struct.Isaac64Rng.html 22 KB

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  1. <!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="API documentation for the Rust `Isaac64Rng` struct in crate `rand`."><meta name="keywords" content="rust, rustlang, rust-lang, Isaac64Rng"><title>rand::prng::isaac64::Isaac64Rng - Rust</title><link rel="stylesheet" type="text/css" href="../../../normalize.css"><link rel="stylesheet" type="text/css" href="../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../../dark.css"><link rel="stylesheet" type="text/css" href="../../../light.css" id="themeStyle"><script src="../../../storage.js"></script><link rel="shortcut icon" href="https://www.rust-lang.org/favicon.ico"></head><body class="rustdoc struct"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">&#9776;</div><a href='../../../rand/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk.png' alt='logo' width='100'></a><p class='location'>Struct Isaac64Rng</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.new_unseeded">new_unseeded</a><a href="#method.new_from_u64">new_from_u64</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Clone">Clone</a><a href="#impl-Debug">Debug</a><a href="#impl-RngCore">RngCore</a><a href="#impl-SeedableRng">SeedableRng</a></div><a class="sidebar-title" href="#synthetic-implementations">Auto Trait Implementations</a><div class="sidebar-links"><a href="#impl-Send">Send</a><a href="#impl-Sync">Sync</a></div></div><p class='location'><a href='../../index.html'>rand</a>::<wbr><a href='../index.html'>prng</a>::<wbr><a href='index.html'>isaac64</a></p><script>window.sidebarCurrent = {name: 'Isaac64Rng', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../../theme.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><input class="search-input" name="search" autocomplete="off" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><a id="settings-menu" href="../../../settings.html"><img src="../../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='in-band'>Struct <a href='../../index.html'>rand</a>::<wbr><a href='../index.html'>prng</a>::<wbr><a href='index.html'>isaac64</a>::<wbr><a class="struct" href=''>Isaac64Rng</a></span><span class='out-of-band'><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>&#x2212;</span>]</a></span><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#85' title='goto source code'>[src]</a></span></h1><div class="docblock type-decl"><pre class='rust struct'>pub struct Isaac64Rng(_);</pre></div><div class='docblock'><p>A random number generator that uses ISAAC-64, the 64-bit variant of the
  2. ISAAC algorithm.</p>
  3. <p>ISAAC stands for &quot;Indirection, Shift, Accumulate, Add, and Count&quot; which are
  4. the principal bitwise operations employed. It is the most advanced of a
  5. series of array based random number generator designed by Robert Jenkins
  6. in 1996<sup id="fnref1"><a href="#fn1">1</a></sup>.</p>
  7. <p>ISAAC-64 is mostly similar to ISAAC. Because it operates on 64-bit integers
  8. instead of 32-bit, it uses twice as much memory to hold its state and
  9. results. Also it uses different constants for shifts and indirect indexing,
  10. optimized to give good results for 64bit arithmetic.</p>
  11. <p>ISAAC-64 is notably fast and produces excellent quality random numbers for
  12. non-cryptographic applications.</p>
  13. <p>In spite of being designed with cryptographic security in mind, ISAAC hasn't
  14. been stringently cryptanalyzed and thus cryptographers do not not
  15. consensually trust it to be secure. When looking for a secure RNG, prefer
  16. <a href="../hc128/struct.Hc128Rng.html"><code>Hc128Rng</code></a> instead, which, like ISAAC, is an array-based RNG and one of
  17. the stream-ciphers selected the by eSTREAM contest.</p>
  18. <h2 id="overview-of-the-isaac-64-algorithm" class="section-header"><a href="#overview-of-the-isaac-64-algorithm">Overview of the ISAAC-64 algorithm:</a></h2>
  19. <p>(in pseudo-code)</p>
  20. <pre><code class="language-text">Input: a, b, c, s[256] // state
  21. Output: r[256] // results
  22. mix(a,i) = !(a ^ a &lt;&lt; 21) if i = 0 mod 4
  23. a ^ a &gt;&gt; 5 if i = 1 mod 4
  24. a ^ a &lt;&lt; 12 if i = 2 mod 4
  25. a ^ a &gt;&gt; 33 if i = 3 mod 4
  26. c = c + 1
  27. b = b + c
  28. for i in 0..256 {
  29. x = s_[i]
  30. a = mix(a,i) + s[i+128 mod 256]
  31. y = a + b + s[x&gt;&gt;3 mod 256]
  32. s[i] = y
  33. b = x + s[y&gt;&gt;11 mod 256]
  34. r[i] = b
  35. }
  36. </code></pre>
  37. <p>This implementation uses <a href="../../../rand_core/block/struct.BlockRng64.html"><code>BlockRng64</code></a> to implement the <a href="../../trait.RngCore.html"><code>RngCore</code></a> methods.</p>
  38. <p>See for more information the documentation of <a href="../isaac/struct.IsaacRng.html"><code>IsaacRng</code></a>.</p>
  39. <div class="footnotes"><hr><ol><li id="fn1">
  40. <p>Bob Jenkins, <a href="http://burtleburtle.net/bob/rand/isaac.html"><em>ISAAC and RC4</em></a>&nbsp;<a href="#fnref1" rev="footnote">↩</a></p></li></ol></div></div>
  41. <h2 id='methods' class='small-section-header'>
  42. Methods<a href='#methods' class='anchor'></a>
