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 <!-- Generated by pkgdown: do not edit by hand --><html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta charset="utf-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><title>Experimental Arrow encoded arrays as R vectors — as_nanoarrow_vctr • nanoarrow</title><script src="../deps/jquery-3.6.0/jquery-3.6.0.min.js"></script><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><link href="../deps/bootstrap-5.3.1/bootstrap.min.css" rel="stylesheet"><script src="../deps/bootstrap-5.3.1/bootstrap.bundle.min.js"></script><link href="../deps/font-awesome-6.4.2/css/all.min.css" rel="stylesheet"><link href="../deps/font-awesome-6.4.2/css/v4-shims.min.css" rel="stylesheet"><script src="../deps/headroom-0.11.0/headroom.min.js"></script><script src="../deps/headroom-0.11.0/jQuery.headroom.min.js"></script><script src="../deps/bootstrap-toc-1.0.1/bootstrap-toc.min.js"></script><script src="../deps/clipboard.js-2.0.11/clipboard.min.js"></script><script src="../deps/search-1.0.0/autocomplete.jquery.min.js"></script><script src="../deps/search-1.0.0/fuse.min.js"></script><script src="../deps/search-1.0.0/mark.min.js"></script><!-- pkgdown --><script src="../pkgdown.js"></script><meta property="og:title" content="Experimental Arrow encoded arrays as R vectors — as_nanoarrow_vctr"><meta name="description" content="This experimental vctr class allows zero or more Arrow arrays to
 present as an R vector without converting them. This is useful for arrays
 with types that do not have a non-lossy R equivalent, and helps provide an
 intermediary object type where the default conversion is prohibitively
 expensive (e.g., a nested list of data frames). These objects will not
 survive many vctr transformations; however, they can be sliced without
 copying the underlying arrays."><meta property="og:description" content="This experimental vctr class allows zero or more Arrow arrays to
 present as an R vector without converting them. This is useful for arrays
 with types that do not have a non-lossy R equivalent, and helps provide an
 intermediary object type where the default conversion is prohibitively
 expensive (e.g., a nested list of data frames). These objects will not
 survive many vctr transformations; however, they can be sliced without
 copying the underlying arrays."></head><body>
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       <h1>Experimental Arrow encoded arrays as R vectors</h1>
       <small class="dont-index">Source: <a href="https://github.com/apache/arrow-nanoarrow/blob/main/r/R/vctr.R" class="external-link"><code>R/vctr.R</code></a></small>
       <div class="d-none name"><code>as_nanoarrow_vctr.Rd</code></div>
     </div>

     <div class="ref-description section level2">
     <p>This experimental vctr class allows zero or more Arrow arrays to
 present as an R vector without converting them. This is useful for arrays
 with types that do not have a non-lossy R equivalent, and helps provide an
 intermediary object type where the default conversion is prohibitively
 expensive (e.g., a nested list of data frames). These objects will not
 survive many vctr transformations; however, they can be sliced without
 copying the underlying arrays.</p>
     </div>

     <div class="section level2">
     <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
     <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">as_nanoarrow_vctr</span><span class="op">(</span><span class="va">x</span>, <span class="va">...</span>, schema <span class="op">=</span> <span class="cn">NULL</span>, subclass <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="op">)</span><span class="op">)</span></span>
 <span></span>
 <span><span class="fu">nanoarrow_vctr</span><span class="op">(</span>schema <span class="op">=</span> <span class="cn">NULL</span>, subclass <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
     </div>

     <div class="section level2">
     <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


 <dl><dt id="arg-x">x<a class="anchor" aria-label="anchor" href="#arg-x"></a></dt>
 <dd><p>An object that works with <code><a href="as_nanoarrow_array_stream.html">as_nanoarrow_array_stream()</a></code>.</p></dd>


 <dt id="arg--">...<a class="anchor" aria-label="anchor" href="#arg--"></a></dt>
 <dd><p>Passed to <code><a href="as_nanoarrow_array_stream.html">as_nanoarrow_array_stream()</a></code></p></dd>


 <dt id="arg-schema">schema<a class="anchor" aria-label="anchor" href="#arg-schema"></a></dt>
 <dd><p>An optional <code>schema</code></p></dd>


 <dt id="arg-subclass">subclass<a class="anchor" aria-label="anchor" href="#arg-subclass"></a></dt>
 <dd><p>An optional subclass of nanoarrow_vctr to prepend to the
 final class name.</p></dd>

