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| 24 | </div> | |
| 25 | <div class="section boost_icl_implementation" lang="en"> | |
| 26 | <div class="titlepage"><div><div><h2 class="title" style="clear: both"> | |
| 27 | <a name="boost_icl.implementation"></a><a class="link" href="implementation.html" title="Implementation">Implementation</a> | |
| 28 | </h2></div></div></div> | |
| 29 | <div class="toc"><dl> | |
| 30 | <dt><span class="section"><a href="implementation.html#boost_icl.implementation.iterative_size">Iterative size</a></span></dt> | |
| 31 | <dt><span class="section"><a href="implementation/complexity.html">Complexity</a></span></dt> | |
| 32 | <dt><span class="section"><a href="implementation/inplace_and_infix_operators.html">Inplace | |
| 33 | and infix operators</a></span></dt> | |
| 34 | </dl></div> | |
| 35 | <p> | |
| 36 | The <a class="link" href="interface.html" title="Interface">previous section</a> gave an overview | |
| 37 | over the interface of the <span class="bold"><strong>icl</strong></span> outlining <a class="link" href="interface.html#boost_icl.interface.class_templates" title="Class templates">class templates</a>, <a class="link" href="interface/associated_types.html" title="Associated Types">associated types</a> and | |
| 38 | polymorphic <a class="link" href="interface/function_synopsis.html" title="Function Synopsis">functions | |
| 39 | and operators</a>. In preparation to the <a class="link" href="function_reference.html" title="Function Reference">next | |
| 40 | section</a>, that describes the <span class="bold"><strong>icl's</strong></span> polymorphic | |
| 41 | functions in more detail together with <span class="emphasis"><em><span class="bold"><strong>complexity | |
| 42 | characteristics</strong></span></em></span>, this section summarizes some general | |
| 43 | information on implementation and performance. | |
| 44 | </p> | |
| 45 | <a name="boost_icl.implementation.stl_based_implementation"></a><h6> | |
| 46 | <a name="id1130357"></a> | |
| 47 | <a class="link" href="implementation.html#boost_icl.implementation.stl_based_implementation">STL based | |
| 48 | implementation</a> | |
| 49 | </h6> | |
| 50 | <p> | |
| 51 | The <span class="bold"><strong>implementation</strong></span> of the <span class="bold"><strong>icl's</strong></span> | |
| 52 | containers is based on <span class="bold"><strong>std::set</strong></span> and <span class="bold"><strong>std::map</strong></span>. So the underlying data structure of interval | |
| 53 | containers is a red black tree of intervals or interval value pairs. The element | |
| 54 | containers <a href="http://www.cplusplus.com/reference/stl/set/" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">set</span></code> | |
| 55 | </a> and <code class="computeroutput"><a class="link" href="../boost/icl/map.html" title="Class template map">icl::map</a></code> are wrapper | |
| 56 | classes of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">set</span></code> and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">map</span></code>. Interval | |
| 57 | containers are then using <a href="http://www.cplusplus.com/reference/stl/set/" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">sets</span></code></a> | |
| 58 | of intervals or <code class="computeroutput"><a class="link" href="../boost/icl/map.html" title="Class template map">icl::maps</a></code> of interval | |
| 59 | value pairs as implementing containers. So all the <span class="emphasis"><em><span class="bold"><strong>complexity | |
| 60 | characteristics</strong></span></em></span> of icl containers are based on and limited | |
| 61 | by the <span class="emphasis"><em><span class="bold"><strong>red-black tree implementation</strong></span></em></span> | |
| 62 | of the underlying std::AssociativeContainers. | |
| 63 | </p> | |
| 64 | <div class="section boost_icl_implementation_iterative_size" lang="en"> | |
| 65 | <div class="titlepage"><div><div><h3 class="title"> | |
| 66 | <a name="boost_icl.implementation.iterative_size"></a><a class="link" href="implementation.html#boost_icl.implementation.iterative_size" title="Iterative size">Iterative size</a> | |
| 67 | </h3></div></div></div> | |
| 68 | <p> | |
| 69 | Throughout the documentation on complexity, big <span class="emphasis"><em>O</em></span> expressions | |
