trait.Real.html 76 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795
  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="utf-8">
  5. <meta name="viewport" content="width=device-width, initial-scale=1.0">
  6. <meta name="generator" content="rustdoc">
  7. <meta name="description" content="API documentation for the Rust `Real` trait in crate `num_traits`.">
  8. <meta name="keywords" content="rust, rustlang, rust-lang, Real">
  9. <title>num_traits::real::Real - Rust</title>
  10. <link rel="stylesheet" type="text/css" href="../../normalize.css">
  11. <link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle">
  12. <link rel="stylesheet" type="text/css" href="../../dark.css">
  13. <link rel="stylesheet" type="text/css" href="../../main.css" id="themeStyle">
  14. <script src="../../storage.js"></script>
  15. </head>
  16. <body class="rustdoc trait">
  17. <!--[if lte IE 8]>
  18. <div class="warning">
  19. This old browser is unsupported and will most likely display funky
  20. things.
  21. </div>
  22. <![endif]-->
  23. <nav class="sidebar">
  24. <div class="sidebar-menu">&#9776;</div>
  25. <p class='location'>Trait Real</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#required-methods">Required Methods</a><div class="sidebar-links"><a href="#tymethod.min_value">min_value</a><a href="#tymethod.min_positive_value">min_positive_value</a><a href="#tymethod.epsilon">epsilon</a><a href="#tymethod.max_value">max_value</a><a href="#tymethod.floor">floor</a><a href="#tymethod.ceil">ceil</a><a href="#tymethod.round">round</a><a href="#tymethod.trunc">trunc</a><a href="#tymethod.fract">fract</a><a href="#tymethod.abs">abs</a><a href="#tymethod.signum">signum</a><a href="#tymethod.is_sign_positive">is_sign_positive</a><a href="#tymethod.is_sign_negative">is_sign_negative</a><a href="#tymethod.mul_add">mul_add</a><a href="#tymethod.recip">recip</a><a href="#tymethod.powi">powi</a><a href="#tymethod.powf">powf</a><a href="#tymethod.sqrt">sqrt</a><a href="#tymethod.exp">exp</a><a href="#tymethod.exp2">exp2</a><a href="#tymethod.ln">ln</a><a href="#tymethod.log">log</a><a href="#tymethod.log2">log2</a><a href="#tymethod.log10">log10</a><a href="#tymethod.to_degrees">to_degrees</a><a href="#tymethod.to_radians">to_radians</a><a href="#tymethod.max">max</a><a href="#tymethod.min">min</a><a href="#tymethod.abs_sub">abs_sub</a><a href="#tymethod.cbrt">cbrt</a><a href="#tymethod.hypot">hypot</a><a href="#tymethod.sin">sin</a><a href="#tymethod.cos">cos</a><a href="#tymethod.tan">tan</a><a href="#tymethod.asin">asin</a><a href="#tymethod.acos">acos</a><a href="#tymethod.atan">atan</a><a href="#tymethod.atan2">atan2</a><a href="#tymethod.sin_cos">sin_cos</a><a href="#tymethod.exp_m1">exp_m1</a><a href="#tymethod.ln_1p">ln_1p</a><a href="#tymethod.sinh">sinh</a><a href="#tymethod.cosh">cosh</a><a href="#tymethod.tanh">tanh</a><a href="#tymethod.asinh">asinh</a><a href="#tymethod.acosh">acosh</a><a href="#tymethod.atanh">atanh</a></div><a class="sidebar-title" href="#implementors">Implementors</a></div><p class='location'><a href='../index.html'>num_traits</a>::<wbr><a href='index.html'>real</a></p><script>window.sidebarCurrent = {name: 'Real', ty: 'trait', relpath: ''};</script><script defer src="sidebar-items.js"></script></div>
  26. </nav>
  27. <div class="theme-picker">
  28. <button id="theme-picker" aria-label="Pick another theme!">
  29. <img src="../../brush.svg" width="18" alt="Pick another theme!">
  30. </button>
  31. <div id="theme-choices"></div>
  32. </div>
  33. <script src="../../theme.js"></script>
  34. <nav class="sub">
  35. <form class="search-form js-only">
  36. <div class="search-container">
  37. <input class="search-input" name="search"
  38. autocomplete="off"
  39. placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
  40. type="search">
  41. </div>
  42. </form>
  43. </nav>
  44. <section id='main' class="content">
  45. <h1 class='fqn'><span class='in-band'>Trait <a href='../index.html'>num_traits</a>::<wbr><a href='index.html'>real</a>::<wbr><a class="trait" href=''>Real</a></span><span class='out-of-band'><span id='render-detail'>
  46. <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
  47. [<span class='inner'>&#x2212;</span>]
  48. </a>
  49. </span><a class='srclink' href='../../src/num_traits/real.rs.html#15-782' title='goto source code'>[src]</a></span></h1>
  50. <pre class='rust trait'>pub trait Real: <a class="trait" href="../../num_traits/cast/trait.NumCast.html" title="trait num_traits::cast::NumCast">NumCast</a> + <a class="trait" href="../../num_traits/trait.Num.html" title="trait num_traits::Num">Num</a> + <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Copy.html" title="trait core::marker::Copy">Copy</a> + <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/arith/trait.Neg.html" title="trait core::ops::arith::Neg">Neg</a>&lt;Output = Self&gt; + <a class="trait" href="https://doc.rust-lang.org/nightly/core/cmp/trait.PartialOrd.html" title="trait core::cmp::PartialOrd">PartialOrd</a>&lt;Self&gt; {
  51. fn <a href='#tymethod.min_value' class='fnname'>min_value</a>() -&gt; Self;
  52. <div class='item-spacer'></div> fn <a href='#tymethod.min_positive_value' class='fnname'>min_positive_value</a>() -&gt; Self;
  53. <div class='item-spacer'></div> fn <a href='#tymethod.epsilon' class='fnname'>epsilon</a>() -&gt; Self;
  54. <div class='item-spacer'></div> fn <a href='#tymethod.max_value' class='fnname'>max_value</a>() -&gt; Self;
  55. <div class='item-spacer'></div> fn <a href='#tymethod.floor' class='fnname'>floor</a>(self) -&gt; Self;
  56. <div class='item-spacer'></div> fn <a href='#tymethod.ceil' class='fnname'>ceil</a>(self) -&gt; Self;
  57. <div class='item-spacer'></div> fn <a href='#tymethod.round' class='fnname'>round</a>(self) -&gt; Self;
  58. <div class='item-spacer'></div> fn <a href='#tymethod.trunc' class='fnname'>trunc</a>(self) -&gt; Self;
  59. <div class='item-spacer'></div> fn <a href='#tymethod.fract' class='fnname'>fract</a>(self) -&gt; Self;
  60. <div class='item-spacer'></div> fn <a href='#tymethod.abs' class='fnname'>abs</a>(self) -&gt; Self;
  61. <div class='item-spacer'></div> fn <a href='#tymethod.signum' class='fnname'>signum</a>(self) -&gt; Self;
  62. <div class='item-spacer'></div> fn <a href='#tymethod.is_sign_positive' class='fnname'>is_sign_positive</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a>;
  63. <div class='item-spacer'></div> fn <a href='#tymethod.is_sign_negative' class='fnname'>is_sign_negative</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a>;
  64. <div class='item-spacer'></div> fn <a href='#tymethod.mul_add' class='fnname'>mul_add</a>(self, a: Self, b: Self) -&gt; Self;
  65. <div class='item-spacer'></div> fn <a href='#tymethod.recip' class='fnname'>recip</a>(self) -&gt; Self;
  66. <div class='item-spacer'></div> fn <a href='#tymethod.powi' class='fnname'>powi</a>(self, n: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.i32.html">i32</a>) -&gt; Self;
  67. <div class='item-spacer'></div> fn <a href='#tymethod.powf' class='fnname'>powf</a>(self, n: Self) -&gt; Self;
  68. <div class='item-spacer'></div> fn <a href='#tymethod.sqrt' class='fnname'>sqrt</a>(self) -&gt; Self;
  69. <div class='item-spacer'></div> fn <a href='#tymethod.exp' class='fnname'>exp</a>(self) -&gt; Self;
  70. <div class='item-spacer'></div> fn <a href='#tymethod.exp2' class='fnname'>exp2</a>(self) -&gt; Self;
  71. <div class='item-spacer'></div> fn <a href='#tymethod.ln' class='fnname'>ln</a>(self) -&gt; Self;
  72. <div class='item-spacer'></div> fn <a href='#tymethod.log' class='fnname'>log</a>(self, base: Self) -&gt; Self;
  73. <div class='item-spacer'></div> fn <a href='#tymethod.log2' class='fnname'>log2</a>(self) -&gt; Self;
  74. <div class='item-spacer'></div> fn <a href='#tymethod.log10' class='fnname'>log10</a>(self) -&gt; Self;
