><a href="#cb93-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f x 3</span></span>
<span id="cb93-7"><a href="#cb93-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g x 2</span></span>
<span id="cb93-8"><a href="#cb93-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h x 1</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb94"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb94-1"><a href="#cb94-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">4</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb94-2"><a href="#cb94-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li V4</span></span>
<span id="cb94-3"><a href="#cb94-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9 4</span></span>
<span id="cb94-4"><a href="#cb94-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 10, 11 3</span></span>
<span id="cb94-5"><a href="#cb94-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14 2</span></span>
<span id="cb94-6"><a href="#cb94-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text 1</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb95"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb95-1"><a href="#cb95-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">4</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb95-2"><a href="#cb95-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb95-3"><a href="#cb95-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li ...4</span></span>
<span id="cb95-4"><a href="#cb95-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;int&gt;</span></span>
<span id="cb95-5"><a href="#cb95-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 4</span></span>
<span id="cb95-6"><a href="#cb95-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 3</span></span>
<span id="cb95-7"><a href="#cb95-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 2</span></span>
<span id="cb95-8"><a href="#cb95-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 1</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb96"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb96-1"><a href="#cb96-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">5</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb96-2"><a href="#cb96-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-.data.frame`(`*tmp*`, 5, value = list(4:1)): new columns would leave holes after existing columns</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb97"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb97-1"><a href="#cb97-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">5</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>))</span>
<span id="cb97-2"><a href="#cb97-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb97-3"><a href="#cb97-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t assign to columns beyond the end with non-consecutive locations.</span></span>
<span id="cb97-4"><a href="#cb97-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Input has size 3.</span></span>
<span id="cb97-5"><a href="#cb97-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `5` contains non-consecutive location 5.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Tibbles support indexing by a logical matrix, but only for a scalar
RHS, and if all columns updated are compatible with the value
assigned.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb98"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb98-1"><a href="#cb98-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="fu">is.na</span>(df)] <span class="ot">&lt;-</span> <span class="dv">4</span>)</span>
<span id="cb98-2"><a href="#cb98-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb98-3"><a href="#cb98-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb98-4"><a href="#cb98-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 4 f 10, 11</span></span>
<span id="cb98-5"><a href="#cb98-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14</span></span>
<span id="cb98-6"><a href="#cb98-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb99"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb99-1"><a href="#cb99-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">is.na</span>(tbl)] <span class="ot">&lt;-</span> <span class="dv">4</span>)</span>
<span id="cb99-2"><a href="#cb99-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb99-3"><a href="#cb99-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb99-4"><a href="#cb99-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb99-5"><a href="#cb99-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb99-6"><a href="#cb99-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 4 f &lt;int [2]&gt;</span></span>
<span id="cb99-7"><a href="#cb99-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb99-8"><a href="#cb99-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb100"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb100-1"><a href="#cb100-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="fu">is.na</span>(df)] <span class="ot">&lt;-</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>)</span>
<span id="cb100-2"><a href="#cb100-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb100-3"><a href="#cb100-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb100-4"><a href="#cb100-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 f 10, 11</span></span>
<span id="cb100-5"><a href="#cb100-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14</span></span>
<span id="cb100-6"><a href="#cb100-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 2 h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb101"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb101-1"><a href="#cb101-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">is.na</span>(tbl)] <span class="ot">&lt;-</span> <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>)</span>
<span id="cb101-2"><a href="#cb101-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb101-3"><a href="#cb101-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Subscript `is.na(tbl)` is</span></span>
<span id="cb101-4"><a href="#cb101-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; a matrix, the data `1:2` must</span></span>
<span id="cb101-5"><a href="#cb101-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; have size 1.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb102"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb102-1"><a href="#cb102-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="fu">matrix</span>(<span class="fu">c</span>(<span class="fu">rep</span>(<span class="cn">TRUE</span>, <span class="dv">5</span>), <span class="fu">rep</span>(<span class="cn">FALSE</span>, <span class="dv">7</span>)), <span class="at">ncol =</span> <span class="dv">3</span>)] <span class="ot">&lt;-</span> <span class="dv">4</span>)</span>
<span id="cb102-2"><a href="#cb102-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb102-3"><a href="#cb102-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 4 4 9</span></span>
<span id="cb102-4"><a href="#cb102-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 4 f 10, 11</span></span>
<span id="cb102-5"><a href="#cb102-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 4 g 12, 13, 14</span></span>
<span id="cb102-6"><a href="#cb102-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb103"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb103-1"><a href="#cb103-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">matrix</span>(<span class="fu">c</span>(<span class="fu">rep</span>(<span class="cn">TRUE</span>, <span class="dv">5</span>), <span class="fu">rep</span>(<span class="cn">FALSE</span>, <span class="dv">7</span>)), <span class="at">ncol =</span> <span class="dv">3</span>)] <span class="ot">&lt;-</span> <span class="dv">4</span>)</span>
<span id="cb103-2"><a href="#cb103-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb103-3"><a href="#cb103-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `4` must be</span></span>
<span id="cb103-4"><a href="#cb103-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; compatible with existing data.</span></span>
<span id="cb103-5"><a href="#cb103-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `c`.</span></span>
<span id="cb103-6"><a href="#cb103-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb103-7"><a href="#cb103-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;double&gt; to &lt;character&gt;.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="a-is-a-matrix-or-array" class="section level3">
<h3><code>a</code> is a matrix or array</h3>
<p>If <code>is.matrix(a)</code>, then <code>a</code> is coerced to a
data frame with <code>as.data.frame()</code> before assigning. If rows
are assigned, the matrix type must be compatible with all columns. If
<code>is.array(a)</code> and <code>any(dim(a)[-1:-2] != 1)</code>, an
