1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Std copy</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="Chapter 1. Boost.Icl"> 8<link rel="up" href="../examples.html" title="Examples"> 9<link rel="prev" href="user_groups.html" title="User groups"> 10<link rel="next" href="std_transform.html" title="Std transform"> 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="../../../../../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="user_groups.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../examples.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="std_transform.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="boost_icl.examples.std_copy"></a><a class="link" href="std_copy.html" title="Std copy">Std copy</a> 28</h3></div></div></div> 29<p> 30 The standard algorithm <a href="http://www.cplusplus.com/reference/algorithm/copy/" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code></a> 31 can be used to fill interval containers from standard containers of intervals 32 or interval value pairs (segments). Because intervals do not represent <span class="emphasis"><em><span class="bold"><strong>elements</strong></span></em></span> but <span class="emphasis"><em><span class="bold"><strong>sets</strong></span></em></span>, 33 that can be empty or contain more than one element, the usage of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code> 34 differs from what we are familiar with using <span class="emphasis"><em>containers of elements</em></span>. 35 </p> 36<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 37<li class="listitem"> 38 Use <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span></code> from <code class="computeroutput"><span class="preprocessor">#include</span> 39 <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">icl</span><span class="special">/</span><span class="identifier">iterator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> instead of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">inserter</span></code> 40 to call insertions on the target interval container. 41 </li> 42<li class="listitem"> 43 As shown in the examples above and below this point, most of the time 44 we will not be interested to <code class="computeroutput"><span class="identifier">insert</span></code> 45 segments into <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_maps</a></code> 46 but to <a class="link" href="../function_reference/addition.html" title="Addition"><span class="emphasis"><em><span class="bold"><strong>add</strong></span></em></span></a> them, in order to generate 47 the desired aggregation results. You can use <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code> 48 with an <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">adder</span></code> instead of an <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span></code> 49 to achieve this. 50 </li> 51</ul></div> 52<p> 53</p> 54<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> 55<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">vector</span><span class="special">></span> 56<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">algorithm</span><span class="special">></span> 57<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">icl</span><span class="special">/</span><span class="identifier">interval_map</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 58 59<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">std</span><span class="special">;</span> 60<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">;</span> 61<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">icl</span><span class="special">;</span> 62 63<span class="comment">// 'make_segments' returns a vector of interval value pairs, which</span> 64<span class="comment">// are not sorted. The values are taken from the minimal example</span> 65<span class="comment">// in section 'interval combining styles'.</span> 66<span class="identifier">vector</span><span class="special"><</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">></span> <span class="identifier">make_segments</span><span class="special">()</span> 67<span class="special">{</span> 68 <span class="identifier">vector</span><span class="special"><</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">></span> <span class="identifier">segment_vec</span><span class="special">;</span> 69 <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="number">4</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span> 70 <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">4</span><span class="special">,</span><span class="number">5</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span> 71 <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">3</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span> 72 <span class="keyword">return</span> <span class="identifier">segment_vec</span><span class="special">;</span> 73<span class="special">}</span> 74 75<span class="comment">// 'show_segments' displays the source segements.</span> 76<span class="keyword">void</span> <span class="identifier">show_segments</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">vector</span><span class="special"><</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">>&</span> <span class="identifier">segments</span><span class="special">)</span> 77<span class="special">{</span> 78 <span class="identifier">vector</span><span class="special"><</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">>::</span><span class="identifier">const_iterator</span> <span class="identifier">iter</span> <span class="special">=</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">();</span> 79 <span class="keyword">while</span><span class="special">(</span><span class="identifier">iter</span> <span class="special">!