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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="Take elements by index from Array, creating a new Array from those indexes."><title>take 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="#">take</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="#">take</a></h2><h3><a href="#">Sections</a></h3><ul class="block top-toc"><li><a href="#errors" title="Errors">Errors</a></li><li><a href="#safety" title="Safety">Safety</a></li><li><a href="#see-also" title="See also">See also</a></li><li><a href="#examples" title="Examples">Examples</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">take</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 take(
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values: &dyn Array,
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indices: &dyn Array,
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options: <a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="struct" href="struct.TakeOptions.html" title="struct datatypes::compute::TakeOptions">TakeOptions</a>>,
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) -> <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="https://doc.rust-lang.org/nightly/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc">Arc</a><dyn Array>, ArrowError></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Take elements by index from [Array], creating a new [Array] from those indexes.</p>
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<div class="example-wrap"><pre class="language-text"><code>┌─────────────────┐ ┌─────────┐ ┌─────────────────┐
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│ A │ │ 0 │ │ A │
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├─────────────────┤ ├─────────┤ ├─────────────────┤
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│ D │ │ 2 │ │ B │
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├─────────────────┤ ├─────────┤ take(values, indices) ├─────────────────┤
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│ B │ │ 3 │ ─────────────────────────▶ │ C │
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├─────────────────┤ ├─────────┤ ├─────────────────┤
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│ C │ │ 1 │ │ D │
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├─────────────────┤ └─────────┘ └─────────────────┘
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│ E │
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└─────────────────┘
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values array indices array result</code></pre></div>
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<p>For selecting values by index from multiple arrays see <a href="kernels/interleave/index.html" title="mod datatypes::compute::kernels::interleave"><code>crate::interleave</code></a></p>
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<p>Note that this kernel, similar to other kernels in this crate,
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will avoid allocating where not necessary. Consequently
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the returned array may share buffers with the inputs</p>
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<h2 id="errors"><a class="doc-anchor" href="#errors">§</a>Errors</h2>
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<p>This function errors whenever:</p>
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<ul>
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<li>An index cannot be casted to <code>usize</code> (typically 32 bit architectures)</li>
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<li>An index is out of bounds and <code>options</code> is set to check bounds.</li>
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</ul>
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<h2 id="safety"><a class="doc-anchor" href="#safety">§</a>Safety</h2>
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<p>When <code>options</code> is not set to check bounds, taking indexes after <code>len</code> will panic.</p>
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<h2 id="see-also"><a class="doc-anchor" href="#see-also">§</a>See also</h2>
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<ul>
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<li><a href="struct.BatchCoalescer.html" title="struct datatypes::compute::BatchCoalescer"><code>BatchCoalescer</code></a>: to filter multiple [<code>RecordBatch</code>] and coalesce
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the results into a single array.</li>
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</ul>
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<h2 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples</h2>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>values = StringArray::from(<span class="macro">vec!</span>[<span class="string">"zero"</span>, <span class="string">"one"</span>, <span class="string">"two"</span>]);
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<span class="comment">// Take items at index 2, and 1:
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</span><span class="kw">let </span>indices = UInt32Array::from(<span class="macro">vec!</span>[<span class="number">2</span>, <span class="number">1</span>]);
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<span class="kw">let </span>taken = take(<span class="kw-2">&</span>values, <span class="kw-2">&</span>indices, <span class="prelude-val">None</span>).unwrap();
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<span class="kw">let </span>taken = taken.as_string::<i32>();
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<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>taken, StringArray::from(<span class="macro">vec!</span>[<span class="string">"two"</span>, <span class="string">"one"</span>]));</code></pre></div></div></details></section></div></main></body></html> |