  75. <div class='item-spacer'></div> fn <a href='#tymethod.to_degrees' class='fnname'>to_degrees</a>(self) -&gt; Self;
  76. <div class='item-spacer'></div> fn <a href='#tymethod.to_radians' class='fnname'>to_radians</a>(self) -&gt; Self;
  77. <div class='item-spacer'></div> fn <a href='#tymethod.max' class='fnname'>max</a>(self, other: Self) -&gt; Self;
  78. <div class='item-spacer'></div> fn <a href='#tymethod.min' class='fnname'>min</a>(self, other: Self) -&gt; Self;
  79. <div class='item-spacer'></div> fn <a href='#tymethod.abs_sub' class='fnname'>abs_sub</a>(self, other: Self) -&gt; Self;
  80. <div class='item-spacer'></div> fn <a href='#tymethod.cbrt' class='fnname'>cbrt</a>(self) -&gt; Self;
  81. <div class='item-spacer'></div> fn <a href='#tymethod.hypot' class='fnname'>hypot</a>(self, other: Self) -&gt; Self;
  82. <div class='item-spacer'></div> fn <a href='#tymethod.sin' class='fnname'>sin</a>(self) -&gt; Self;
  83. <div class='item-spacer'></div> fn <a href='#tymethod.cos' class='fnname'>cos</a>(self) -&gt; Self;
  84. <div class='item-spacer'></div> fn <a href='#tymethod.tan' class='fnname'>tan</a>(self) -&gt; Self;
  85. <div class='item-spacer'></div> fn <a href='#tymethod.asin' class='fnname'>asin</a>(self) -&gt; Self;
  86. <div class='item-spacer'></div> fn <a href='#tymethod.acos' class='fnname'>acos</a>(self) -&gt; Self;
  87. <div class='item-spacer'></div> fn <a href='#tymethod.atan' class='fnname'>atan</a>(self) -&gt; Self;
  88. <div class='item-spacer'></div> fn <a href='#tymethod.atan2' class='fnname'>atan2</a>(self, other: Self) -&gt; Self;
  89. <div class='item-spacer'></div> fn <a href='#tymethod.sin_cos' class='fnname'>sin_cos</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.tuple.html">(</a>Self, Self<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.tuple.html">)</a>;
  90. <div class='item-spacer'></div> fn <a href='#tymethod.exp_m1' class='fnname'>exp_m1</a>(self) -&gt; Self;
  91. <div class='item-spacer'></div> fn <a href='#tymethod.ln_1p' class='fnname'>ln_1p</a>(self) -&gt; Self;
  92. <div class='item-spacer'></div> fn <a href='#tymethod.sinh' class='fnname'>sinh</a>(self) -&gt; Self;
  93. <div class='item-spacer'></div> fn <a href='#tymethod.cosh' class='fnname'>cosh</a>(self) -&gt; Self;
  94. <div class='item-spacer'></div> fn <a href='#tymethod.tanh' class='fnname'>tanh</a>(self) -&gt; Self;
  95. <div class='item-spacer'></div> fn <a href='#tymethod.asinh' class='fnname'>asinh</a>(self) -&gt; Self;
  96. <div class='item-spacer'></div> fn <a href='#tymethod.acosh' class='fnname'>acosh</a>(self) -&gt; Self;
  97. <div class='item-spacer'></div> fn <a href='#tymethod.atanh' class='fnname'>atanh</a>(self) -&gt; Self;
  98. }</pre><div class='docblock'><p>A trait for real number types that do not necessarily have
  99. floating-point-specific characteristics such as NaN and infinity.</p>
  100. <p>See <a href="https://en.wikipedia.org/wiki/Real_data_type">this Wikipedia article</a>
  101. for a list of data types that could meaningfully implement this trait.</p>
  102. <p>This trait is only available with the <code>std</code> feature.</p>
  103. </div>
  104. <h2 id='required-methods' class='small-section-header'>
  105. Required Methods<a href='#required-methods' class='anchor'></a>
  106. </h2>
  107. <div class='methods'>
  108. <h3 id='tymethod.min_value' class='method'><span id='min_value.v' class='invisible'><code>fn <a href='#tymethod.min_value' class='fnname'>min_value</a>() -&gt; Self</code></span></h3><div class='docblock'><p>Returns the smallest finite value that this type can represent.</p>
  109. <pre class="rust rust-example-rendered">
  110. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  111. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  112. <span class="kw">let</span> <span class="ident">x</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="ident">Real</span>::<span class="ident">min_value</span>();
  113. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>, <span class="ident">f64</span>::<span class="ident">MIN</span>);</pre>
  114. </div><h3 id='tymethod.min_positive_value' class='method'><span id='min_positive_value.v' class='invisible'><code>fn <a href='#tymethod.min_positive_value' class='fnname'>min_positive_value</a>() -&gt; Self</code></span></h3><div class='docblock'><p>Returns the smallest positive, normalized value that this type can represent.</p>
  115. <pre class="rust rust-example-rendered">
  116. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  117. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  118. <span class="kw">let</span> <span class="ident">x</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="ident">Real</span>::<span class="ident">min_positive_value</span>();
  119. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>, <span class="ident">f64</span>::<span class="ident">MIN_POSITIVE</span>);</pre>
  120. </div><h3 id='tymethod.epsilon' class='method'><span id='epsilon.v' class='invisible'><code>fn <a href='#tymethod.epsilon' class='fnname'>epsilon</a>() -&gt; Self</code></span></h3><div class='docblock'><p>Returns epsilon, a small positive value.</p>
  121. <pre class="rust rust-example-rendered">
  122. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  123. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  124. <span class="kw">let</span> <span class="ident">x</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="ident">Real</span>::<span class="ident">epsilon</span>();
  125. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>, <span class="ident">f64</span>::<span class="ident">EPSILON</span>);</pre>
  126. <h1 id="panics" class="section-header"><a href="#panics">Panics</a></h1>
  127. <p>The default implementation will panic if <code>f32::EPSILON</code> cannot
  128. be cast to <code>Self</code>.</p>
  129. </div><h3 id='tymethod.max_value' class='method'><span id='max_value.v' class='invisible'><code>fn <a href='#tymethod.max_value' class='fnname'>max_value</a>() -&gt; Self</code></span></h3><div class='docblock'><p>Returns the largest finite value that this type can represent.</p>
  130. <pre class="rust rust-example-rendered">
  131. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  132. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  133. <span class="kw">let</span> <span class="ident">x</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="ident">Real</span>::<span class="ident">max_value</span>();
  134. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>, <span class="ident">f64</span>::<span class="ident">MAX</span>);</pre>
  135. </div><h3 id='tymethod.floor' class='method'><span id='floor.v' class='invisible'><code>fn <a href='#tymethod.floor' class='fnname'>floor</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the largest integer less than or equal to a number.</p>
  136. <pre class="rust rust-example-rendered">
  137. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  138. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">3.99</span>;
  139. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="number">3.0</span>;
  140. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">floor</span>(), <span class="number">3.0</span>);
  141. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">g</span>.<span class="ident">floor</span>(), <span class="number">3.0</span>);</pre>
  142. </div><h3 id='tymethod.ceil' class='method'><span id='ceil.v' class='invisible'><code>fn <a href='#tymethod.ceil' class='fnname'>ceil</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the smallest integer greater than or equal to a number.</p>
  143. <pre class="rust rust-example-rendered">
  144. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  145. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">3.01</span>;