error is thrown.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb104"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb104-1"><a href="#cb104-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">matrix</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">ncol =</span> <span class="dv">2</span>))</span>
<span id="cb104-2"><a href="#cb104-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb104-3"><a href="#cb104-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb104-4"><a href="#cb104-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb104-5"><a href="#cb104-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 8 4 &lt;dbl [1]&gt;</span></span>
<span id="cb104-6"><a href="#cb104-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 7 3 &lt;int [2]&gt;</span></span>
<span id="cb104-7"><a href="#cb104-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 6 2 &lt;int [3]&gt;</span></span>
<span id="cb104-8"><a href="#cb104-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 5 1 &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb105"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb105-1"><a href="#cb105-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">matrix</span>(<span class="dv">6</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">ncol =</span> <span class="dv">2</span>))</span>
<span id="cb105-2"><a href="#cb105-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb105-3"><a href="#cb105-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 6 3 9</span></span>
<span id="cb105-4"><a href="#cb105-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 5 2 10, 11</span></span>
<span id="cb105-5"><a href="#cb105-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 4 1 12, 13, 14</span></span>
<span id="cb105-6"><a href="#cb105-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
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<td>
<div class="sourceCode" id="cb106"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb106-1"><a href="#cb106-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">matrix</span>(<span class="dv">6</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">ncol =</span> <span class="dv">2</span>))</span>
<span id="cb106-2"><a href="#cb106-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb106-3"><a href="#cb106-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `matrix(6:1,</span></span>
<span id="cb106-4"><a href="#cb106-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ncol = 2)` must be compatible</span></span>
<span id="cb106-5"><a href="#cb106-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; with existing data.</span></span>
<span id="cb106-6"><a href="#cb106-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `c`.</span></span>
<span id="cb106-7"><a href="#cb106-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb106-8"><a href="#cb106-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;integer&gt; to &lt;character&gt;.</span></span></code></pre></div>
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<td>
<div class="sourceCode" id="cb107"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb107-1"><a href="#cb107-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">4</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">4</span>, <span class="dv">1</span>, <span class="dv">1</span>)))</span>
<span id="cb107-2"><a href="#cb107-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb107-3"><a href="#cb107-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb107-4"><a href="#cb107-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb107-5"><a href="#cb107-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 4 4 &lt;dbl [1]&gt;</span></span>
<span id="cb107-6"><a href="#cb107-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 3 3 &lt;int [2]&gt;</span></span>
<span id="cb107-7"><a href="#cb107-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 2 2 &lt;int [3]&gt;</span></span>
<span id="cb107-8"><a href="#cb107-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 1 &lt;chr [1]&gt;</span></span></code></pre></div>
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<div class="sourceCode" id="cb108"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb108-1"><a href="#cb108-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">4</span>, <span class="dv">2</span>, <span class="dv">1</span>)))</span>
<span id="cb108-2"><a href="#cb108-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb108-3"><a href="#cb108-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb108-4"><a href="#cb108-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb108-5"><a href="#cb108-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 8 4 &lt;dbl [1]&gt;</span></span>
<span id="cb108-6"><a href="#cb108-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 7 3 &lt;int [2]&gt;</span></span>
<span id="cb108-7"><a href="#cb108-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 6 2 &lt;int [3]&gt;</span></span>
<span id="cb108-8"><a href="#cb108-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 5 1 &lt;chr [1]&gt;</span></span></code></pre></div>
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<div class="sourceCode" id="cb109"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb109-1"><a href="#cb109-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">2</span>, <span class="dv">1</span>, <span class="dv">4</span>)))</span>
<span id="cb109-2"><a href="#cb109-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb109-3"><a href="#cb109-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 8 4 9</span></span>
<span id="cb109-4"><a href="#cb109-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 7 3 10, 11</span></span>
<span id="cb109-5"><a href="#cb109-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 6 2 12, 13, 14</span></span>
<span id="cb109-6"><a href="#cb109-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 5 1 text</span></span></code></pre></div>
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<div class="sourceCode" id="cb110"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb110-1"><a href="#cb110-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">2</span>, <span class="dv">1</span>, <span class="dv">4</span>)))</span>
<span id="cb110-2"><a href="#cb110-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb110-3"><a href="#cb110-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `array(8:1, dim = c(2, 1,</span></span>
<span id="cb110-4"><a href="#cb110-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4))` must be a vector, a bare</span></span>
<span id="cb110-5"><a href="#cb110-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; list, a data frame, a matrix, or</span></span>
<span id="cb110-6"><a href="#cb110-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL.</span></span></code></pre></div>
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<td>
<div class="sourceCode" id="cb111"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb111-1"><a href="#cb111-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">4</span>, <span class="dv">1</span>, <span class="dv">2</span>)))</span>
<span id="cb111-2"><a href="#cb111-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb111-3"><a href="#cb111-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 8 4 9</span></span>
<span id="cb111-4"><a href="#cb111-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 7 3 10, 11</span></span>
<span id="cb111-5"><a href="#cb111-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 6 2 12, 13, 14</span></span>
<span id="cb111-6"><a href="#cb111-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 5 1 text</span></span></code></pre></div>
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<div class="sourceCode" id="cb112"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb112-1"><a href="#cb112-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">array</span>(<span class="dv">8</span><span class="sc">:</span><span class="dv">1</span>, <span class="at">dim =</span> <span class="fu">c</span>(<span class="dv">4</span>, <span class="dv">1</span>, <span class="dv">2</span>)))</span>
<span id="cb112-2"><a href="#cb112-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb112-3"><a href="#cb112-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `array(8:1, dim = c(4, 1,</span></span>
<span id="cb112-4"><a href="#cb112-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2))` must be a vector, a bare</span></span>
<span id="cb112-5"><a href="#cb112-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; list, a data frame, a matrix, or</span></span>
<span id="cb112-6"><a href="#cb112-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL.</span></span></code></pre></div>
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</tbody>
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</div>
<div id="a-is-another-type-of-vector" class="section level3">
<h3><code>a</code> is another type of vector</h3>
<p>If <code>vec_is(a)</code>, then <code>x[j] &lt;- a</code> is
equivalent to <code>x[j] &lt;- list(a)</code>. This is primarily