  43. </h2>
  44. <h3 id='impl' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#119-135' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.new_unseeded' class="method"><span id='new_unseeded.v' class='invisible'><table class='table-display'><tbody><tr><td><code>pub fn <a href='#method.new_unseeded' class='fnname'>new_unseeded</a>() -&gt; Self</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#125-127' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='stability'><div class='stab deprecated'>Deprecated since 0.5.0<p>: use the FromEntropy or SeedableRng trait</p>
  45. </div></div><div class='docblock'><p>Create a 64-bit ISAAC random number generator using the
  46. default fixed seed.</p>
  47. <p>DEPRECATED. <code>Isaac64Rng::new_from_u64(0)</code> will produce identical results.</p>
  48. </div><h4 id='method.new_from_u64' class="method"><span id='new_from_u64.v' class='invisible'><table class='table-display'><tbody><tr><td><code>pub fn <a href='#method.new_from_u64' class='fnname'>new_from_u64</a>(seed: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>) -&gt; Self</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#132-134' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Create an ISAAC-64 random number generator using an <code>u64</code> as seed.
  49. If <code>seed == 0</code> this will produce the same stream of random numbers as
  50. the reference implementation when used unseeded.</p>
  51. </div></div>
  52. <h2 id='implementations' class='small-section-header'>
  53. Trait Implementations<a href='#implementations' class='anchor'></a>
  54. </h2>
  55. <div id='implementations-list'><h3 id='impl-Clone' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-Clone' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#83' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.clone' class="method"><span id='clone.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone' class='fnname'>clone</a>(&amp;self) -&gt; <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#83' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Returns a copy of the value. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone">Read more</a></p>
  56. </div><h4 id='method.clone_from' class="method"><span id='clone_from.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from' class='fnname'>clone_from</a>(&amp;mut self, source: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;</a>Self)</code></span></td><td><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.0.0'>1.0.0</div><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/clone.rs.html#130-132' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from">Read more</a></p>
  57. </div></div><h3 id='impl-Debug' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-Debug' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#83' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&amp;self, f: &amp;mut <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#83' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
  58. </div></div><h3 id='impl-RngCore' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="../../../rand/trait.RngCore.html" title="trait rand::RngCore">RngCore</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-RngCore' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#87-105' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.next_u32' class="method"><span id='next_u32.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.RngCore.html#tymethod.next_u32' class='fnname'>next_u32</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u32.html">u32</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#89-91' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Return the next random <code>u32</code>. <a href="../../../rand/trait.RngCore.html#tymethod.next_u32">Read more</a></p>
  59. </div><h4 id='method.next_u64' class="method"><span id='next_u64.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.RngCore.html#tymethod.next_u64' class='fnname'>next_u64</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#94-96' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Return the next random <code>u64</code>. <a href="../../../rand/trait.RngCore.html#tymethod.next_u64">Read more</a></p>
  60. </div><h4 id='method.fill_bytes' class="method"><span id='fill_bytes.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.RngCore.html#tymethod.fill_bytes' class='fnname'>fill_bytes</a>(&amp;mut self, dest: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&amp;mut [</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u8.html">u8</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">]</a>)</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#98-100' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Fill <code>dest</code> with random data. <a href="../../../rand/trait.RngCore.html#tymethod.fill_bytes">Read more</a></p>
