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<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Given a list of lexicographically sorted columns, computes the `Partitions`, where a partition consists of the set of consecutive rows with equal values"><title>partition in datatypes::compute - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../static.files/rustdoc-17e0aaed.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="datatypes" data-themes="" data-resource-suffix="" data-rustdoc-version="1.96.0-nightly (ac7f9ec7d 2026-03-20)" data-channel="nightly" data-search-js="search-63369b7b.js" data-stringdex-js="stringdex-2da4960a.js" data-settings-js="settings-170eb4bf.js" ><script src="../../static.files/storage-41dd4d93.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-5013f961.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-f7c3ffd8.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-044be391.svg"></head><body class="rustdoc fn"><a class="skip-main-content" href="#main-content">Skip to main content</a><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><rustdoc-topbar><h2><a href="#">partition</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../datatypes/index.html">datatypes</a><span class="version">1.0.0</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">partition</a></h2><h3><a href="#">Sections</a></h3><ul class="block top-toc"><li><a href="#example" title="Example:">Example:</a></li><li><a href="#example-code" title="Example Code">Example Code</a></li></ul></section><div id="rustdoc-modnav"><h2><a href="index.html">In datatypes::<wbr>compute</a></h2></div></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><div class="width-limiter"><section id="main-content" class="content" tabindex="-1"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../index.html">datatypes</a>::<wbr><a href="index.html">compute</a></div><h1>Function <span class="fn">partition</span> <button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"></span></div><pre class="rust item-decl"><code>pub fn partition(columns: &[<a class="struct" href="https://doc.rust-lang.org/nightly/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc">Arc</a><dyn Array>]) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="struct" href="struct.Partitions.html" title="struct datatypes::compute::Partitions">Partitions</a>, ArrowError></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Given a list of lexicographically sorted columns, computes the <a href="struct.Partitions.html" title="struct datatypes::compute::Partitions"><code>Partitions</code></a>,
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where a partition consists of the set of consecutive rows with equal values</p>
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<p>Returns an error if no columns are specified or all columns do not
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have the same number of rows.</p>
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<h2 id="example"><a class="doc-anchor" href="#example">§</a>Example:</h2>
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<p>For example, given columns <code>x</code>, <code>y</code> and <code>z</code>, calling
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<a href="fn.partition.html" title="fn datatypes::compute::partition"><code>partition</code></a><code>(values, (x, y))</code> will divide the
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rows into ranges where the values of <code>(x, y)</code> are equal:</p>
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<div class="example-wrap"><pre class="language-text"><code>┌ ─ ┬───┬ ─ ─┌───┐─ ─ ┬───┬ ─ ─ ┐
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│ 1 │ │ 1 │ │ A │ Range: 0..1 (x=1, y=1)
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├ ─ ┼───┼ ─ ─├───┤─ ─ ┼───┼ ─ ─ ┤
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│ 1 │ │ 2 │ │ B │
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│ ├───┤ ├───┤ ├───┤ │
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│ 1 │ │ 2 │ │ C │ Range: 1..4 (x=1, y=2)
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│ ├───┤ ├───┤ ├───┤ │
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│ 1 │ │ 2 │ │ D │
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├ ─ ┼───┼ ─ ─├───┤─ ─ ┼───┼ ─ ─ ┤
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│ 2 │ │ 1 │ │ E │ Range: 4..5 (x=2, y=1)
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├ ─ ┼───┼ ─ ─├───┤─ ─ ┼───┼ ─ ─ ┤
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│ 3 │ │ 1 │ │ F │ Range: 5..6 (x=3, y=1)
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└ ─ ┴───┴ ─ ─└───┘─ ─ ┴───┴ ─ ─ ┘
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x y z partition(&[x, y])</code></pre></div><h2 id="example-code"><a class="doc-anchor" href="#example-code">§</a>Example Code</h2>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>batch = RecordBatch::try_from_iter(<span class="macro">vec!</span>[
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(<span class="string">"x"</span>, Arc::new(Int64Array::from(<span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>])) <span class="kw">as </span>ArrayRef),
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(<span class="string">"y"</span>, Arc::new(Int64Array::from(<span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">2</span>, <span class="number">2</span>, <span class="number">2</span>, <span class="number">1</span>, <span class="number">1</span>])) <span class="kw">as </span>ArrayRef),
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(<span class="string">"z"</span>, Arc::new(StringArray::from(<span class="macro">vec!</span>[<span class="string">"A"</span>, <span class="string">"B"</span>, <span class="string">"C"</span>, <span class="string">"D"</span>, <span class="string">"E"</span>, <span class="string">"F"</span>])) <span class="kw">as </span>ArrayRef),
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]).unwrap();
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<span class="comment">// Partition on first two columns
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</span><span class="kw">let </span>ranges = partition(<span class="kw-2">&</span>batch.columns()[..<span class="number">2</span>]).unwrap().ranges();
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<span class="kw">let </span>expected = <span class="macro">vec!</span>[
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(<span class="number">0</span>..<span class="number">1</span>),
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(<span class="number">1</span>..<span class="number">4</span>),
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(<span class="number">4</span>..<span class="number">5</span>),
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(<span class="number">5</span>..<span class="number">6</span>),
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];
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<span class="macro">assert_eq!</span>(ranges, expected);</code></pre></div></div></details></section></div></main></body></html> |