provided for backward compatibility.</p>
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<td>
<div class="sourceCode" id="cb113"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb113-1"><a href="#cb113-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="dv">0</span>)</span>
<span id="cb113-2"><a href="#cb113-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb113-3"><a href="#cb113-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb113-4"><a href="#cb113-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb113-5"><a href="#cb113-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 e &lt;dbl [1]&gt;</span></span>
<span id="cb113-6"><a href="#cb113-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 f &lt;int [2]&gt;</span></span>
<span id="cb113-7"><a href="#cb113-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 g &lt;int [3]&gt;</span></span>
<span id="cb113-8"><a href="#cb113-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 h &lt;chr [1]&gt;</span></span></code></pre></div>
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</td>
<td>
<div class="sourceCode" id="cb114"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb114-1"><a href="#cb114-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="dv">0</span>))</span>
<span id="cb114-2"><a href="#cb114-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb114-3"><a href="#cb114-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb114-4"><a href="#cb114-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;dbl&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb114-5"><a href="#cb114-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 0 e &lt;dbl [1]&gt;</span></span>
<span id="cb114-6"><a href="#cb114-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 0 f &lt;int [2]&gt;</span></span>
<span id="cb114-7"><a href="#cb114-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 g &lt;int [3]&gt;</span></span>
<span id="cb114-8"><a href="#cb114-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 0 h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
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</tbody>
</table>
<p>Matrices must be wrapped in <code>list()</code> before assignment to
create a matrix column.</p>
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</td>
<td>
<div class="sourceCode" id="cb115"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb115-1"><a href="#cb115-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="fu">matrix</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">8</span>, <span class="at">ncol =</span> <span class="dv">2</span>)))</span>
<span id="cb115-2"><a href="#cb115-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb115-3"><a href="#cb115-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n[,1] [,2] c li </span></span>
<span id="cb115-4"><a href="#cb115-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb115-5"><a href="#cb115-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 5 e &lt;dbl [1]&gt;</span></span>
<span id="cb115-6"><a href="#cb115-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 2 6 f &lt;int [2]&gt;</span></span>
<span id="cb115-7"><a href="#cb115-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 7 g &lt;int [3]&gt;</span></span>
<span id="cb115-8"><a href="#cb115-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 8 h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
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<td>
</td>
<td>
</td>
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<td>
</td>
<td>
<div class="sourceCode" id="cb116"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb116-1"><a href="#cb116-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(<span class="fu">matrix</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">8</span>, <span class="at">ncol =</span> <span class="dv">2</span>)))</span>
<span id="cb116-2"><a href="#cb116-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb116-3"><a href="#cb116-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n[,1] [,2] c[,1] [,2] li </span></span>
<span id="cb116-4"><a href="#cb116-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;int&gt; &lt;int&gt; &lt;int&gt; &lt;list&gt; </span></span>
<span id="cb116-5"><a href="#cb116-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 5 1 5 &lt;dbl [1]&gt;</span></span>
<span id="cb116-6"><a href="#cb116-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 2 6 2 6 &lt;int [2]&gt;</span></span>
<span id="cb116-7"><a href="#cb116-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 7 3 7 &lt;int [3]&gt;</span></span>
<span id="cb116-8"><a href="#cb116-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 4 8 4 8 &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
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</tbody>
</table>
</div>
<div id="a-is-null" class="section level3">
<h3><code>a</code> is <code>NULL</code></h3>
<p>Entire columns can be removed. Specifying <code>i</code> is an
error.</p>
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<td>
<div class="sourceCode" id="cb117"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb117-1"><a href="#cb117-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb117-2"><a href="#cb117-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb117-3"><a href="#cb117-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c li </span></span>
<span id="cb117-4"><a href="#cb117-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb117-5"><a href="#cb117-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb117-6"><a href="#cb117-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 f &lt;int [2]&gt;</span></span>
<span id="cb117-7"><a href="#cb117-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 g &lt;int [3]&gt;</span></span>
<span id="cb117-8"><a href="#cb117-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 h &lt;chr [1]&gt;</span></span></code></pre></div>
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<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb118"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb118-1"><a href="#cb118-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[, <span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb118-2"><a href="#cb118-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 1</span></span>
<span id="cb118-3"><a href="#cb118-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n</span></span>
<span id="cb118-4"><a href="#cb118-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt;</span></span>
<span id="cb118-5"><a href="#cb118-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1</span></span>
<span id="cb118-6"><a href="#cb118-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA</span></span>
<span id="cb118-7"><a href="#cb118-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3</span></span>
<span id="cb118-8"><a href="#cb118-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb119"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb119-1"><a href="#cb119-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span>, <span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb119-2"><a href="#cb119-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in x[[jj]][iseq] &lt;- vjj: replacement has length zero</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb120"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb120-1"><a href="#cb120-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>, <span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb120-2"><a href="#cb120-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb120-3"><a href="#cb120-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `NULL` must be a vector, a</span></span>
<span id="cb120-4"><a href="#cb120-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; bare list, a data frame or a</span></span>
<span id="cb120-5"><a href="#cb120-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; matrix.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="a-is-not-a-vector" class="section level3">
<h3><code>a</code> is not a vector</h3>
<p>Any other type for <code>a</code> is an error. Note that if
<code>is.list(a)</code> is <code>TRUE</code>, but
<code>inherits(a, &quot;list&quot;)</code> is <code>FALSE</code>, then
<code>a</code> is considered to be a scalar. See <code>?vec_is</code>
and <code>?vec_proxy</code> for details.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb121"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb121-1"><a href="#cb121-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span>] <span class="ot">&lt;-</span> mean)</span>
<span id="cb121-2"><a href="#cb121-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in rep(value, length.out = n): attempt to replicate an object of type &#39;closure&#39;</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb122"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb122-1"><a href="#cb122-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> mean)</span>
