| <!DOCTYPE html> |
| <!-- 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"><meta name="description" content="An Array is an immutable data array with some logical type |
| and some length. Most logical types are contained in the base |
| Array class; there are also subclasses for DictionaryArray, ListArray, |
| and StructArray."><title>Arrow Arrays — array • Arrow R Package</title><!-- favicons --><link rel="icon" type="image/png" sizes="16x16" href="../favicon-16x16.png"><link rel="icon" type="image/png" sizes="32x32" href="../favicon-32x32.png"><link rel="apple-touch-icon" type="image/png" sizes="180x180" href="../apple-touch-icon.png"><link rel="apple-touch-icon" type="image/png" sizes="120x120" href="../apple-touch-icon-120x120.png"><link rel="apple-touch-icon" type="image/png" sizes="76x76" href="../apple-touch-icon-76x76.png"><link rel="apple-touch-icon" type="image/png" sizes="60x60" href="../apple-touch-icon-60x60.png"><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-5.2.2/bootstrap.min.css" rel="stylesheet"><script src="../deps/bootstrap-5.2.2/bootstrap.bundle.min.js"></script><!-- Font Awesome icons --><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.12.1/css/all.min.css" integrity="sha256-mmgLkCYLUQbXn0B1SRqzHar6dCnv9oZFPEC1g1cwlkk=" crossorigin="anonymous"><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.12.1/css/v4-shims.min.css" integrity="sha256-wZjR52fzng1pJHwx4aV2AO3yyTOXrcDW7jBpJtTwVxw=" crossorigin="anonymous"><!-- bootstrap-toc --><script src="https://cdn.jsdelivr.net/gh/afeld/bootstrap-toc@v1.0.1/dist/bootstrap-toc.min.js" integrity="sha256-4veVQbu7//Lk5TSmc7YV48MxtMy98e26cf5MrgZYnwo=" crossorigin="anonymous"></script><!-- headroom.js --><script src="https://cdnjs.cloudflare.com/ajax/libs/headroom/0.11.0/headroom.min.js" integrity="sha256-AsUX4SJE1+yuDu5+mAVzJbuYNPHj/WroHuZ8Ir/CkE0=" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/headroom/0.11.0/jQuery.headroom.min.js" integrity="sha256-ZX/yNShbjqsohH1k95liqY9Gd8uOiE1S4vZc+9KQ1K4=" crossorigin="anonymous"></script><!-- clipboard.js --><script src="https://cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.6/clipboard.min.js" integrity="sha256-inc5kl9MA1hkeYUt+EC3BhlIgyp/2jDIyBLS6k3UxPI=" crossorigin="anonymous"></script><!-- search --><script src="https://cdnjs.cloudflare.com/ajax/libs/fuse.js/6.4.6/fuse.js" integrity="sha512-zv6Ywkjyktsohkbp9bb45V6tEMoWhzFzXis+LrMehmJZZSys19Yxf1dopHx7WzIKxr5tK2dVcYmaCk2uqdjF4A==" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/autocomplete.js/0.38.0/autocomplete.jquery.min.js" integrity="sha512-GU9ayf+66Xx2TmpxqJpliWbT5PiGYxpaG8rfnBEk1LL8l1KGkRShhngwdXK1UgqhAzWpZHSiYPc09/NwDQIGyg==" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/mark.js/8.11.1/mark.min.js" integrity="sha512-5CYOlHXGh6QpOFA/TeTylKLWfB3ftPsde7AnmhuitiTX4K5SqCLBeKro6sPS8ilsz1Q4NRx3v8Ko2IBiszzdww==" crossorigin="anonymous"></script><!-- pkgdown --><script src="../pkgdown.js"></script><script src="../extra.js"></script><meta property="og:title" content="Arrow Arrays — array"><meta property="og:description" content="An Array is an immutable data array with some logical type |
| and some length. Most logical types are contained in the base |
| Array class; there are also subclasses for DictionaryArray, ListArray, |
| and StructArray."><meta property="og:image" content="https://arrow.apache.org/img/arrow-logo_horizontal_black-txt_white-bg.png"><meta property="og:image:alt" content="Apache Arrow logo, displaying the triple chevron image adjacent to the text"><meta name="twitter:card" content="summary_large_image"><meta name="twitter:creator" content="@apachearrow"><meta name="twitter:site" content="@apachearrow"><!-- mathjax --><script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js" integrity="sha256-nvJJv9wWKEm88qvoQl9ekL2J+k/RWIsaSScxxlsrv8k=" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/config/TeX-AMS-MML_HTMLorMML.js" integrity="sha256-84DKXVJXs0/F8OTMzX4UR909+jtl4G7SPypPavF+GfA=" crossorigin="anonymous"></script><!--[if lt IE 9]> |
