1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Integer Sort</title> 5<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../../index.html" title="Boost.Sort"> 8<link rel="up" href="../sort_hpp.html" title="Spreadsort"> 9<link rel="prev" href="../sort_hpp.html" title="Spreadsort"> 10<link rel="next" href="float_sort.html" title="Float Sort"> 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="../sort_hpp.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../sort_hpp.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="float_sort.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="sort.single_thread.spreadsort.sort_hpp.integer_sort"></a><a class="link" href="integer_sort.html" title="Integer Sort">Integer 28 Sort</a> 29</h5></div></div></div> 30<p> 31 <code class="literal"><code class="computeroutput"><a class="link" href="../../../../boost/sort/spreadsort/integer__idm45878544022768.html" title="Function template integer_sort">integer_sort</a></code></code> 32 is a fast templated in-place hybrid radix/comparison algorithm, which 33 in testing tends to be roughly 50% to 2X faster than <a href="http://en.cppreference.com/w/cpp/algorithm/sort" target="_top">std::sort</a> 34 for large tests (>=100kB). Worst-case performance is <span class="emphasis"><em>��(N 35 * (log2(range)/s + s))</em></span>, so <code class="literal"><code class="computeroutput"><a class="link" href="../../../../boost/sort/spreadsort/integer__idm45878544022768.html" title="Function template integer_sort">integer_sort</a></code></code> 36 is asymptotically faster than pure comparison-based algorithms. <span class="emphasis"><em>s</em></span> 37 is <span class="emphasis"><em>max_splits</em></span>, which defaults to 11, so its worst-case 38 with default settings for 32-bit integers is <span class="emphasis"><em>��(N * ((32/11)</em></span> 39 slow radix-based iterations + 11 fast comparison-based iterations). 40 </p> 41<p> 42 Some performance plots of runtime vs. n and log2(range) are provided 43 below: 44 </p> 45<p> 46 <a href="../../../../../../doc/graph/windows_integer_sort.htm" target="_top">Windows Integer 47 Sort</a> 48 </p> 49<p> 50 <a href="../../../../../../doc/graph/osx_integer_sort.htm" target="_top">OSX integer Sort</a> 51 </p> 52<div class="section"> 53<div class="titlepage"><div><div><h6 class="title"> 54<a name="sort.single_thread.spreadsort.sort_hpp.integer_sort.integersort_examples"></a><a class="link" href="integer_sort.html#sort.single_thread.spreadsort.sort_hpp.integer_sort.integersort_examples" title="Integer Sort Examples">Integer 55 Sort Examples</a> 56</h6></div></div></div> 57<p> 58 See <a href="../../../../../../example/rightshiftsample.cpp" target="_top">rightshiftsample.cpp</a> 59 for a working example of using rightshift, using a user-defined functor: 60 </p> 61<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">rightshift</span> <span class="special">{</span> 62 <span class="keyword">inline</span> <span class="keyword">int</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">DATA_TYPE</span> <span class="identifier">x</span><span class="special">,</span> <span class="keyword">unsigned</span> <span class="identifier">offset</span><span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">x</span> <span class="special">>></span> <span class="identifier">offset</span><span class="special">;</span> <span class="special">}</span> 63<span class="special">};</span> 64</pre> 65<p> 66 Other examples: 67 </p> 68<p> 69 <a href="../../../../../../example/keyplusdatasample.cpp" target="_top">Sort structs using 70 an integer key.</a> 71 </p> 72<p> 73 <a href="../../../../../../example/reverseintsample.cpp" target="_top">Sort integers in reverse 74 order.</a> 75 </p> 76<p> 77 <a href="../../../../../../example/mostlysorted.cpp" target="_top">Simple sorting of integers; 78 this case is a performance test for integers that are already mostly 79 sorted.</a> 80 </p> 81</div> 82</div> 83<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 84<td align="left"></td> 85<td align="right"><div class="copyright-footer">Copyright © 2014-2017 Steven 86 Ross, Francisco Tapia, Orson Peters<p> 87 Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost 88 Software License, Version 1.0</a>. 89 </p> 90</div></td> 91</tr></table> 92<hr> 93<div class="spirit-nav"> 94<a accesskey="p" href="../sort_hpp.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../sort_hpp.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="float_sort.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 95</div> 96</body> 97</html> 98