<span id="cb122-2"><a href="#cb122-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb122-3"><a href="#cb122-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `mean` must be a vector, a</span></span>
<span id="cb122-4"><a href="#cb122-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; bare list, a data frame, a</span></span>
<span id="cb122-5"><a href="#cb122-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; matrix, or NULL.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb123"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb123-1"><a href="#cb123-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="fu">lm</span>(mpg <span class="sc">~</span> wt, <span class="at">data =</span> mtcars))</span>
<span id="cb123-2"><a href="#cb123-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb123-3"><a href="#cb123-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 1, value</span></span>
<span id="cb123-4"><a href="#cb123-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; = structure(list(coefficients =</span></span>
<span id="cb123-5"><a href="#cb123-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c(`(Intercept)` = 37.285126167342,</span></span>
<span id="cb123-6"><a href="#cb123-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; : replacement element 2 has 32 rows</span></span>
<span id="cb123-7"><a href="#cb123-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; to replace 4 rows</span></span>
<span id="cb123-8"><a href="#cb123-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb123-9"><a href="#cb123-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 1, value</span></span>
<span id="cb123-10"><a href="#cb123-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; = structure(list(coefficients =</span></span>
<span id="cb123-11"><a href="#cb123-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c(`(Intercept)` = 37.285126167342,</span></span>
<span id="cb123-12"><a href="#cb123-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; : replacement element 3 has 32 rows</span></span>
<span id="cb123-13"><a href="#cb123-13" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; to replace 4 rows</span></span>
<span id="cb123-14"><a href="#cb123-14" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb123-15"><a href="#cb123-15" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 1, value</span></span>
<span id="cb123-16"><a href="#cb123-16" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; = structure(list(coefficients =</span></span>
<span id="cb123-17"><a href="#cb123-17" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c(`(Intercept)` = 37.285126167342,</span></span>
<span id="cb123-18"><a href="#cb123-18" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; : replacement element 5 has 32 rows</span></span>
<span id="cb123-19"><a href="#cb123-19" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; to replace 4 rows</span></span>
<span id="cb123-20"><a href="#cb123-20" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb123-21"><a href="#cb123-21" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 1, value</span></span>
<span id="cb123-22"><a href="#cb123-22" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; = structure(list(coefficients =</span></span>
<span id="cb123-23"><a href="#cb123-23" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; c(`(Intercept)` = 37.285126167342,</span></span>
<span id="cb123-24"><a href="#cb123-24" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; : replacement element 7 has 5 rows</span></span>
<span id="cb123-25"><a href="#cb123-25" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; to replace 4 rows</span></span>
<span id="cb123-26"><a href="#cb123-26" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-.data.frame`(`*tmp*`, 1, value = structure(list(coefficients = c(`(Intercept)` = 37.285126167342, : replacement element 10 has 3 rows, need 4</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb124"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb124-1"><a href="#cb124-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">1</span>] <span class="ot">&lt;-</span> <span class="fu">lm</span>(mpg <span class="sc">~</span> wt, <span class="at">data =</span> mtcars))</span>
<span id="cb124-2"><a href="#cb124-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb124-3"><a href="#cb124-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `lm(mpg ~ wt, data =</span></span>
<span id="cb124-4"><a href="#cb124-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; mtcars)` must be a vector, a bare</span></span>
<span id="cb124-5"><a href="#cb124-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; list, a data frame, a matrix, or</span></span>
<span id="cb124-6"><a href="#cb124-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; NULL.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<!-- HW: we need better error messages for these cases -->
</div>
</div>
<div id="row-subassignment-xi---list..." class="section level2">
<h2>Row subassignment: <code>x[i, ] &lt;- list(...)</code></h2>
<p><code>x[i, ] &lt;- a</code> is the same as
<code>vec_slice(x[[j_1]], i) &lt;- a[[1]]</code>,
<code>vec_slice(x[[j_2]], i) &lt;- a[[2]]</code>, … .<a href="#fn7" class="footnote-ref" id="fnref7"><sup>7</sup></a></p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb125"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb125-1"><a href="#cb125-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb125-2"><a href="#cb125-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb125-3"><a href="#cb125-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb125-4"><a href="#cb125-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb125-5"><a href="#cb125-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb125-6"><a href="#cb125-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb125-7"><a href="#cb125-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb125-8"><a href="#cb125-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb126"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb126-1"><a href="#cb126-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">c</span>(<span class="cn">FALSE</span>, <span class="cn">TRUE</span>, <span class="cn">TRUE</span>, <span class="cn">FALSE</span>), ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb126-2"><a href="#cb126-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb126-3"><a href="#cb126-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb126-4"><a href="#cb126-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb126-5"><a href="#cb126-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb126-6"><a href="#cb126-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb126-7"><a href="#cb126-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb126-8"><a href="#cb126-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Only values of size one can be recycled.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb127"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb127-1"><a href="#cb127-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb127-2"><a href="#cb127-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb127-3"><a href="#cb127-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb127-4"><a href="#cb127-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb127-5"><a href="#cb127-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb127-6"><a href="#cb127-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb127-7"><a href="#cb127-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb127-8"><a href="#cb127-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb128"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb128-1"><a href="#cb128-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, ] <span class="ot">&lt;-</span> <span class="fu">list</span>(tbl<span class="sc">$</span>n[<span class="dv">1</span>], tbl<span class="sc">$</span>c[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>], tbl<span class="sc">$</span>li[<span class="dv">1</span>]))</span>
<span id="cb128-2"><a href="#cb128-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb128-3"><a href="#cb128-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb128-4"><a href="#cb128-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb128-5"><a href="#cb128-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb128-6"><a href="#cb128-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb128-7"><a href="#cb128-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 f &lt;dbl [1]&gt;</span></span>
<span id="cb128-8"><a href="#cb128-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb129"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb129-1"><a href="#cb129-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">4</span>, ] <span class="ot">&lt;-</span> df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, ])</span>