| <script src="https://oss.maxcdn.com/html5shiv/3.7.3/html5shiv.min.js"></script> |
| <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script> |
| <![endif]--><!-- Matomo --><script> |
| var _paq = window._paq = window._paq || []; |
| /* tracker methods like "setCustomDimension" should be called before "trackPageView" */ |
| /* We explicitly disable cookie tracking to avoid privacy issues */ |
| _paq.push(['disableCookies']); |
| _paq.push(['trackPageView']); |
| _paq.push(['enableLinkTracking']); |
| (function() { |
| var u="https://analytics.apache.org/"; |
| _paq.push(['setTrackerUrl', u+'matomo.php']); |
| _paq.push(['setSiteId', '20']); |
| var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0]; |
| g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s); |
| })(); |
| </script><!-- End Matomo Code --></head><body> |
| <a href="#main" class="visually-hidden-focusable">Skip to contents</a> |
| |
| |
| <nav class="navbar fixed-top navbar-dark navbar-expand-lg bg-black"><div class="container"> |
| |
| <a class="navbar-brand me-2" href="../index.html">Arrow R Package</a> |
| |
| <span class="version"> |
| <small class="nav-text text-muted me-auto" data-bs-toggle="tooltip" data-bs-placement="bottom" title="">11.0.0</small> |
| </span> |
| |
| |
| <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="Toggle navigation"> |
| <span class="navbar-toggler-icon"></span> |
| </button> |
| |
| <div id="navbar" class="collapse navbar-collapse ms-3"> |
| <ul class="navbar-nav me-auto"><li class="nav-item"> |
| <a class="nav-link" href="../articles/arrow.html">Get started</a> |
| </li> |
| <li class="active nav-item"> |
| <a class="nav-link" href="../reference/index.html">Reference</a> |
| </li> |
| <li class="nav-item dropdown"> |
| <a href="#" class="nav-link dropdown-toggle" data-bs-toggle="dropdown" role="button" aria-expanded="false" aria-haspopup="true" id="dropdown-articles">Articles</a> |
| <div class="dropdown-menu" aria-labelledby="dropdown-articles"> |
| <h6 class="dropdown-header" data-toc-skip>Using the package</h6> |
| <a class="dropdown-item" href="../articles/read_write.html">Reading and writing data files</a> |
| <a class="dropdown-item" href="../articles/data_wrangling.html">Data analysis with dplyr syntax</a> |
| <a class="dropdown-item" href="../articles/dataset.html">Working with multi-file data sets</a> |
| <a class="dropdown-item" href="../articles/python.html">Integrating Arrow, Python, and R</a> |
| <a class="dropdown-item" href="../articles/fs.html">Using cloud storage (S3, GCS)</a> |
| <a class="dropdown-item" href="../articles/flight.html">Connecting to a Flight server</a> |
| <div class="dropdown-divider"></div> |
| <h6 class="dropdown-header" data-toc-skip>Arrow concepts</h6> |
| <a class="dropdown-item" href="../articles/data_objects.html">Data objects</a> |
| <a class="dropdown-item" href="../articles/data_types.html">Data types</a> |
| <a class="dropdown-item" href="../articles/metadata.html">Metadata</a> |
| <div class="dropdown-divider"></div> |
| <h6 class="dropdown-header" data-toc-skip>Installation</h6> |
| <a class="dropdown-item" href="../articles/install.html">Installing on Linux</a> |
| <a class="dropdown-item" href="../articles/install_nightly.html">Installing development versions</a> |
| <div class="dropdown-divider"></div> |
| <a class="dropdown-item" href="../articles/index.html">More articles...</a> |
| </div> |
| </li> |
| <li class="nav-item"> |
| <a class="nav-link" href="../news/index.html">Changelog</a> |
| </li> |
| </ul><form class="form-inline my-2 my-lg-0" role="search"> |
