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  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__idm46048203222928.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 (&gt;=100kB). Worst-case performance is <span class="emphasis"><em>&#119926;(N
  35             * (log2(range)/s + s))</em></span>, so <code class="literal"><code class="computeroutput"><a class="link" href="../../../../boost/sort/spreadsort/integer__idm46048203222928.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>&#119926;(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">&gt;&gt;</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>
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  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>.
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