<span id="cb129-2"><a href="#cb129-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-.data.frame`(`*tmp*`, 2:4, , value = structure(list(n = c(1L, : replacement element 1 has 2 rows, need 3</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb130"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb130-1"><a href="#cb130-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">4</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, ])</span>
<span id="cb130-2"><a href="#cb130-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb130-3"><a href="#cb130-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `tbl[1:2, ]`</span></span>
<span id="cb130-4"><a href="#cb130-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; must be compatible with row</span></span>
<span id="cb130-5"><a href="#cb130-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; subscript `2:4`.</span></span>
<span id="cb130-6"><a href="#cb130-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ 3 rows must be assigned.</span></span>
<span id="cb130-7"><a href="#cb130-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Element 1 of assigned data has 2</span></span>
<span id="cb130-8"><a href="#cb130-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; rows.</span></span>
<span id="cb130-9"><a href="#cb130-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Only vectors of size 1 are</span></span>
<span id="cb130-10"><a href="#cb130-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; recycled.</span></span>
<span id="cb130-11"><a href="#cb130-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vectbl_recycle_rhs_rows()` at ]8;line = 169:col = 6;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:169:6]8;;:</span></span>
<span id="cb130-12"><a href="#cb130-12" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t recycle input of size 2 to size 3.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>For compatibility, only a warning is issued for indexing beyond the
number of rows. Appending rows right at the end of the existing data is
supported, without warning.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb131"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb131-1"><a href="#cb131-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">5</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb131-2"><a href="#cb131-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 5 × 3</span></span>
<span id="cb131-3"><a href="#cb131-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb131-4"><a href="#cb131-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb131-5"><a href="#cb131-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb131-6"><a href="#cb131-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt;</span></span>
<span id="cb131-7"><a href="#cb131-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb131-8"><a href="#cb131-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span>
<span id="cb131-9"><a href="#cb131-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 1 e &lt;dbl [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb132"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb132-1"><a href="#cb132-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">5</span><span class="sc">:</span><span class="dv">7</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb132-2"><a href="#cb132-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 7 × 3</span></span>
<span id="cb132-3"><a href="#cb132-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb132-4"><a href="#cb132-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb132-5"><a href="#cb132-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb132-6"><a href="#cb132-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt;</span></span>
<span id="cb132-7"><a href="#cb132-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb132-8"><a href="#cb132-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span>
<span id="cb132-9"><a href="#cb132-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb132-10"><a href="#cb132-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 6 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb132-11"><a href="#cb132-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 7 1 e &lt;dbl [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb133"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb133-1"><a href="#cb133-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">6</span>, ] <span class="ot">&lt;-</span> df[<span class="dv">1</span>, ])</span>
<span id="cb133-2"><a href="#cb133-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb133-3"><a href="#cb133-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb133-4"><a href="#cb133-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 10, 11</span></span>
<span id="cb133-5"><a href="#cb133-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g 12, 13, 14</span></span>
<span id="cb133-6"><a href="#cb133-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span>
<span id="cb133-7"><a href="#cb133-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 NA &lt;NA&gt; NULL</span></span>
<span id="cb133-8"><a href="#cb133-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 6 1 e 9</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb134"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb134-1"><a href="#cb134-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">6</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb134-2"><a href="#cb134-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb134-3"><a href="#cb134-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t assign to rows beyond the end with non-consecutive locations.</span></span>
<span id="cb134-4"><a href="#cb134-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Input has size 4.</span></span>
<span id="cb134-5"><a href="#cb134-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ✖ Subscript `6` contains non-consecutive location 6.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb135"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb135-1"><a href="#cb135-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="sc">-</span><span class="dv">5</span>, ] <span class="ot">&lt;-</span> df[<span class="dv">1</span>, ])</span>
<span id="cb135-2"><a href="#cb135-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb135-3"><a href="#cb135-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb135-4"><a href="#cb135-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e 9</span></span>
<span id="cb135-5"><a href="#cb135-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e 9</span></span>
<span id="cb135-6"><a href="#cb135-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 e 9</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb136"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb136-1"><a href="#cb136-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="sc">-</span><span class="dv">5</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb136-2"><a href="#cb136-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb136-3"><a href="#cb136-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t negate rows past the end.</span></span>
<span id="cb136-4"><a href="#cb136-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Location 5 doesn&#39;t exist.</span></span>
<span id="cb136-5"><a href="#cb136-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; There are only 4 rows.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb137"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb137-1"><a href="#cb137-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="sc">-</span>(<span class="dv">5</span><span class="sc">:</span><span class="dv">7</span>), ] <span class="ot">&lt;-</span> df[<span class="dv">1</span>, ])</span>
<span id="cb137-2"><a href="#cb137-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb137-3"><a href="#cb137-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb137-4"><a href="#cb137-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e 9</span></span>
<span id="cb137-5"><a href="#cb137-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e 9</span></span>
<span id="cb137-6"><a href="#cb137-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 e 9</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb138"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb138-1"><a href="#cb138-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="sc">-</span>(<span class="dv">5</span><span class="sc">:</span><span class="dv">7</span>), ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb138-2"><a href="#cb138-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb138-3"><a href="#cb138-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t negate rows past the end.</span></span>
<span id="cb138-4"><a href="#cb138-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Locations 5, 6, and 7</span></span>
<span id="cb138-5"><a href="#cb138-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; don&#39;t exist.</span></span>