| <input type="search" class="form-control me-sm-2" aria-label="Toggle navigation" name="search-input" data-search-index="../search.json" id="search-input" placeholder="Search for" autocomplete="off"></form> |
| |
| <ul class="navbar-nav"></ul></div> |
| |
| |
| </div> |
| </nav><div class="container template-reference-topic"> |
| <div class="row"> |
| <main id="main" class="col-md-9"><div class="page-header"> |
| <img src="" class="logo" alt=""><h1>Arrow Arrays</h1> |
| <small class="dont-index">Source: <a href="https://github.com/apache/arrow/blob/master/r/R/array.R" class="external-link"><code>R/array.R</code></a>, <a href="https://github.com/apache/arrow/blob/master/r/R/scalar.R" class="external-link"><code>R/scalar.R</code></a></small> |
| <div class="d-none name"><code>array.Rd</code></div> |
| </div> |
| |
| <div class="ref-description section level2"> |
| <p>An <code>Array</code> is an immutable data array with some logical type |
| and some length. Most logical types are contained in the base |
| <code>Array</code> class; there are also subclasses for <code>DictionaryArray</code>, <code>ListArray</code>, |
| and <code>StructArray</code>.</p> |
| </div> |
| |
| |
| <div class="section level2"> |
| <h2 id="factory">Factory<a class="anchor" aria-label="anchor" href="#factory"></a></h2> |
| |
| |
| <p>The <code>Array$create()</code> factory method instantiates an <code>Array</code> and |
| takes the following arguments:</p><ul><li><p><code>x</code>: an R vector, list, or <code>data.frame</code></p></li> |
| <li><p><code>type</code>: an optional <a href="data-type.html">data type</a> for <code>x</code>. If omitted, the type |
| will be inferred from the data.</p></li> |
| </ul><p><code>Array$create()</code> will return the appropriate subclass of <code>Array</code>, such as |
| <code>DictionaryArray</code> when given an R factor.</p> |
| <p>To compose a <code>DictionaryArray</code> directly, call <code>DictionaryArray$create()</code>, |
| which takes two arguments:</p><ul><li><p><code>x</code>: an R vector or <code>Array</code> of integers for the dictionary indices</p></li> |
| <li><p><code>dict</code>: an R vector or <code>Array</code> of dictionary values (like R factor levels |
| but not limited to strings only)</p></li> |
| </ul></div> |
| <div class="section level2"> |
| <h2 id="usage">Usage<a class="anchor" aria-label="anchor" href="#usage"></a></h2> |
| |
| |
| |
| <p></p><div class="sourceCode"><pre><code><a class="sourceLine" id="cb1-1" title="1">a <-<span class="st"> </span>Array<span class="op">$</span><span class="kw">create</span>(x)</a> |
| <a class="sourceLine" id="cb1-2" title="2"><span class="kw">length</span>(a)</a> |
| <a class="sourceLine" id="cb1-3" title="3"></a> |
| <a class="sourceLine" id="cb1-4" title="4"><span class="kw">print</span>(a)</a> |
| <a class="sourceLine" id="cb1-5" title="5">a <span class="op">==</span><span class="st"> </span>a</a></code></pre><p></p></div> |
| </div> |
| <div class="section level2"> |
| <h2 id="methods">Methods<a class="anchor" aria-label="anchor" href="#methods"></a></h2> |
| |
| |
| <ul><li><p><code>$IsNull(i)</code>: Return true if value at index is null. Does not boundscheck</p></li> |
| <li><p><code>$IsValid(i)</code>: Return true if value at index is valid. Does not boundscheck</p></li> |
| <li><p><code>$length()</code>: Size in the number of elements this array contains</p></li> |
| <li><p><code>$nbytes()</code>: Total number of bytes consumed by the elements of the array</p></li> |
| <li><p><code>$offset</code>: A relative position into another array's data, to enable zero-copy slicing</p></li> |
| <li><p><code>$null_count</code>: The number of null entries in the array</p></li> |
| <li><p><code>$type</code>: logical type of data</p></li> |