  146. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="number">4.0</span>;
  147. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">ceil</span>(), <span class="number">4.0</span>);
  148. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">g</span>.<span class="ident">ceil</span>(), <span class="number">4.0</span>);</pre>
  149. </div><h3 id='tymethod.round' class='method'><span id='round.v' class='invisible'><code>fn <a href='#tymethod.round' class='fnname'>round</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the nearest integer to a number. Round half-way cases away from
  150. <code>0.0</code>.</p>
  151. <pre class="rust rust-example-rendered">
  152. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  153. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">3.3</span>;
  154. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.3</span>;
  155. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">round</span>(), <span class="number">3.0</span>);
  156. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">g</span>.<span class="ident">round</span>(), <span class="op">-</span><span class="number">3.0</span>);</pre>
  157. </div><h3 id='tymethod.trunc' class='method'><span id='trunc.v' class='invisible'><code>fn <a href='#tymethod.trunc' class='fnname'>trunc</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Return the integer part of a number.</p>
  158. <pre class="rust rust-example-rendered">
  159. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  160. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">3.3</span>;
  161. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.7</span>;
  162. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">trunc</span>(), <span class="number">3.0</span>);
  163. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">g</span>.<span class="ident">trunc</span>(), <span class="op">-</span><span class="number">3.0</span>);</pre>
  164. </div><h3 id='tymethod.fract' class='method'><span id='fract.v' class='invisible'><code>fn <a href='#tymethod.fract' class='fnname'>fract</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the fractional part of a number.</p>
  165. <pre class="rust rust-example-rendered">
  166. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  167. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">3.5</span>;
  168. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.5</span>;
  169. <span class="kw">let</span> <span class="ident">abs_difference_x</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">fract</span>() <span class="op">-</span> <span class="number">0.5</span>).<span class="ident">abs</span>();
  170. <span class="kw">let</span> <span class="ident">abs_difference_y</span> <span class="op">=</span> (<span class="ident">y</span>.<span class="ident">fract</span>() <span class="op">-</span> (<span class="op">-</span><span class="number">0.5</span>)).<span class="ident">abs</span>();
  171. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_x</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  172. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_y</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  173. </div><h3 id='tymethod.abs' class='method'><span id='abs.v' class='invisible'><code>fn <a href='#tymethod.abs' class='fnname'>abs</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the absolute value of <code>self</code>. Returns <code>Float::nan()</code> if the
  174. number is <code>Float::nan()</code>.</p>
  175. <pre class="rust rust-example-rendered">
  176. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  177. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  178. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">3.5</span>;
  179. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.5</span>;
  180. <span class="kw">let</span> <span class="ident">abs_difference_x</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">abs</span>() <span class="op">-</span> <span class="ident">x</span>).<span class="ident">abs</span>();
  181. <span class="kw">let</span> <span class="ident">abs_difference_y</span> <span class="op">=</span> (<span class="ident">y</span>.<span class="ident">abs</span>() <span class="op">-</span> (<span class="op">-</span><span class="ident">y</span>)).<span class="ident">abs</span>();
  182. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_x</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  183. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_y</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  184. <span class="macro">assert</span><span class="macro">!</span>(::<span class="ident">num_traits</span>::<span class="ident">Float</span>::<span class="ident">is_nan</span>(<span class="ident">f64</span>::<span class="ident">NAN</span>.<span class="ident">abs</span>()));</pre>
  185. </div><h3 id='tymethod.signum' class='method'><span id='signum.v' class='invisible'><code>fn <a href='#tymethod.signum' class='fnname'>signum</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns a number that represents the sign of <code>self</code>.</p>
  186. <ul>
  187. <li><code>1.0</code> if the number is positive, <code>+0.0</code> or <code>Float::infinity()</code></li>
  188. <li><code>-1.0</code> if the number is negative, <code>-0.0</code> or <code>Float::neg_infinity()</code></li>
  189. <li><code>Float::nan()</code> if the number is <code>Float::nan()</code></li>
  190. </ul>
  191. <pre class="rust rust-example-rendered">
  192. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  193. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  194. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">3.5</span>;
  195. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">signum</span>(), <span class="number">1.0</span>);
  196. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">f64</span>::<span class="ident">NEG_INFINITY</span>.<span class="ident">signum</span>(), <span class="op">-</span><span class="number">1.0</span>);
  197. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">f64</span>::<span class="ident">NAN</span>.<span class="ident">signum</span>().<span class="ident">is_nan</span>());</pre>
  198. </div><h3 id='tymethod.is_sign_positive' class='method'><span id='is_sign_positive.v' class='invisible'><code>fn <a href='#tymethod.is_sign_positive' class='fnname'>is_sign_positive</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></code></span></h3><div class='docblock'><p>Returns <code>true</code> if <code>self</code> is positive, including <code>+0.0</code>,
  199. <code>Float::infinity()</code>, and with newer versions of Rust <code>f64::NAN</code>.</p>
  200. <pre class="rust rust-example-rendered">
  201. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  202. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  203. <span class="kw">let</span> <span class="ident">neg_nan</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="op">-</span><span class="ident">f64</span>::<span class="ident">NAN</span>;
  204. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">7.0</span>;
  205. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="op">-</span><span class="number">7.0</span>;
  206. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">f</span>.<span class="ident">is_sign_positive</span>());
  207. <span class="macro">assert</span><span class="macro">!</span>(<span class="op">!</span><span class="ident">g</span>.<span class="ident">is_sign_positive</span>());
  208. <span class="macro">assert</span><span class="macro">!</span>(<span class="op">!</span><span class="ident">neg_nan</span>.<span class="ident">is_sign_positive</span>());</pre>
  209. </div><h3 id='tymethod.is_sign_negative' class='method'><span id='is_sign_negative.v' class='invisible'><code>fn <a href='#tymethod.is_sign_negative' class='fnname'>is_sign_negative</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></code></span></h3><div class='docblock'><p>Returns <code>true</code> if <code>self</code> is negative, including <code>-0.0</code>,
