1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Cost of High-Precision Non-built-in Floating-point</title> 5<link rel="stylesheet" href="../math.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../index.html" title="Math Toolkit 2.12.0"> 8<link rel="up" href="../perf.html" title="Chapter 22. Performance"> 9<link rel="prev" href="tradoffs.html" title="Trading Accuracy for Performance"> 10<link rel="next" href="tuning.html" title="Performance Tuning Macros"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="tradoffs.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../perf.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="tuning.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h2 class="title" style="clear: both"> 27<a name="math_toolkit.multiprecision"></a><a class="link" href="multiprecision.html" title="Cost of High-Precision Non-built-in Floating-point">Cost of High-Precision Non-built-in 28 Floating-point</a> 29</h2></div></div></div> 30<p> 31 Using user-defined floating-point like <a href="../../../../../libs/multiprecision/doc/html/index.html" target="_top">Boost.Multiprecision</a> 32 has a very high run-time cost. 33 </p> 34<p> 35 To give some flavour of this: 36 </p> 37<div class="table"> 38<a name="math_toolkit.multiprecision.linpack_time"></a><p class="title"><b>Table 22.3. Linpack Benchmark</b></p> 39<div class="table-contents"><table class="table" summary="Linpack Benchmark"> 40<colgroup> 41<col> 42<col> 43</colgroup> 44<thead><tr> 45<th> 46 <p> 47 floating-point type 48 </p> 49 </th> 50<th> 51 <p> 52 speed Mflops 53 </p> 54 </th> 55</tr></thead> 56<tbody> 57<tr> 58<td> 59 <p> 60 double 61 </p> 62 </td> 63<td> 64 <p> 65 2727 66 </p> 67 </td> 68</tr> 69<tr> 70<td> 71 <p> 72 __float128 73 </p> 74 </td> 75<td> 76 <p> 77 35 78 </p> 79 </td> 80</tr> 81<tr> 82<td> 83 <p> 84 multiprecision::float128 85 </p> 86 </td> 87<td> 88 <p> 89 35 90 </p> 91 </td> 92</tr> 93<tr> 94<td> 95 <p> 96 multiprecision::cpp_bin_float_quad 97 </p> 98 </td> 99<td> 100 <p> 101 6 102 </p> 103 </td> 104</tr> 105</tbody> 106</table></div> 107</div> 108<br class="table-break"> 109</div> 110<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 111<td align="left"></td> 112<td align="right"><div class="copyright-footer">Copyright © 2006-2019 Nikhar 113 Agrawal, Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos, 114 Hubert Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Matthew Pulver, Johan 115 Råde, Gautam Sewani, Benjamin Sobotta, Nicholas Thompson, Thijs van den Berg, 116 Daryle Walker and Xiaogang Zhang<p> 117 Distributed under the Boost Software License, Version 1.0. (See accompanying 118 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 119 </p> 120</div></td> 121</tr></table> 122<hr> 123<div class="spirit-nav"> 124<a accesskey="p" href="tradoffs.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../perf.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="tuning.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 125</div> 126</body> 127</html> 128