| <li><p><code>$type_id()</code>: type id</p></li> |
| <li><p><code>$Equals(other)</code> : is this array equal to <code>other</code></p></li> |
| <li><p><code>$ApproxEquals(other)</code> :</p></li> |
| <li><p><code>$Diff(other)</code> : return a string expressing the difference between two arrays</p></li> |
| <li><p><code>$data()</code>: return the underlying <a href="ArrayData.html">ArrayData</a></p></li> |
| <li><p><code>$as_vector()</code>: convert to an R vector</p></li> |
| <li><p><code>$ToString()</code>: string representation of the array</p></li> |
| <li><p><code>$Slice(offset, length = NULL)</code>: Construct a zero-copy slice of the array |
| with the indicated offset and length. If length is <code>NULL</code>, the slice goes |
| until the end of the array.</p></li> |
| <li><p><code>$Take(i)</code>: return an <code>Array</code> with values at positions given by integers |
| (R vector or Array Array) <code>i</code>.</p></li> |
| <li><p><code>$Filter(i, keep_na = TRUE)</code>: return an <code>Array</code> with values at positions where logical |
| vector (or Arrow boolean Array) <code>i</code> is <code>TRUE</code>.</p></li> |
| <li><p><code>$SortIndices(descending = FALSE)</code>: return an <code>Array</code> of integer positions that can be |
| used to rearrange the <code>Array</code> in ascending or descending order</p></li> |
| <li><p><code>$RangeEquals(other, start_idx, end_idx, other_start_idx)</code> :</p></li> |
| <li><p><code>$cast(target_type, safe = TRUE, options = cast_options(safe))</code>: Alter the |
| data in the array to change its type.</p></li> |
| <li><p><code>$View(type)</code>: Construct a zero-copy view of this array with the given type.</p></li> |
| <li><p><code>$Validate()</code> : Perform any validation checks to determine obvious inconsistencies |
| within the array's internal data. This can be an expensive check, potentially <code>O(length)</code></p></li> |
| </ul></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">my_array</span> <span class="op"><-</span> <span class="va">Array</span><span class="op">$</span><span class="fu">create</span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">10</span><span class="op">)</span></span></span> |
| <span class="r-in"><span><span class="va">my_array</span><span class="op">$</span><span class="va">type</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> Int32</span> |
| <span class="r-out co"><span class="r-pr">#></span> int32</span> |
| <span class="r-in"><span><span class="va">my_array</span><span class="op">$</span><span class="fu">cast</span><span class="op">(</span><span class="fu"><a href="data-type.html">int8</a></span><span class="op">(</span><span class="op">)</span><span class="op">)</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> Array</span> |
| <span class="r-out co"><span class="r-pr">#></span> <int8></span> |
| <span class="r-out co"><span class="r-pr">#></span> [</span> |
| <span class="r-out co"><span class="r-pr">#></span> 1,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 2,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 3,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 4,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 5,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 6,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 7,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 8,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 9,</span> |
| <span class="r-out co"><span class="r-pr">#></span> 10</span> |
| <span class="r-out co"><span class="r-pr">#></span> ]</span> |
| <span class="r-in"><span></span></span> |
| <span class="r-in"><span><span class="co"># Check if value is null; zero-indexed</span></span></span> |