  210. <code>Float::neg_infinity()</code>, and with newer versions of Rust <code>-f64::NAN</code>.</p>
  211. <pre class="rust rust-example-rendered">
  212. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  213. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  214. <span class="kw">let</span> <span class="ident">nan</span>: <span class="ident">f64</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">NAN</span>;
  215. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">7.0</span>;
  216. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> <span class="op">-</span><span class="number">7.0</span>;
  217. <span class="macro">assert</span><span class="macro">!</span>(<span class="op">!</span><span class="ident">f</span>.<span class="ident">is_sign_negative</span>());
  218. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">g</span>.<span class="ident">is_sign_negative</span>());
  219. <span class="macro">assert</span><span class="macro">!</span>(<span class="op">!</span><span class="ident">nan</span>.<span class="ident">is_sign_negative</span>());</pre>
  220. </div><h3 id='tymethod.mul_add' class='method'><span id='mul_add.v' class='invisible'><code>fn <a href='#tymethod.mul_add' class='fnname'>mul_add</a>(self, a: Self, b: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Fused multiply-add. Computes <code>(self * a) + b</code> with only one rounding
  221. error. This produces a more accurate result with better performance than
  222. a separate multiplication operation followed by an add.</p>
  223. <pre class="rust rust-example-rendered">
  224. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  225. <span class="kw">let</span> <span class="ident">m</span> <span class="op">=</span> <span class="number">10.0</span>;
  226. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">4.0</span>;
  227. <span class="kw">let</span> <span class="ident">b</span> <span class="op">=</span> <span class="number">60.0</span>;
  228. <span class="comment">// 100.0</span>
  229. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">m</span>.<span class="ident">mul_add</span>(<span class="ident">x</span>, <span class="ident">b</span>) <span class="op">-</span> (<span class="ident">m</span><span class="kw-2">*</span><span class="ident">x</span> <span class="op">+</span> <span class="ident">b</span>)).<span class="ident">abs</span>();
  230. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  231. </div><h3 id='tymethod.recip' class='method'><span id='recip.v' class='invisible'><code>fn <a href='#tymethod.recip' class='fnname'>recip</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Take the reciprocal (inverse) of a number, <code>1/x</code>.</p>
  232. <pre class="rust rust-example-rendered">
  233. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  234. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">2.0</span>;
  235. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">recip</span>() <span class="op">-</span> (<span class="number">1.0</span><span class="op">/</span><span class="ident">x</span>)).<span class="ident">abs</span>();
  236. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  237. </div><h3 id='tymethod.powi' class='method'><span id='powi.v' class='invisible'><code>fn <a href='#tymethod.powi' class='fnname'>powi</a>(self, n: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.i32.html">i32</a>) -&gt; Self</code></span></h3><div class='docblock'><p>Raise a number to an integer power.</p>
  238. <p>Using this function is generally faster than using <code>powf</code></p>
  239. <pre class="rust rust-example-rendered">
  240. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  241. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">2.0</span>;
  242. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">powi</span>(<span class="number">2</span>) <span class="op">-</span> <span class="ident">x</span><span class="kw-2">*</span><span class="ident">x</span>).<span class="ident">abs</span>();
  243. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  244. </div><h3 id='tymethod.powf' class='method'><span id='powf.v' class='invisible'><code>fn <a href='#tymethod.powf' class='fnname'>powf</a>(self, n: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Raise a number to a real number power.</p>
  245. <pre class="rust rust-example-rendered">
  246. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  247. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">2.0</span>;
  248. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">powf</span>(<span class="number">2.0</span>) <span class="op">-</span> <span class="ident">x</span><span class="kw-2">*</span><span class="ident">x</span>).<span class="ident">abs</span>();
  249. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  250. </div><h3 id='tymethod.sqrt' class='method'><span id='sqrt.v' class='invisible'><code>fn <a href='#tymethod.sqrt' class='fnname'>sqrt</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Take the square root of a number.</p>
  251. <p>Returns NaN if <code>self</code> is a negative floating-point number.</p>
  252. <h1 id="panics-1" class="section-header"><a href="#panics-1">Panics</a></h1>
  253. <p>If the implementing type doesn't support NaN, this method should panic if <code>self &lt; 0</code>.</p>
  254. <pre class="rust rust-example-rendered">
  255. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  256. <span class="kw">let</span> <span class="ident">positive</span> <span class="op">=</span> <span class="number">4.0</span>;
  257. <span class="kw">let</span> <span class="ident">negative</span> <span class="op">=</span> <span class="op">-</span><span class="number">4.0</span>;
  258. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">positive</span>.<span class="ident">sqrt</span>() <span class="op">-</span> <span class="number">2.0</span>).<span class="ident">abs</span>();
  259. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  260. <span class="macro">assert</span><span class="macro">!</span>(::<span class="ident">num_traits</span>::<span class="ident">Float</span>::<span class="ident">is_nan</span>(<span class="ident">negative</span>.<span class="ident">sqrt</span>()));</pre>
  261. </div><h3 id='tymethod.exp' class='method'><span id='exp.v' class='invisible'><code>fn <a href='#tymethod.exp' class='fnname'>exp</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns <code>e^(self)</code>, (the exponential function).</p>
  262. <pre class="rust rust-example-rendered">
  263. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  264. <span class="kw">let</span> <span class="ident">one</span> <span class="op">=</span> <span class="number">1.0</span>;
  265. <span class="comment">// e^1</span>
  266. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">one</span>.<span class="ident">exp</span>();
  267. <span class="comment">// ln(e) - 1 == 0</span>
  268. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">e</span>.<span class="ident">ln</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  269. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  270. </div><h3 id='tymethod.exp2' class='method'><span id='exp2.v' class='invisible'><code>fn <a href='#tymethod.exp2' class='fnname'>exp2</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns <code>2^(self)</code>.</p>
  271. <pre class="rust rust-example-rendered">
  272. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  273. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">2.0</span>;
  274. <span class="comment">// 2^2 - 4 == 0</span>
  275. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="ident">exp2</span>() <span class="op">-</span> <span class="number">4.0</span>).<span class="ident">abs</span>();