  61. </div><h4 id='method.try_fill_bytes' class="method"><span id='try_fill_bytes.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.RngCore.html#tymethod.try_fill_bytes' class='fnname'>try_fill_bytes</a>(&amp;mut self, dest: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&amp;mut [</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u8.html">u8</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">]</a>) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>, <a class="struct" href="../../../rand/struct.Error.html" title="struct rand::Error">Error</a>&gt;</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#102-104' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Fill <code>dest</code> entirely with random data. <a href="../../../rand/trait.RngCore.html#tymethod.try_fill_bytes">Read more</a></p>
  62. </div></div><h3 id='impl-SeedableRng' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="../../../rand/trait.SeedableRng.html" title="trait rand::SeedableRng">SeedableRng</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-SeedableRng' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#107-117' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='associatedtype.Seed' class="type"><span id='Seed.t' class='invisible'><code>type <a href='../../../rand/trait.SeedableRng.html#associatedtype.Seed' class="type">Seed</a> = &lt;<a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Core.html" title="struct rand::prng::isaac64::Isaac64Core">Isaac64Core</a> as <a class="trait" href="../../../rand/trait.SeedableRng.html" title="trait rand::SeedableRng">SeedableRng</a>&gt;::<a class="type" href="../../../rand/trait.SeedableRng.html#associatedtype.Seed" title="type rand::SeedableRng::Seed">Seed</a></code></span></h4>
  63. <div class='docblock'><p>Seed type, which is restricted to types mutably-dereferencable as <code>u8</code> arrays (we recommend <code>[u8; N]</code> for some <code>N</code>). <a href="../../../rand/trait.SeedableRng.html#associatedtype.Seed">Read more</a></p>
  64. </div><h4 id='method.from_seed' class="method"><span id='from_seed.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.SeedableRng.html#tymethod.from_seed' class='fnname'>from_seed</a>(seed: Self::<a class="type" href="../../../rand/trait.SeedableRng.html#associatedtype.Seed" title="type rand::SeedableRng::Seed">Seed</a>) -&gt; Self</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#110-112' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Create a new PRNG using the given seed. <a href="../../../rand/trait.SeedableRng.html#tymethod.from_seed">Read more</a></p>
  65. </div><h4 id='method.from_rng' class="method"><span id='from_rng.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../../rand/trait.SeedableRng.html#method.from_rng' class='fnname'>from_rng</a>&lt;S:&nbsp;<a class="trait" href="../../../rand/trait.RngCore.html" title="trait rand::RngCore">RngCore</a>&gt;(rng: S) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;Self, <a class="struct" href="../../../rand/struct.Error.html" title="struct rand::Error">Error</a>&gt;</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/rand/prng/isaac64.rs.html#114-116' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Create a new PRNG seeded from another <code>Rng</code>. <a href="../../../rand/trait.SeedableRng.html#method.from_rng">Read more</a></p>
  66. </div></div></div>
  67. <h2 id='synthetic-implementations' class='small-section-header'>
  68. Auto Trait Implementations<a href='#synthetic-implementations' class='anchor'></a>
  69. </h2>
  70. <div id='synthetic-implementations-list'>
  71. <h3 id='impl-Send' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-Send' class='anchor'></a></span></td><td><span class='out-of-band'></span></td></tr></tbody></table></h3><div class='impl-items'></div><h3 id='impl-Sync' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="../../../rand/prng/isaac64/struct.Isaac64Rng.html" title="struct rand::prng::isaac64::Isaac64Rng">Isaac64Rng</a></code><a href='#impl-Sync' class='anchor'></a></span></td><td><span class='out-of-band'></span></td></tr></tbody></table></h3><div class='impl-items'></div></div></section><section id="search" class="content hidden"></section><section class="footer"></section><aside id="help" class="hidden"><div><h1 class="hidden">Help</h1><div class="shortcuts"><h2>Keyboard Shortcuts</h2><dl><dt><kbd>?</kbd></dt><dd>Show this help dialog</dd><dt><kbd>S</kbd></dt><dd>Focus the search field</dd><dt><kbd>↑</kbd></dt><dd>Move up in search results</dd><dt><kbd>↓</kbd></dt><dd>Move down in search results</dd><dt><kbd>↹</kbd></dt><dd>Switch tab</dd><dt><kbd>&#9166;</kbd></dt><dd>Go to active search result</dd><dt><kbd>+</kbd></dt><dd>Expand all sections</dd><dt><kbd>-</kbd></dt><dd>Collapse all sections</dd></dl></div><div class="infos"><h2>Search Tricks</h2><p>Prefix searches with a type followed by a colon (e.g. <code>fn:</code>) to restrict the search to a given type.</p><p>Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>.</p><p>Search functions by type signature (e.g. <code>vec -> usize</code> or <code>* -> vec</code>)</p><p>Search multiple things at once by splitting your query with comma (e.g. <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../../../";window.currentCrate = "rand";</script><script src="../../../aliases.js"></script><script src="../../../main.js"></script><script defer src="../../../search-index.js"></script></body></html>