| 70 | like <span class="emphasis"><em>O(n)</em></span> or <span class="emphasis"><em>O(m log n)</em></span> refer to | |
| 71 | container sizes <span class="emphasis"><em>n</em></span> and <span class="emphasis"><em>m</em></span>. In this | |
| 72 | documentation these sizes <span class="emphasis"><em><span class="bold"><strong>do not</strong></span></em></span> | |
| 73 | denote to the familiar <code class="computeroutput"><span class="identifier">size</span></code> | |
| 74 | function that returns the <span class="emphasis"><em><span class="bold"><strong>number of elements</strong></span></em></span> | |
| 75 | of a container. Because for an interval container | |
| 76 | </p> | |
| 77 | <pre class="programlisting"><span class="identifier">interval_set</span><span class="special"><</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">mono</span><span class="special">;</span> | |
| 78 | <span class="identifier">mono</span> <span class="special">+=</span> <span class="identifier">interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">closed</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">5</span><span class="special">);</span> <span class="comment">// {[1 ... 5]} | |
| 79 | </span><span class="identifier">mono</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">5</span><span class="special">;</span> <span class="comment">// true, 5 elements | |
| 80 | </span><span class="identifier">mono</span><span class="special">.</span><span class="identifier">interval_count</span><span class="special">()</span> <span class="special">==</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// true, only one interval | |
| 81 | </span></pre> | |
| 82 | <p> | |
| 83 | </p> | |
| 84 | <p> | |
| 85 | it's size and the number of contained intervals is usually different. To | |
| 86 | refer uniformly to a <span class="emphasis"><em>size</em></span> that matters for iteration, | |
| 87 | which is the decisive kind of size concerning algorithmic behavior there | |
| 88 | is a function | |
| 89 | </p> | |
| 90 | <pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">T</span><span class="special">::</span><span class="identifier">iterative_size</span><span class="special">()</span><span class="keyword">const</span><span class="special">;</span> <span class="comment">// Number of entities that can be iterated over. | |
| 91 | </span></pre> | |
| 92 | <p> | |
| 93 | for all element and interval containers of the icl. So for complexity statements | |
| 94 | throughout the icl's documentation the sizes will be <code class="computeroutput"><span class="identifier">iterative_sizes</span></code> | |
| 95 | and big <span class="emphasis"><em>O</em></span> expressions like <span class="emphasis"><em>O(m log n)</em></span> | |
| 96 | will refer to sizes | |
| 97 | </p> | |
| 98 | <pre class="programlisting"><span class="identifier">n</span> <span class="special">=</span> <span class="identifier">y</span><span class="special">.</span><span class="identifier">iterative_size</span><span class="special">();</span> | |
| 99 | <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">x</span><span class="special">.</span><span class="identifier">iterative_size</span><span class="special">();</span> | |
| 100 | </pre> | |
| 101 | <p> | |
| 102 | for containers <code class="computeroutput"><span class="identifier">y</span></code> and <code class="computeroutput"><span class="identifier">x</span></code>. Note that | |
| 103 | </p> | |
| 104 | <pre class="programlisting"><span class="identifier">iterative_size</span></pre> | |
| 105 | <p> | |
| 106 | refers to the primary entities, that we can iterate over. For interval containers | |
| 107 | these are intervals or segments. | |
| 108 | </p> | |
| 109 | <pre class="programlisting"><span class="identifier">Itervative_size</span></pre> | |
| 110 | <p> | |
| 111 | never refers to element iteration for interval containers. | |
| 112 | </p> | |
| 113 | </div> | |
| 114 | </div> | |
| 115 | <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> | |
| 116 | <td align="left"></td> | |
| 117 | <td align="right"><div class="copyright-footer">Copyright © 2007 -2010 Joachim Faulhaber<br>Copyright © 1999 -2006 Cortex Software GmbH<p> | |
| 118 | Distributed under the Boost Software License, Version 1.0. (See accompanying | |
| 119 | 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>) | |
| 120 | </p> | |
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