  276. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  277. </div><h3 id='tymethod.ln' class='method'><span id='ln.v' class='invisible'><code>fn <a href='#tymethod.ln' class='fnname'>ln</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the natural logarithm of the number.</p>
  278. <h1 id="panics-2" class="section-header"><a href="#panics-2">Panics</a></h1>
  279. <p>If <code>self &lt;= 0</code> and this type does not support a NaN representation, this function should panic.</p>
  280. <pre class="rust rust-example-rendered">
  281. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  282. <span class="kw">let</span> <span class="ident">one</span> <span class="op">=</span> <span class="number">1.0</span>;
  283. <span class="comment">// e^1</span>
  284. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">one</span>.<span class="ident">exp</span>();
  285. <span class="comment">// ln(e) - 1 == 0</span>
  286. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">e</span>.<span class="ident">ln</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  287. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  288. </div><h3 id='tymethod.log' class='method'><span id='log.v' class='invisible'><code>fn <a href='#tymethod.log' class='fnname'>log</a>(self, base: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the logarithm of the number with respect to an arbitrary base.</p>
  289. <h1 id="panics-3" class="section-header"><a href="#panics-3">Panics</a></h1>
  290. <p>If <code>self &lt;= 0</code> and this type does not support a NaN representation, this function should panic.</p>
  291. <pre class="rust rust-example-rendered">
  292. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  293. <span class="kw">let</span> <span class="ident">ten</span> <span class="op">=</span> <span class="number">10.0</span>;
  294. <span class="kw">let</span> <span class="ident">two</span> <span class="op">=</span> <span class="number">2.0</span>;
  295. <span class="comment">// log10(10) - 1 == 0</span>
  296. <span class="kw">let</span> <span class="ident">abs_difference_10</span> <span class="op">=</span> (<span class="ident">ten</span>.<span class="ident">log</span>(<span class="number">10.0</span>) <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  297. <span class="comment">// log2(2) - 1 == 0</span>
  298. <span class="kw">let</span> <span class="ident">abs_difference_2</span> <span class="op">=</span> (<span class="ident">two</span>.<span class="ident">log</span>(<span class="number">2.0</span>) <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  299. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_10</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  300. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_2</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  301. </div><h3 id='tymethod.log2' class='method'><span id='log2.v' class='invisible'><code>fn <a href='#tymethod.log2' class='fnname'>log2</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the base 2 logarithm of the number.</p>
  302. <h1 id="panics-4" class="section-header"><a href="#panics-4">Panics</a></h1>
  303. <p>If <code>self &lt;= 0</code> and this type does not support a NaN representation, this function should panic.</p>
  304. <pre class="rust rust-example-rendered">
  305. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  306. <span class="kw">let</span> <span class="ident">two</span> <span class="op">=</span> <span class="number">2.0</span>;
  307. <span class="comment">// log2(2) - 1 == 0</span>
  308. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">two</span>.<span class="ident">log2</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  309. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  310. </div><h3 id='tymethod.log10' class='method'><span id='log10.v' class='invisible'><code>fn <a href='#tymethod.log10' class='fnname'>log10</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the base 10 logarithm of the number.</p>
  311. <h1 id="panics-5" class="section-header"><a href="#panics-5">Panics</a></h1>
  312. <p>If <code>self &lt;= 0</code> and this type does not support a NaN representation, this function should panic.</p>
  313. <pre class="rust rust-example-rendered">
  314. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  315. <span class="kw">let</span> <span class="ident">ten</span> <span class="op">=</span> <span class="number">10.0</span>;
  316. <span class="comment">// log10(10) - 1 == 0</span>
  317. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">ten</span>.<span class="ident">log10</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  318. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  319. </div><h3 id='tymethod.to_degrees' class='method'><span id='to_degrees.v' class='invisible'><code>fn <a href='#tymethod.to_degrees' class='fnname'>to_degrees</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Converts radians to degrees.</p>
  320. <pre class="rust rust-example-rendered">
  321. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>::<span class="ident">consts</span>;
  322. <span class="kw">let</span> <span class="ident">angle</span> <span class="op">=</span> <span class="ident">consts</span>::<span class="ident">PI</span>;
  323. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">angle</span>.<span class="ident">to_degrees</span>() <span class="op">-</span> <span class="number">180.0</span>).<span class="ident">abs</span>();
  324. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  325. </div><h3 id='tymethod.to_radians' class='method'><span id='to_radians.v' class='invisible'><code>fn <a href='#tymethod.to_radians' class='fnname'>to_radians</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Converts degrees to radians.</p>
  326. <pre class="rust rust-example-rendered">
  327. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>::<span class="ident">consts</span>;
  328. <span class="kw">let</span> <span class="ident">angle</span> <span class="op">=</span> <span class="number">180.0_f64</span>;
  329. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">angle</span>.<span class="ident">to_radians</span>() <span class="op">-</span> <span class="ident">consts</span>::<span class="ident">PI</span>).<span class="ident">abs</span>();
  330. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  331. </div><h3 id='tymethod.max' class='method'><span id='max.v' class='invisible'><code>fn <a href='#tymethod.max' class='fnname'>max</a>(self, other: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the maximum of the two numbers.</p>
  332. <pre class="rust rust-example-rendered">
  333. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  334. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  335. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="number">2.0</span>;
  336. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>.<span class="ident">max</span>(<span class="ident">y</span>), <span class="ident">y</span>);</pre>
  337. </div><h3 id='tymethod.min' class='method'><span id='min.v' class='invisible'><code>fn <a href='#tymethod.min' class='fnname'>min</a>(self, other: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns the minimum of the two numbers.</p>
  338. <pre class="rust rust-example-rendered">
  339. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  340. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  341. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="number">2.0</span>;
  342. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>.<span class="ident">min</span>(<span class="ident">y</span>), <span class="ident">x</span>);</pre>
  343. </div><h3 id='tymethod.abs_sub' class='method'><span id='abs_sub.v' class='invisible'><code>fn <a href='#tymethod.abs_sub' class='fnname'>abs_sub</a>(self, other: Self) -&gt; Self</code></span></h3><div class='docblock'><p>The positive difference of two numbers.</p>