<span id="cb138-6"><a href="#cb138-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; There are only 4 rows.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb139"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb139-1"><a href="#cb139-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="sc">-</span><span class="dv">6</span>, ] <span class="ot">&lt;-</span> df[<span class="dv">1</span>, ])</span>
<span id="cb139-2"><a href="#cb139-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb139-3"><a href="#cb139-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb139-4"><a href="#cb139-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e 9</span></span>
<span id="cb139-5"><a href="#cb139-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e 9</span></span>
<span id="cb139-6"><a href="#cb139-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 1 e 9</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb140"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb140-1"><a href="#cb140-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="sc">-</span><span class="dv">6</span>, ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb140-2"><a href="#cb140-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb140-3"><a href="#cb140-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t negate rows past the end.</span></span>
<span id="cb140-4"><a href="#cb140-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Location 6 doesn&#39;t exist.</span></span>
<span id="cb140-5"><a href="#cb140-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; There are only 4 rows.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>For compatibility, <code>i</code> can also be a character vector
containing positive numbers.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb141"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb141-1"><a href="#cb141-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="fu">as.character</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">3</span>), ] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span>, ])</span>
<span id="cb141-2"><a href="#cb141-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb141-3"><a href="#cb141-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb141-4"><a href="#cb141-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb141-5"><a href="#cb141-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb141-6"><a href="#cb141-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb141-7"><a href="#cb141-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb141-8"><a href="#cb141-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="row-and-column-subassignment" class="section level2">
<h2>Row and column subassignment</h2>
<div id="definition-of-xi-j---a" class="section level3">
<h3>Definition of <code>x[i, j] &lt;- a</code></h3>
<p><code>x[i, j] &lt;- a</code> is equivalent to
<code>x[i, ][j] &lt;- a</code>.<a href="#fn8" class="footnote-ref" id="fnref8"><sup>8</sup></a></p>
<p>Subassignment to <code>x[i, j]</code> is stricter for tibbles than
for data frames. <code>x[i, j] &lt;- a</code> cant change the data type
of existing columns.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb142"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb142-1"><a href="#cb142-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span>] <span class="ot">&lt;-</span> df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">2</span>])</span>
<span id="cb142-2"><a href="#cb142-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb142-3"><a href="#cb142-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb142-4"><a href="#cb142-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 e f 10, 11</span></span>
<span id="cb142-5"><a href="#cb142-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 f g 12, 13, 14</span></span>
<span id="cb142-6"><a href="#cb142-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 &lt;NA&gt; h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb143"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb143-1"><a href="#cb143-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span>] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">2</span>])</span>
<span id="cb143-2"><a href="#cb143-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb143-3"><a href="#cb143-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `tbl[1:2,</span></span>
<span id="cb143-4"><a href="#cb143-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2]` must be compatible with</span></span>
<span id="cb143-5"><a href="#cb143-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; existing data.</span></span>
<span id="cb143-6"><a href="#cb143-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `n`.</span></span>
<span id="cb143-7"><a href="#cb143-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb143-8"><a href="#cb143-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;character&gt; to &lt;integer&gt;.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb144"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb144-1"><a href="#cb144-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">2</span>] <span class="ot">&lt;-</span> df[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">3</span>])</span>
<span id="cb144-2"><a href="#cb144-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb144-3"><a href="#cb144-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 2:3, 2,</span></span>
<span id="cb144-4"><a href="#cb144-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; value = list(9, 10:11)): provided 2</span></span>
<span id="cb144-5"><a href="#cb144-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; variables to replace 1 variables</span></span>
<span id="cb144-6"><a href="#cb144-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb144-7"><a href="#cb144-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb144-8"><a href="#cb144-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA 9 10, 11</span></span>
<span id="cb144-9"><a href="#cb144-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 9 12, 13, 14</span></span>
<span id="cb144-10"><a href="#cb144-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb145"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb145-1"><a href="#cb145-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">2</span>] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">3</span>])</span>
<span id="cb145-2"><a href="#cb145-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb145-3"><a href="#cb145-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `tbl[1:2,</span></span>
<span id="cb145-4"><a href="#cb145-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3]` must be compatible with</span></span>
<span id="cb145-5"><a href="#cb145-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; existing data.</span></span>
<span id="cb145-6"><a href="#cb145-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `c`.</span></span>
<span id="cb145-7"><a href="#cb145-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb145-8"><a href="#cb145-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;list&gt; to &lt;character&gt;.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb146"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb146-1"><a href="#cb146-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">3</span>] <span class="ot">&lt;-</span> df2[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">1</span>])</span>
<span id="cb146-2"><a href="#cb146-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in</span></span>
<span id="cb146-3"><a href="#cb146-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; `[&lt;-.data.frame`(`*tmp*`, 2:3, 3,</span></span>
<span id="cb146-4"><a href="#cb146-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; value = structure(list(n = c(1L, :</span></span>
<span id="cb146-5"><a href="#cb146-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; provided 3 variables to replace 1</span></span>
<span id="cb146-6"><a href="#cb146-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; variables</span></span>
<span id="cb146-7"><a href="#cb146-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb146-8"><a href="#cb146-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb146-9"><a href="#cb146-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f 1</span></span>
<span id="cb146-10"><a href="#cb146-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g NA</span></span>
<span id="cb146-11"><a href="#cb146-11" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb147"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb147-1"><a href="#cb147-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">3</span>] <span class="ot">&lt;-</span> tbl2[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">1</span>])</span>
<span id="cb147-2"><a href="#cb147-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb147-3"><a href="#cb147-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `tbl2[1:2,</span></span>