| <span class="r-in"><span><span class="va">na_array</span> <span class="op"><-</span> <span class="va">Array</span><span class="op">$</span><span class="fu">create</span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">5</span>, <span class="cn">NA</span><span class="op">)</span><span class="op">)</span></span></span> |
| <span class="r-in"><span><span class="va">na_array</span><span class="op">$</span><span class="fu">IsNull</span><span class="op">(</span><span class="fl">0</span><span class="op">)</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] FALSE</span> |
| <span class="r-in"><span><span class="va">na_array</span><span class="op">$</span><span class="fu">IsNull</span><span class="op">(</span><span class="fl">5</span><span class="op">)</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] TRUE</span> |
| <span class="r-in"><span><span class="va">na_array</span><span class="op">$</span><span class="fu">IsValid</span><span class="op">(</span><span class="fl">5</span><span class="op">)</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] FALSE</span> |
| <span class="r-in"><span><span class="va">na_array</span><span class="op">$</span><span class="va">null_count</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] 1</span> |
| <span class="r-in"><span></span></span> |
| <span class="r-in"><span><span class="co"># zero-copy slicing; the offset of the new Array will be the same as the index passed to $Slice</span></span></span> |
| <span class="r-in"><span><span class="va">new_array</span> <span class="op"><-</span> <span class="va">na_array</span><span class="op">$</span><span class="fu">Slice</span><span class="op">(</span><span class="fl">5</span><span class="op">)</span></span></span> |
| <span class="r-in"><span><span class="va">new_array</span><span class="op">$</span><span class="va">offset</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] 5</span> |
| <span class="r-in"><span></span></span> |
| <span class="r-in"><span><span class="co"># Compare 2 arrays</span></span></span> |
| <span class="r-in"><span><span class="va">na_array2</span> <span class="op"><-</span> <span class="va">na_array</span></span></span> |
| <span class="r-in"><span><span class="va">na_array2</span> <span class="op">==</span> <span class="va">na_array</span> <span class="co"># element-wise comparison</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> Array</span> |
| <span class="r-out co"><span class="r-pr">#></span> <bool></span> |
| <span class="r-out co"><span class="r-pr">#></span> [</span> |
| <span class="r-out co"><span class="r-pr">#></span> true,</span> |
| <span class="r-out co"><span class="r-pr">#></span> true,</span> |
| <span class="r-out co"><span class="r-pr">#></span> true,</span> |
| <span class="r-out co"><span class="r-pr">#></span> true,</span> |
| <span class="r-out co"><span class="r-pr">#></span> true,</span> |
| <span class="r-out co"><span class="r-pr">#></span> null</span> |
| <span class="r-out co"><span class="r-pr">#></span> ]</span> |
| <span class="r-in"><span><span class="va">na_array2</span><span class="op">$</span><span class="fu">Equals</span><span class="op">(</span><span class="va">na_array</span><span class="op">)</span> <span class="co"># overall comparison</span></span></span> |
| <span class="r-out co"><span class="r-pr">#></span> [1] TRUE</span> |
| </code></pre></div> |
| </div> |
| </main><aside class="col-md-3"><nav id="toc"><h2>On this page</h2> |
| </nav></aside></div> |
| |
| |
| <footer><div class="pkgdown-footer-left"> |
| <p></p><p><a href="https://arrow.apache.org/docs/r/versions.html">Older versions of these docs</a></p> |
| </div> |
| |
| <div class="pkgdown-footer-right"> |
| <p></p><p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.7.</p> |
| </div> |
| |
| </footer></div> |
| |
| |
| |
| |
| |
| </body></html> |
| |