  344. <ul>
  345. <li>If <code>self &lt;= other</code>: <code>0:0</code></li>
  346. <li>Else: <code>self - other</code></li>
  347. </ul>
  348. <pre class="rust rust-example-rendered">
  349. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  350. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">3.0</span>;
  351. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.0</span>;
  352. <span class="kw">let</span> <span class="ident">abs_difference_x</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">abs_sub</span>(<span class="number">1.0</span>) <span class="op">-</span> <span class="number">2.0</span>).<span class="ident">abs</span>();
  353. <span class="kw">let</span> <span class="ident">abs_difference_y</span> <span class="op">=</span> (<span class="ident">y</span>.<span class="ident">abs_sub</span>(<span class="number">1.0</span>) <span class="op">-</span> <span class="number">0.0</span>).<span class="ident">abs</span>();
  354. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_x</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  355. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_y</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  356. </div><h3 id='tymethod.cbrt' class='method'><span id='cbrt.v' class='invisible'><code>fn <a href='#tymethod.cbrt' class='fnname'>cbrt</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Take the cubic root of a number.</p>
  357. <pre class="rust rust-example-rendered">
  358. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  359. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">8.0</span>;
  360. <span class="comment">// x^(1/3) - 2 == 0</span>
  361. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">cbrt</span>() <span class="op">-</span> <span class="number">2.0</span>).<span class="ident">abs</span>();
  362. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  363. </div><h3 id='tymethod.hypot' class='method'><span id='hypot.v' class='invisible'><code>fn <a href='#tymethod.hypot' class='fnname'>hypot</a>(self, other: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Calculate the length of the hypotenuse of a right-angle triangle given
  364. legs of length <code>x</code> and <code>y</code>.</p>
  365. <pre class="rust rust-example-rendered">
  366. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  367. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">2.0</span>;
  368. <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="number">3.0</span>;
  369. <span class="comment">// sqrt(x^2 + y^2)</span>
  370. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">hypot</span>(<span class="ident">y</span>) <span class="op">-</span> (<span class="ident">x</span>.<span class="ident">powi</span>(<span class="number">2</span>) <span class="op">+</span> <span class="ident">y</span>.<span class="ident">powi</span>(<span class="number">2</span>)).<span class="ident">sqrt</span>()).<span class="ident">abs</span>();
  371. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  372. </div><h3 id='tymethod.sin' class='method'><span id='sin.v' class='invisible'><code>fn <a href='#tymethod.sin' class='fnname'>sin</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the sine of a number (in radians).</p>
  373. <pre class="rust rust-example-rendered">
  374. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  375. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  376. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span><span class="op">/</span><span class="number">2.0</span>;
  377. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">sin</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  378. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  379. </div><h3 id='tymethod.cos' class='method'><span id='cos.v' class='invisible'><code>fn <a href='#tymethod.cos' class='fnname'>cos</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the cosine of a number (in radians).</p>
  380. <pre class="rust rust-example-rendered">
  381. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  382. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  383. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">2.0</span><span class="kw-2">*</span><span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span>;
  384. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">cos</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  385. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  386. </div><h3 id='tymethod.tan' class='method'><span id='tan.v' class='invisible'><code>fn <a href='#tymethod.tan' class='fnname'>tan</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the tangent of a number (in radians).</p>
  387. <pre class="rust rust-example-rendered">
  388. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  389. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  390. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span><span class="op">/</span><span class="number">4.0</span>;
  391. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">tan</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  392. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-14</span>);</pre>
  393. </div><h3 id='tymethod.asin' class='method'><span id='asin.v' class='invisible'><code>fn <a href='#tymethod.asin' class='fnname'>asin</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the arcsine of a number. Return value is in radians in
  394. the range [-pi/2, pi/2] or NaN if the number is outside the range
  395. [-1, 1].</p>
  396. <h1 id="panics-6" class="section-header"><a href="#panics-6">Panics</a></h1>
  397. <p>If this type does not support a NaN representation, this function should panic
  398. if the number is outside the range [-1, 1].</p>
  399. <pre class="rust rust-example-rendered">
  400. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  401. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  402. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span> <span class="op">/</span> <span class="number">2.0</span>;
  403. <span class="comment">// asin(sin(pi/2))</span>
  404. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="ident">sin</span>().<span class="ident">asin</span>() <span class="op">-</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span> <span class="op">/</span> <span class="number">2.0</span>).<span class="ident">abs</span>();
  405. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  406. </div><h3 id='tymethod.acos' class='method'><span id='acos.v' class='invisible'><code>fn <a href='#tymethod.acos' class='fnname'>acos</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the arccosine of a number. Return value is in radians in
  407. the range [0, pi] or NaN if the number is outside the range
  408. [-1, 1].</p>
  409. <h1 id="panics-7" class="section-header"><a href="#panics-7">Panics</a></h1>
  410. <p>If this type does not support a NaN representation, this function should panic
  411. if the number is outside the range [-1, 1].</p>
  412. <pre class="rust rust-example-rendered">
  413. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  414. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  415. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span> <span class="op">/</span> <span class="number">4.0</span>;
  416. <span class="comment">// acos(cos(pi/4))</span>
  417. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="ident">cos</span>().<span class="ident">acos</span>() <span class="op">-</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span> <span class="op">/</span> <span class="number">4.0</span>).<span class="ident">abs</span>();
  418. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  419. </div><h3 id='tymethod.atan' class='method'><span id='atan.v' class='invisible'><code>fn <a href='#tymethod.atan' class='fnname'>atan</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the arctangent of a number. Return value is in radians in the