 </dl></div>
     <div class="section level2">
     <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
     <p>A vctr of class 'nanoarrow_vctr'</p>
     </div>
     <div class="section level2">
     <h2 id="details">Details<a class="anchor" aria-label="anchor" href="#details"></a></h2>
     <p>The nanoarrow_vctr is currently implemented similarly to <code><a href="https://rdrr.io/r/base/factor.html" class="external-link">factor()</a></code>: its
 storage type is an <code><a href="https://rdrr.io/r/base/integer.html" class="external-link">integer()</a></code> that is a sequence along the total length
 of the vctr and there are attributes that are required to resolve these
 indices to an array + offset. Sequences typically have a very compact
 representation in recent versions of R such that this has a cheap storage
 footprint even for large arrays. The attributes are currently:</p><ul><li><p><code>schema</code>: The <a href="as_nanoarrow_schema.html">nanoarrow_schema</a> shared by each chunk.</p></li>
 <li><p><code>chunks</code>: A <code><a href="https://rdrr.io/r/base/list.html" class="external-link">list()</a></code> of <code>nanoarrow_array</code>.</p></li>
 <li><p><code>offsets</code>: An <code><a href="https://rdrr.io/r/base/integer.html" class="external-link">integer()</a></code> vector beginning with <code>0</code> and followed by the
 cumulative length of each chunk. This allows the chunk index + offset
 to be resolved from a logical index with <code>log(n)</code> complexity.</p></li>
 </ul><p>This implementation is preliminary and may change; however, the result of
 <code>as_nanoarrow_array_stream(some_vctr[begin:end])</code> should remain stable.</p>
     </div>

     <div class="section level2">
     <h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2>
     <div class="sourceCode"><pre class="sourceCode r"><code><span class="r-in"><span><span class="va">array</span> <span class="op">&lt;-</span> <span class="fu"><a href="as_nanoarrow_array.html">as_nanoarrow_array</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">5</span><span class="op">)</span></span></span>
 <span class="r-in"><span><span class="fu">as_nanoarrow_vctr</span><span class="op">(</span><span class="va">array</span><span class="op">)</span></span></span>
 <span class="r-out co"><span class="r-pr">#&gt;</span> &lt;nanoarrow_vctr int32[5]&gt;</span>
 <span class="r-out co"><span class="r-pr">#&gt;</span> [1] 1 2 3 4 5</span>
 <span class="r-in"><span></span></span>
 </code></pre></div>
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	<!-- Generated by pkgdown: do not edit by hand --><html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta charset="utf-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><title>Experimental Arrow encoded arrays as R vectors — as_nanoarrow_vctr • nanoarrow</title><script src="../deps/jquery-3.6.0/jquery-3.6.0.min.js"></script><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><link href="../deps/bootstrap-5.3.1/bootstrap.min.css" rel="stylesheet"><script src="../deps/bootstrap-5.3.1/bootstrap.bundle.min.js"></script><link href="../deps/font-awesome-6.4.2/css/all.min.css" rel="stylesheet"><link href="../deps/font-awesome-6.4.2/css/v4-shims.min.css" rel="stylesheet"><script src="../deps/headroom-0.11.0/headroom.min.js"></script><script src="../deps/headroom-0.11.0/jQuery.headroom.min.js"></script><script src="../deps/bootstrap-toc-1.0.1/bootstrap-toc.min.js"></script><script src="../deps/clipboard.js-2.0.11/clipboard.min.js"></script><script src="../deps/search-1.0.0/autocomplete.jquery.min.js"></script><script src="../deps/search-1.0.0/fuse.min.js"></script><script src="../deps/search-1.0.0/mark.min.js"></script><!-- pkgdown --><script src="../pkgdown.js"></script><meta property="og:title" content="Experimental Arrow encoded arrays as R vectors — as_nanoarrow_vctr"><meta name="description" content="This experimental vctr class allows zero or more Arrow arrays to
	present as an R vector without converting them. This is useful for arrays
	with types that do not have a non-lossy R equivalent, and helps provide an
	intermediary object type where the default conversion is prohibitively
	expensive (e.g., a nested list of data frames). These objects will not
	survive many vctr transformations; however, they can be sliced without
	copying the underlying arrays."><meta property="og:description" content="This experimental vctr class allows zero or more Arrow arrays to
	present as an R vector without converting them. This is useful for arrays
	with types that do not have a non-lossy R equivalent, and helps provide an
	intermediary object type where the default conversion is prohibitively
	expensive (e.g., a nested list of data frames). These objects will not
	survive many vctr transformations; however, they can be sliced without
	copying the underlying arrays."></head><body>
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	<h1>Experimental Arrow encoded arrays as R vectors</h1>
	<small class="dont-index">Source: <a href="https://github.com/apache/arrow-nanoarrow/blob/main/r/R/vctr.R" class="external-link"><code>R/vctr.R</code></a></small>
	<div class="d-none name"><code>as_nanoarrow_vctr.Rd</code></div>
	</div>