<span id="cb147-4"><a href="#cb147-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1]` must be compatible with</span></span>
<span id="cb147-5"><a href="#cb147-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; existing data.</span></span>
<span id="cb147-6"><a href="#cb147-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `li`.</span></span>
<span id="cb147-7"><a href="#cb147-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb147-8"><a href="#cb147-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;tbl_df&gt; to &lt;list&gt;.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb148"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb148-1"><a href="#cb148-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df2</span>(df2[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span>] <span class="ot">&lt;-</span> df2[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">2</span>])</span>
<span id="cb148-2"><a href="#cb148-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Warning in matrix(value, n, p):</span></span>
<span id="cb148-3"><a href="#cb148-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; data length [8] is not a</span></span>
<span id="cb148-4"><a href="#cb148-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; sub-multiple or multiple of the</span></span>
<span id="cb148-5"><a href="#cb148-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; number of columns [3]</span></span>
<span id="cb148-6"><a href="#cb148-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tb.n tb.c tb.li m.1 m.2 m.3 m.4</span></span>
<span id="cb148-7"><a href="#cb148-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9 1 0 0 0</span></span>
<span id="cb148-8"><a href="#cb148-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 0 0 0 1 0 0</span></span>
<span id="cb148-9"><a href="#cb148-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 0 1 0 0 0 1 0</span></span>
<span id="cb148-10"><a href="#cb148-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text 0 0 0 1</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb149"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb149-1"><a href="#cb149-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl2</span>(tbl2[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">1</span>] <span class="ot">&lt;-</span> tbl2[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">2</span>])</span>
<span id="cb149-2"><a href="#cb149-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb149-3"><a href="#cb149-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Assigned data `tbl2[1:2,</span></span>
<span id="cb149-4"><a href="#cb149-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2]` must be compatible with</span></span>
<span id="cb149-5"><a href="#cb149-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; existing data.</span></span>
<span id="cb149-6"><a href="#cb149-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error occurred for column `tb`.</span></span>
<span id="cb149-7"><a href="#cb149-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Caused by error in `vec_assign()` at ]8;line = 193:col = 2;file:///private/var/folders/dj/yhk9rkx97wn_ykqtnmk18xvc0000gn/T/RtmpECx3vm/Rbuild51ca1b126fa/tibble/R/subassign-backend.Rtibble/R/subassign-backend.R:193:2]8;;:</span></span>
<span id="cb149-8"><a href="#cb149-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! Can&#39;t convert &lt;double[,4]&gt; to &lt;tbl_df&gt;.</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb150"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb150-1"><a href="#cb150-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl2</span>(tbl2[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">2</span>] <span class="ot">&lt;-</span> tbl[<span class="dv">1</span><span class="sc">:</span><span class="dv">2</span>, <span class="dv">1</span>])</span>
<span id="cb150-2"><a href="#cb150-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 2</span></span>
<span id="cb150-3"><a href="#cb150-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; tb$n $c $li m[,1] [,2]</span></span>
<span id="cb150-4"><a href="#cb150-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt; &lt;dbl&gt;</span></span>
<span id="cb150-5"><a href="#cb150-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; 1 0</span></span>
<span id="cb150-6"><a href="#cb150-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 1 1</span></span>
<span id="cb150-7"><a href="#cb150-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; NA NA</span></span>
<span id="cb150-8"><a href="#cb150-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; 0 0</span></span>
<span id="cb150-9"><a href="#cb150-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # … with 1 more variable:</span></span>
<span id="cb150-10"><a href="#cb150-10" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # m[3:4] &lt;dbl&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>A notable exception is the population of a column full of
<code>NA</code> (which is of type <code>logical</code>), or the use of
<code>NA</code> on the right-hand side of the assignment.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb151"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb151-1"><a href="#cb151-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>({tbl<span class="sc">$</span>x <span class="ot">&lt;-</span> <span class="cn">NA</span>; tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;x&quot;</span>] <span class="ot">&lt;-</span> <span class="dv">3</span><span class="sc">:</span><span class="dv">2</span>})</span>
<span id="cb151-2"><a href="#cb151-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb151-3"><a href="#cb151-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x</span></span>
<span id="cb151-4"><a href="#cb151-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;int&gt;</span></span>
<span id="cb151-5"><a href="#cb151-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; NA</span></span>
<span id="cb151-6"><a href="#cb151-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 3</span></span>
<span id="cb151-7"><a href="#cb151-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 2</span></span>
<span id="cb151-8"><a href="#cb151-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb152"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb152-1"><a href="#cb152-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>({df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="cn">NA</span>})</span>
<span id="cb152-2"><a href="#cb152-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb152-3"><a href="#cb152-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb152-4"><a href="#cb152-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA &lt;NA&gt; NA</span></span>
<span id="cb152-5"><a href="#cb152-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 &lt;NA&gt; NA</span></span>
<span id="cb152-6"><a href="#cb152-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb153"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb153-1"><a href="#cb153-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>({tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>] <span class="ot">&lt;-</span> <span class="cn">NA</span>})</span>
<span id="cb153-2"><a href="#cb153-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb153-3"><a href="#cb153-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb153-4"><a href="#cb153-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb153-5"><a href="#cb153-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb153-6"><a href="#cb153-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA &lt;NA&gt; &lt;NULL&gt; </span></span>
<span id="cb153-7"><a href="#cb153-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 &lt;NA&gt; &lt;NULL&gt; </span></span>
<span id="cb153-8"><a href="#cb153-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>For programming, it is always safer (and faster) to use the correct
type of <code>NA</code> to initialize columns.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb154"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb154-1"><a href="#cb154-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>({tbl<span class="sc">$</span>x <span class="ot">&lt;-</span> <span class="cn">NA_integer_</span>; tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;x&quot;</span>] <span class="ot">&lt;-</span> <span class="dv">3</span><span class="sc">:</span><span class="dv">2</span>})</span>
<span id="cb154-2"><a href="#cb154-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb154-3"><a href="#cb154-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x</span></span>
<span id="cb154-4"><a href="#cb154-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;int&gt;</span></span>
<span id="cb154-5"><a href="#cb154-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; NA</span></span>