  420. range [-pi/2, pi/2];</p>
  421. <pre class="rust rust-example-rendered">
  422. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  423. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="number">1.0</span>;
  424. <span class="comment">// atan(tan(1))</span>
  425. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="ident">tan</span>().<span class="ident">atan</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  426. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  427. </div><h3 id='tymethod.atan2' class='method'><span id='atan2.v' class='invisible'><code>fn <a href='#tymethod.atan2' class='fnname'>atan2</a>(self, other: Self) -&gt; Self</code></span></h3><div class='docblock'><p>Computes the four quadrant arctangent of <code>self</code> (<code>y</code>) and <code>other</code> (<code>x</code>).</p>
  428. <ul>
  429. <li><code>x = 0</code>, <code>y = 0</code>: <code>0</code></li>
  430. <li><code>x &gt;= 0</code>: <code>arctan(y/x)</code> -&gt; <code>[-pi/2, pi/2]</code></li>
  431. <li><code>y &gt;= 0</code>: <code>arctan(y/x) + pi</code> -&gt; <code>(pi/2, pi]</code></li>
  432. <li><code>y &lt; 0</code>: <code>arctan(y/x) - pi</code> -&gt; <code>(-pi, -pi/2)</code></li>
  433. </ul>
  434. <pre class="rust rust-example-rendered">
  435. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  436. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  437. <span class="kw">let</span> <span class="ident">pi</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span>;
  438. <span class="comment">// All angles from horizontal right (+x)</span>
  439. <span class="comment">// 45 deg counter-clockwise</span>
  440. <span class="kw">let</span> <span class="ident">x1</span> <span class="op">=</span> <span class="number">3.0</span>;
  441. <span class="kw">let</span> <span class="ident">y1</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.0</span>;
  442. <span class="comment">// 135 deg clockwise</span>
  443. <span class="kw">let</span> <span class="ident">x2</span> <span class="op">=</span> <span class="op">-</span><span class="number">3.0</span>;
  444. <span class="kw">let</span> <span class="ident">y2</span> <span class="op">=</span> <span class="number">3.0</span>;
  445. <span class="kw">let</span> <span class="ident">abs_difference_1</span> <span class="op">=</span> (<span class="ident">y1</span>.<span class="ident">atan2</span>(<span class="ident">x1</span>) <span class="op">-</span> (<span class="op">-</span><span class="ident">pi</span><span class="op">/</span><span class="number">4.0</span>)).<span class="ident">abs</span>();
  446. <span class="kw">let</span> <span class="ident">abs_difference_2</span> <span class="op">=</span> (<span class="ident">y2</span>.<span class="ident">atan2</span>(<span class="ident">x2</span>) <span class="op">-</span> <span class="number">3.0</span><span class="kw-2">*</span><span class="ident">pi</span><span class="op">/</span><span class="number">4.0</span>).<span class="ident">abs</span>();
  447. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_1</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  448. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_2</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  449. </div><h3 id='tymethod.sin_cos' class='method'><span id='sin_cos.v' class='invisible'><code>fn <a href='#tymethod.sin_cos' class='fnname'>sin_cos</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.tuple.html">(</a>Self, Self<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.tuple.html">)</a></code></span></h3><div class='docblock'><p>Simultaneously computes the sine and cosine of the number, <code>x</code>. Returns
  450. <code>(sin(x), cos(x))</code>.</p>
  451. <pre class="rust rust-example-rendered">
  452. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  453. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  454. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">PI</span><span class="op">/</span><span class="number">4.0</span>;
  455. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">sin_cos</span>();
  456. <span class="kw">let</span> <span class="ident">abs_difference_0</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="number">0</span> <span class="op">-</span> <span class="ident">x</span>.<span class="ident">sin</span>()).<span class="ident">abs</span>();
  457. <span class="kw">let</span> <span class="ident">abs_difference_1</span> <span class="op">=</span> (<span class="ident">f</span>.<span class="number">1</span> <span class="op">-</span> <span class="ident">x</span>.<span class="ident">cos</span>()).<span class="ident">abs</span>();
  458. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_0</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);
  459. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference_0</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  460. </div><h3 id='tymethod.exp_m1' class='method'><span id='exp_m1.v' class='invisible'><code>fn <a href='#tymethod.exp_m1' class='fnname'>exp_m1</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns <code>e^(self) - 1</code> in a way that is accurate even if the
  461. number is close to zero.</p>
  462. <pre class="rust rust-example-rendered">
  463. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  464. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">7.0</span>;
  465. <span class="comment">// e^(ln(7)) - 1</span>
  466. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">ln</span>().<span class="ident">exp_m1</span>() <span class="op">-</span> <span class="number">6.0</span>).<span class="ident">abs</span>();
  467. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  468. </div><h3 id='tymethod.ln_1p' class='method'><span id='ln_1p.v' class='invisible'><code>fn <a href='#tymethod.ln_1p' class='fnname'>ln_1p</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Returns <code>ln(1+n)</code> (natural logarithm) more accurately than if
  469. the operations were performed separately.</p>
  470. <h1 id="panics-8" class="section-header"><a href="#panics-8">Panics</a></h1>
  471. <p>If this type does not support a NaN representation, this function should panic
  472. if <code>self-1 &lt;= 0</code>.</p>
  473. <pre class="rust rust-example-rendered">
  474. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  475. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  476. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">E</span> <span class="op">-</span> <span class="number">1.0</span>;
  477. <span class="comment">// ln(1 + (e - 1)) == ln(e) == 1</span>
  478. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">x</span>.<span class="ident">ln_1p</span>() <span class="op">-</span> <span class="number">1.0</span>).<span class="ident">abs</span>();
  479. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  480. </div><h3 id='tymethod.sinh' class='method'><span id='sinh.v' class='invisible'><code>fn <a href='#tymethod.sinh' class='fnname'>sinh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Hyperbolic sine function.</p>
  481. <pre class="rust rust-example-rendered">
  482. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  483. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  484. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">E</span>;
  485. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  486. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">sinh</span>();
  487. <span class="comment">// Solving sinh() at 1 gives `(e^2-1)/(2e)`</span>
  488. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> (<span class="ident">e</span><span class="kw-2">*</span><span class="ident">e</span> <span class="op">-</span> <span class="number">1.0</span>)<span class="op">/</span>(<span class="number">2.0</span><span class="kw-2">*</span><span class="ident">e</span>);