	<div class="ref-description section level2">
	<p>This experimental vctr class allows zero or more Arrow arrays to
	present as an R vector without converting them. This is useful for arrays
	with types that do not have a non-lossy R equivalent, and helps provide an
	intermediary object type where the default conversion is prohibitively
	expensive (e.g., a nested list of data frames). These objects will not
	survive many vctr transformations; however, they can be sliced without
	copying the underlying arrays.</p>
	</div>

	<div class="section level2">
	<h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
	<div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">as_nanoarrow_vctr</span><span class="op">(</span><span class="va">x</span>, <span class="va">...</span>, schema <span class="op">=</span> <span class="cn">NULL</span>, subclass <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="op">)</span><span class="op">)</span></span>
	<span></span>
	<span><span class="fu">nanoarrow_vctr</span><span class="op">(</span>schema <span class="op">=</span> <span class="cn">NULL</span>, subclass <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
	</div>

	<div class="section level2">
	<h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


	<dl><dt id="arg-x">x<a class="anchor" aria-label="anchor" href="#arg-x"></a></dt>
	<dd><p>An object that works with <code><a href="as_nanoarrow_array_stream.html">as_nanoarrow_array_stream()</a></code>.</p></dd>


	<dt id="arg--">...<a class="anchor" aria-label="anchor" href="#arg--"></a></dt>
	<dd><p>Passed to <code><a href="as_nanoarrow_array_stream.html">as_nanoarrow_array_stream()</a></code></p></dd>


	<dt id="arg-schema">schema<a class="anchor" aria-label="anchor" href="#arg-schema"></a></dt>
	<dd><p>An optional <code>schema</code></p></dd>


	<dt id="arg-subclass">subclass<a class="anchor" aria-label="anchor" href="#arg-subclass"></a></dt>
	<dd><p>An optional subclass of nanoarrow_vctr to prepend to the
	final class name.</p></dd>

	</dl></div>
	<div class="section level2">
	<h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
	<p>A vctr of class 'nanoarrow_vctr'</p>
	</div>
	<div class="section level2">
	<h2 id="details">Details<a class="anchor" aria-label="anchor" href="#details"></a></h2>
	<p>The nanoarrow_vctr is currently implemented similarly to <code><a href="https://rdrr.io/r/base/factor.html" class="external-link">factor()</a></code>: its
	storage type is an <code><a href="https://rdrr.io/r/base/integer.html" class="external-link">integer()</a></code> that is a sequence along the total length
	of the vctr and there are attributes that are required to resolve these
	indices to an array + offset. Sequences typically have a very compact
	representation in recent versions of R such that this has a cheap storage
	footprint even for large arrays. The attributes are currently:</p><ul><li><p><code>schema</code>: The <a href="as_nanoarrow_schema.html">nanoarrow_schema</a> shared by each chunk.</p></li>
	<li><p><code>chunks</code>: A <code><a href="https://rdrr.io/r/base/list.html" class="external-link">list()</a></code> of <code>nanoarrow_array</code>.</p></li>
	<li><p><code>offsets</code>: An <code><a href="https://rdrr.io/r/base/integer.html" class="external-link">integer()</a></code> vector beginning with <code>0</code> and followed by the
	cumulative length of each chunk. This allows the chunk index + offset
	to be resolved from a logical index with <code>log(n)</code> complexity.</p></li>
	</ul><p>This implementation is preliminary and may change; however, the result of
	<code>as_nanoarrow_array_stream(some_vctr[begin:end])</code> should remain stable.</p>
	</div>

	<div class="section level2">
	<h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2>
	<div class="sourceCode"><pre class="sourceCode r"><code><span class="r-in"><span><span class="va">array</span> <span class="op"><-</span> <span class="fu"><a href="as_nanoarrow_array.html">as_nanoarrow_array</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">5</span><span class="op">)</span></span></span>
	<span class="r-in"><span><span class="fu">as_nanoarrow_vctr</span><span class="op">(</span><span class="va">array</span><span class="op">)</span></span></span>
	<span class="r-out co"><span class="r-pr">#></span> <nanoarrow_vctr int32[5]></span>
	<span class="r-out co"><span class="r-pr">#></span> [1] 1 2 3 4 5</span>
	<span class="r-in"><span></span></span>
	</code></pre></div>
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