| <!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="Collections implemented with bit vectors."><meta name="keywords" content="rust, rustlang, rust-lang, bit_vec"><title>bit_vec - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../normalize.css"><link rel="stylesheet" href="../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../ayu.css" disabled><link rel="stylesheet" href="../dark.css" disabled><link rel="stylesheet" href="../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../storage.js"></script><script defer src="../crates.js"></script><script defer src="../main.js"></script><noscript><link rel="stylesheet" href="../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../favicon.svg"></head><body class="rustdoc mod crate"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../bit_vec/index.html"><div class="logo-container"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../bit_vec/index.html"><div class="logo-container"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">Crate bit_vec</a></h2><div class="sidebar-elems"><ul class="block"><li class="version">Version 0.6.3</li><li><a id="all-types" href="all.html">All Items</a></li></ul><section><ul class="block"><li><a href="#structs">Structs</a></li><li><a href="#traits">Traits</a></li></ul></section></div></nav><main><div class="width-limiter"><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn">Crate <a class="mod" href="#">bit_vec</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../src/bit_vec/lib.rs.html#28-2535">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Collections implemented with bit vectors.</p> |
| <h2 id="examples"><a href="#examples">Examples</a></h2> |
| <p>This is a simple example of the <a href="http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes">Sieve of Eratosthenes</a> |
| which calculates prime numbers up to a given limit.</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>bit_vec::BitVec; |
| |
| <span class="kw">let </span>max_prime = <span class="number">10000</span>; |
| |
| <span class="comment">// Store the primes as a BitVec |
| </span><span class="kw">let </span>primes = { |
| <span class="comment">// Assume all numbers are prime to begin, and then we |
| // cross off non-primes progressively |
| </span><span class="kw">let </span><span class="kw-2">mut </span>bv = BitVec::from_elem(max_prime, <span class="bool-val">true</span>); |
| |
| <span class="comment">// Neither 0 nor 1 are prime |
| </span>bv.set(<span class="number">0</span>, <span class="bool-val">false</span>); |
| bv.set(<span class="number">1</span>, <span class="bool-val">false</span>); |
| |
| <span class="kw">for </span>i <span class="kw">in </span><span class="number">2</span>.. <span class="number">1 </span>+ (max_prime <span class="kw">as </span>f64).sqrt() <span class="kw">as </span>usize { |
| <span class="comment">// if i is a prime |
| </span><span class="kw">if </span>bv[i] { |
| <span class="comment">// Mark all multiples of i as non-prime (any multiples below i * i |
| // will have been marked as non-prime previously) |
| </span><span class="kw">for </span>j <span class="kw">in </span>i.. { |
| <span class="kw">if </span>i * j >= max_prime { |
| <span class="kw">break</span>; |
| } |
| bv.set(i * j, <span class="bool-val">false</span>) |
| } |
| } |
| } |
| bv |
| }; |
| |
| <span class="comment">// Simple primality tests below our max bound |
| </span><span class="kw">let </span>print_primes = <span class="number">20</span>; |
| <span class="macro">print!</span>(<span class="string">"The primes below {} are: "</span>, print_primes); |
| <span class="kw">for </span>x <span class="kw">in </span><span class="number">0</span>..print_primes { |
| <span class="kw">if </span>primes.get(x).unwrap_or(<span class="bool-val">false</span>) { |
| <span class="macro">print!</span>(<span class="string">"{} "</span>, x); |
| } |
| } |
| <span class="macro">println!</span>(); |
| |
| <span class="kw">let </span>num_primes = primes.iter().filter(|x| <span class="kw-2">*</span>x).count(); |
| <span class="macro">println!</span>(<span class="string">"There are {} primes below {}"</span>, num_primes, max_prime); |
| <span class="macro">assert_eq!</span>(num_primes, <span class="number">1_229</span>);</code></pre></div> |
| </div></details><h2 id="structs" class="small-section-header"><a href="#structs">Structs</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.BitVec.html" title="bit_vec::BitVec struct">BitVec</a></div><div class="item-right docblock-short">The bitvector type.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.Blocks.html" title="bit_vec::Blocks struct">Blocks</a></div><div class="item-right docblock-short">An iterator over the blocks of a <code>BitVec</code>.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.IntoIter.html" title="bit_vec::IntoIter struct">IntoIter</a></div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.Iter.html" title="bit_vec::Iter struct">Iter</a></div><div class="item-right docblock-short">An iterator for <code>BitVec</code>.</div></div></div><h2 id="traits" class="small-section-header"><a href="#traits">Traits</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="trait" href="trait.BitBlock.html" title="bit_vec::BitBlock trait">BitBlock</a></div><div class="item-right docblock-short">Abstracts over a pile of bits (basically unsigned primitives)</div></div></div></section></div></main><div id="rustdoc-vars" data-root-path="../" data-current-crate="bit_vec" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