  489. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">g</span>).<span class="ident">abs</span>();
  490. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1e-10</span>);</pre>
  491. </div><h3 id='tymethod.cosh' class='method'><span id='cosh.v' class='invisible'><code>fn <a href='#tymethod.cosh' class='fnname'>cosh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Hyperbolic cosine function.</p>
  492. <pre class="rust rust-example-rendered">
  493. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  494. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  495. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">E</span>;
  496. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  497. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">cosh</span>();
  498. <span class="comment">// Solving cosh() at 1 gives this result</span>
  499. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> (<span class="ident">e</span><span class="kw-2">*</span><span class="ident">e</span> <span class="op">+</span> <span class="number">1.0</span>)<span class="op">/</span>(<span class="number">2.0</span><span class="kw-2">*</span><span class="ident">e</span>);
  500. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">g</span>).<span class="ident">abs</span>();
  501. <span class="comment">// Same result</span>
  502. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1.0e-10</span>);</pre>
  503. </div><h3 id='tymethod.tanh' class='method'><span id='tanh.v' class='invisible'><code>fn <a href='#tymethod.tanh' class='fnname'>tanh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Hyperbolic tangent function.</p>
  504. <pre class="rust rust-example-rendered">
  505. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  506. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  507. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">E</span>;
  508. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  509. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">tanh</span>();
  510. <span class="comment">// Solving tanh() at 1 gives `(1 - e^(-2))/(1 + e^(-2))`</span>
  511. <span class="kw">let</span> <span class="ident">g</span> <span class="op">=</span> (<span class="number">1.0</span> <span class="op">-</span> <span class="ident">e</span>.<span class="ident">powi</span>(<span class="op">-</span><span class="number">2</span>))<span class="op">/</span>(<span class="number">1.0</span> <span class="op">+</span> <span class="ident">e</span>.<span class="ident">powi</span>(<span class="op">-</span><span class="number">2</span>));
  512. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">g</span>).<span class="ident">abs</span>();
  513. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1.0e-10</span>);</pre>
  514. </div><h3 id='tymethod.asinh' class='method'><span id='asinh.v' class='invisible'><code>fn <a href='#tymethod.asinh' class='fnname'>asinh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Inverse hyperbolic sine function.</p>
  515. <pre class="rust rust-example-rendered">
  516. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  517. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  518. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">sinh</span>().<span class="ident">asinh</span>();
  519. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">x</span>).<span class="ident">abs</span>();
  520. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1.0e-10</span>);</pre>
  521. </div><h3 id='tymethod.acosh' class='method'><span id='acosh.v' class='invisible'><code>fn <a href='#tymethod.acosh' class='fnname'>acosh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Inverse hyperbolic cosine function.</p>
  522. <pre class="rust rust-example-rendered">
  523. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  524. <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">1.0</span>;
  525. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">cosh</span>().<span class="ident">acosh</span>();
  526. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">x</span>).<span class="ident">abs</span>();
  527. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1.0e-10</span>);</pre>
  528. </div><h3 id='tymethod.atanh' class='method'><span id='atanh.v' class='invisible'><code>fn <a href='#tymethod.atanh' class='fnname'>atanh</a>(self) -&gt; Self</code></span></h3><div class='docblock'><p>Inverse hyperbolic tangent function.</p>
  529. <pre class="rust rust-example-rendered">
  530. <span class="kw">use</span> <span class="ident">num_traits</span>::<span class="ident">real</span>::<span class="ident">Real</span>;
  531. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">f64</span>;
  532. <span class="kw">let</span> <span class="ident">e</span> <span class="op">=</span> <span class="ident">f64</span>::<span class="ident">consts</span>::<span class="ident">E</span>;
  533. <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">e</span>.<span class="ident">tanh</span>().<span class="ident">atanh</span>();
  534. <span class="kw">let</span> <span class="ident">abs_difference</span> <span class="op">=</span> (<span class="ident">f</span> <span class="op">-</span> <span class="ident">e</span>).<span class="ident">abs</span>();
  535. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">abs_difference</span> <span class="op">&lt;</span> <span class="number">1.0e-10</span>);</pre>
  536. </div></div>
  537. <h2 id='implementors' class='small-section-header'>
  538. Implementors<a href='#implementors' class='anchor'></a>
  539. </h2>
  540. <ul class='item-list' id='implementors-list'>
  541. <li><div class='out-of-band'><a class='srclink' href='../../src/num_traits/real.rs.html#784-836' title='goto source code'>[src]</a></div><code>impl&lt;T&gt; Real for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;T: <a class="trait" href="../../num_traits/float/trait.Float.html" title="trait num_traits::float::Float">Float</a>,&nbsp;</span></code></li>
  542. </ul><script type="text/javascript" async
  543. src="../../implementors/num_traits/real/trait.Real.js">
  544. </script></section>
  545. <section id='search' class="content hidden"></section>
  546. <section class="footer"></section>
  547. <aside id="help" class="hidden">
  548. <div>
  549. <h1 class="hidden">Help</h1>
  550. <div class="shortcuts">
  551. <h2>Keyboard Shortcuts</h2>
  552. <dl>
  553. <dt><kbd>?</kbd></dt>
  554. <dd>Show this help dialog</dd>
  555. <dt><kbd>S</kbd></dt>
  556. <dd>Focus the search field</dd>
  557. <dt><kbd>↑</kbd></dt>
  558. <dd>Move up in search results</dd>
  559. <dt><kbd>↓</kbd></dt>
  560. <dd>Move down in search results</dd>
  561. <dt><kbd>↹</kbd></dt>
  562. <dd>Switch tab</dd>
  563. <dt><kbd>&#9166;</kbd></dt>
  564. <dd>Go to active search result</dd>
  565. <dt><kbd>+</kbd></dt>
  566. <dd>Expand all sections</dd>
  567. <dt><kbd>-</kbd></dt>
  568. <dd>Collapse all sections</dd>
  569. </dl>
  570. </div>
  571. <div class="infos">
  572. <h2>Search Tricks</h2>
  573. <p>
  574. Prefix searches with a type followed by a colon (e.g.
  575. <code>fn:</code>) to restrict the search to a given type.
  576. </p>
  577. <p>
  578. Accepted types are: <code>fn</code>, <code>mod</code>,
  579. <code>struct</code>, <code>enum</code>,
  580. <code>trait</code>, <code>type</code>, <code>macro</code>,
  581. and <code>const</code>.
  582. </p>
  583. <p>
  584. Search functions by type signature (e.g.
  585. <code>vec -> usize</code> or <code>* -> vec</code>)
  586. </p>
  587. </div>
  588. </div>
  589. </aside>
  590. <script>
  591. window.rootPath = "../../";
  592. window.currentCrate = "num_traits";
  593. </script>
  594. <script src="../../main.js"></script>
  595. <script defer src="../../search-index.js"></script>
  596. </body>
  597. </html>