=</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">())</span> 80 <span class="special">{</span> 81 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"("</span> <span class="special"><<</span> <span class="identifier">iter</span><span class="special">-></span><span class="identifier">first</span> <span class="special"><<</span> <span class="string">","</span> <span class="special"><<</span> <span class="identifier">iter</span><span class="special">-></span><span class="identifier">second</span> <span class="special"><<</span> <span class="string">")"</span><span class="special">;</span> 82 <span class="special">++</span><span class="identifier">iter</span><span class="special">;</span> 83 <span class="special">}</span> 84<span class="special">}</span> 85 86<span class="keyword">void</span> <span class="identifier">std_copy</span><span class="special">()</span> 87<span class="special">{</span> 88 <span class="comment">// So we have some segments stored in an std container.</span> 89 <span class="identifier">vector</span><span class="special"><</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">discrete_interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">></span> <span class="identifier">segments</span> <span class="special">=</span> <span class="identifier">make_segments</span><span class="special">();</span> 90 <span class="comment">// Display the input</span> 91 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"input sequence: "</span><span class="special">;</span> <span class="identifier">show_segments</span><span class="special">(</span><span class="identifier">segments</span><span class="special">);</span> <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n\n"</span><span class="special">;</span> 92 93 <span class="comment">// We are going to 'std::copy' those segments into an interval_map:</span> 94 <span class="identifier">interval_map</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">segmap</span><span class="special">;</span> 95 96 <span class="comment">// Use an 'icl::inserter' from <boost/icl/iterator.hpp> to call </span> 97 <span class="comment">// insertion on the interval container.</span> 98 <span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span><span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> 99 <span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span><span class="special">(</span><span class="identifier">segmap</span><span class="special">,</span> <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">end</span><span class="special">()));</span> 100 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"icl::inserting: "</span> <span class="special"><<</span> <span class="identifier">segmap</span> <span class="special"><<</span> <span class="identifier">endl</span><span class="special">;</span> 101 <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span> 102 103 <span class="comment">// When we are feeding data into interval_maps, most of the time we are</span> 104 <span class="comment">// intending to compute an aggregation result. So we are not interested</span> 105 <span class="comment">// the std::insert semantincs but the aggregating icl::addition semantics.</span> 106 <span class="comment">// To achieve this there is an icl::add_iterator and an icl::adder function </span> 107 <span class="comment">// provided in <boost/icl/iterator.hpp>.</span> 108 <span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span><span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> 109 <span class="identifier">icl</span><span class="special">::</span><span class="identifier">adder</span><span class="special">(</span><span class="identifier">segmap</span><span class="special">,</span> <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">end</span><span class="special">()));</span> <span class="comment">//Aggregating associated values</span> 110 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"icl::adding : "</span> <span class="special"><<</span> <span class="identifier">segmap</span> <span class="special"><<</span> <span class="identifier">endl</span><span class="special">;</span> 111 112 <span class="comment">// In this last case, the semantics of 'std::copy' transforms to the </span> 113 <span class="comment">// generalized addition operation, that is implemented by operator</span> 114 <span class="comment">// += or + on itl maps and sets.</span> 115<span class="special">}</span> 116 117<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> 118<span class="special">{</span> 119 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">">> Interval Container Library: Example std_copy.cpp <<\n"</span><span class="special">;</span> 120 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"-----------------------------------------------------------\n"</span><span class="special">;</span> 121 <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Using std::copy to fill an interval_map:\n\n"</span><span class="special">;</span> 122 123 <span class="identifier">std_copy</span><span class="special">();</span> 124 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 125<span class="special">}</span> 126 127<span class="comment">// Program output:</span> 128<span class="comment">/*--------------------------------------------------------- 129>> Interval Container Library: Example std_copy.cpp << 130----------------------------------------------------------- 131Using std::copy to fill an interval_map: 132 133input sequence: ([2,4),1)([4,5),1)([1,3),1) 134 135icl::inserting: {([1,5)->1)} 136icl::adding : {([1,2)->1)([2,3)->2)([3,5)->1)} 137---------------------------------------------------------*/</span> 138</pre> 139<p> 140 </p> 141</div> 142<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 143<td align="left"></td> 144<td align="right"><div class="copyright-footer">Copyright © 2007-2010 Joachim 145 Faulhaber<br>Copyright © 1999-2006 Cortex Software 146 GmbH<p> 147 Distributed under the Boost Software License, Version 1.0. (See accompanying 148 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>) 149 </p> 150</div></td> 151</tr></table> 152<hr> 153<div class="spirit-nav"> 154<a accesskey="p" href="user_groups.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../examples.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="std_transform.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 155</div> 156</body> 157</html> 158