<span id="cb154-6"><a href="#cb154-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 3</span></span>
<span id="cb154-7"><a href="#cb154-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 2</span></span>
<span id="cb154-8"><a href="#cb154-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; NA</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>For new columns, <code>x[i, j] &lt;- a</code> fills the unassigned
rows with <code>NA</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb155"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb155-1"><a href="#cb155-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;n&quot;</span>] <span class="ot">&lt;-</span> <span class="dv">1</span>)</span>
<span id="cb155-2"><a href="#cb155-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li</span></span>
<span id="cb155-3"><a href="#cb155-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e 9</span></span>
<span id="cb155-4"><a href="#cb155-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 f 10, 11</span></span>
<span id="cb155-5"><a href="#cb155-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 g 12, 13, 14</span></span>
<span id="cb155-6"><a href="#cb155-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h text</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb156"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb156-1"><a href="#cb156-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;n&quot;</span>] <span class="ot">&lt;-</span> <span class="dv">1</span>)</span>
<span id="cb156-2"><a href="#cb156-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 3</span></span>
<span id="cb156-3"><a href="#cb156-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb156-4"><a href="#cb156-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb156-5"><a href="#cb156-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb156-6"><a href="#cb156-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 1 f &lt;int [2]&gt;</span></span>
<span id="cb156-7"><a href="#cb156-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 1 g &lt;int [3]&gt;</span></span>
<span id="cb156-8"><a href="#cb156-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb157"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb157-1"><a href="#cb157-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;x&quot;</span>] <span class="ot">&lt;-</span> <span class="dv">1</span>)</span>
<span id="cb157-2"><a href="#cb157-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 4 × 4</span></span>
<span id="cb157-3"><a href="#cb157-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li x</span></span>
<span id="cb157-4"><a href="#cb157-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; &lt;dbl&gt;</span></span>
<span id="cb157-5"><a href="#cb157-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt; NA</span></span>
<span id="cb157-6"><a href="#cb157-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt; 1</span></span>
<span id="cb157-7"><a href="#cb157-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt; 1</span></span>
<span id="cb157-8"><a href="#cb157-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt; NA</span></span></code></pre></div>
</td>
</tr>
<tr style="vertical-align:top">
<td>
<div class="sourceCode" id="cb158"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb158-1"><a href="#cb158-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_df</span>(df[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;n&quot;</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb158-2"><a href="#cb158-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in x[[jj]][iseq] &lt;- vjj: replacement has length zero</span></span></code></pre></div>
</td>
<td>
<div class="sourceCode" id="cb159"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb159-1"><a href="#cb159-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">2</span><span class="sc">:</span><span class="dv">3</span>, <span class="st">&quot;n&quot;</span>] <span class="ot">&lt;-</span> <span class="cn">NULL</span>)</span>
<span id="cb159-2"><a href="#cb159-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; Error in `[&lt;-`:</span></span>
<span id="cb159-3"><a href="#cb159-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; ! `NULL` must be a vector, a</span></span>
<span id="cb159-4"><a href="#cb159-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; bare list, a data frame or a</span></span>
<span id="cb159-5"><a href="#cb159-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; matrix.</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
<p>Likewise, for new rows, <code>x[i, j] &lt;- a</code> fills the
unassigned columns with <code>NA</code>.</p>
<table class="dftbl">
<tbody>
<tr style="vertical-align:top">
<td>
</td>
<td>
<div class="sourceCode" id="cb160"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb160-1"><a href="#cb160-1" aria-hidden="true" tabindex="-1"></a><span class="fu">with_tbl</span>(tbl[<span class="dv">5</span>, <span class="st">&quot;n&quot;</span>] <span class="ot">&lt;-</span> <span class="fu">list</span>(0L))</span>
<span id="cb160-2"><a href="#cb160-2" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; # A tibble: 5 × 3</span></span>
<span id="cb160-3"><a href="#cb160-3" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; n c li </span></span>
<span id="cb160-4"><a href="#cb160-4" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; &lt;int&gt; &lt;chr&gt; &lt;list&gt; </span></span>
<span id="cb160-5"><a href="#cb160-5" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 1 1 e &lt;dbl [1]&gt;</span></span>
<span id="cb160-6"><a href="#cb160-6" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 2 NA f &lt;int [2]&gt;</span></span>
<span id="cb160-7"><a href="#cb160-7" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 3 3 g &lt;int [3]&gt;</span></span>
<span id="cb160-8"><a href="#cb160-8" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 4 NA h &lt;chr [1]&gt;</span></span>
<span id="cb160-9"><a href="#cb160-9" aria-hidden="true" tabindex="-1"></a><span class="co">#&gt; 5 0 &lt;NA&gt; &lt;NULL&gt;</span></span></code></pre></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="definition-of-xi-j---a-1" class="section level3">
<h3>Definition of <code>x[[i, j]] &lt;- a</code></h3>
<p><code>i</code> must be a numeric vector of length 1.
<code>x[[i, j]] &lt;- a</code> is equivalent to
<code>x[i, ][[j]] &lt;- a</code>.<a href="#fn9" class="footnote-ref" id="fnref9"><sup>9</sup></a></p>
<p>NB: <code>vec_size(a)</code> must equal 1. Unlike
<code>x[i, ] &lt;-</code>, <code>x[[i, ]] &lt;-</code> is not valid.</p>
</div>
</div>
<div class="footnotes footnotes-end-of-document">
<hr />
<ol>
<li id="fn1"><p><code>x[j][[jj]]</code> is equal to
<code>x[[ j[[jj]] ]]</code>, in particular <code>x[j][[1]]</code> is
equal to <code>x[[j]]</code> for scalar numeric or integer
<code>j</code>.<a href="#fnref1" class="footnote-back">↩︎</a></p></li>
<li id="fn2"><p>Row subsetting <code>x[i, ]</code> is not defined in
terms of <code>x[[j]][i]</code> because that definition does not
generalise to matrix and data frame columns. For efficiency and backward
compatibility, <code>i</code> is converted to an integer vector by
<code>vec_as_index(i, nrow(x))</code> first.<a href="#fnref2" class="footnote-back">↩︎</a></p></li>
<li id="fn3"><p><code>x[,]</code> is equivalent to <code>x[]</code>
because <code>x[, j]</code> is equivalent to <code>x[j]</code>.<a href="#fnref3" class="footnote-back">↩︎</a></p></li>
<li id="fn4"><p>A more efficient implementation of <code>x[i, j]</code>
would forward to <code>x[j][i, ]</code>.<a href="#fnref4" class="footnote-back">↩︎</a></p></li>
<li id="fn5"><p>Cell subsetting <code>x[[i, j]]</code> is not defined in
terms of <code>x[[j]][[i]]</code> because that definition does not
generalise to list, matrix and data frame columns. A more efficient
implementation of <code>x[[i, j]]</code> would check that <code>j</code>
is a scalar and forward to <code>x[i, j][[1]]</code>.<a href="#fnref5" class="footnote-back">↩︎</a></p></li>
<li id="fn6"><p><code>$</code> behaves almost completely symmetrically
to <code>[[</code> when comparing subsetting and subassignment.<a href="#fnref6" class="footnote-back">↩︎</a></p></li>
<li id="fn7"><p><code>x[i, ]</code> is symmetrical for subset and
subassignment.<a href="#fnref7" class="footnote-back">↩︎</a></p></li>
<li id="fn8"><p><code>x[i, j]</code> is symmetrical for subsetting and
subassignment. A more efficient implementation of
<code>x[i, j] &lt;- a</code> would forward to
<code>x[j][i, ] &lt;- a</code>.<a href="#fnref8" class="footnote-back">↩︎</a></p></li>
<li id="fn9"><p><code>x[[i, j]]</code> is symmetrical for subsetting and
subassignment. An efficient implementation would check that
<code>i</code> and <code>j</code> are scalar and forward to
<code>x[i, j][[1]] &lt;- a</code>.<a href="#fnref9" class="footnote-back">↩︎</a></p></li>
</ol>
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