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| <div class="section"> |
| <div class="titlepage"><div><div><h5 class="title"> |
| <a name="fusion.algorithm.query.functions.count"></a><a class="link" href="count.html" title="count">count</a> |
| </h5></div></div></div> |
| <a name="fusion.algorithm.query.functions.count.description"></a><h6> |
| <a name="id971882"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.description">Description</a> |
| </h6> |
| <p> |
| Returns the number of elements of a given type within a sequence. |
| </p> |
| <a name="fusion.algorithm.query.functions.count.synopsis"></a><h6> |
| <a name="id971898"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.synopsis">Synopsis</a> |
| </h6> |
| <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> |
| <span class="keyword">typename</span> <span class="identifier">Sequence</span><span class="special">,</span> |
| <span class="keyword">typename</span> <span class="identifier">T</span> |
| <span class="special">></span> |
| <span class="keyword">typename</span> <a class="link" href="../metafunctions/count.html" title="count"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">count</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">,</span> <span class="identifier">T</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">count</span><span class="special">(</span> |
| <span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">t</span><span class="special">);</span> |
| </pre> |
| <div class="table"> |
| <a name="id972044"></a><p class="title"><b>Table 1.54. Parameters</b></p> |
| <div class="table-contents"><table class="table" summary="Parameters"> |
| <colgroup> |
| <col> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Parameter |
| </p> |
| </th> |
| <th> |
| <p> |
| Requirement |
| </p> |
| </th> |
| <th> |
| <p> |
| Description |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">seq</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| A model of <a class="link" href="../../../sequence/concepts/forward_sequence.html" title="Forward Sequence">Forward |
| Sequence</a>, <code class="computeroutput"><span class="identifier">e</span> |
| <span class="special">==</span> <span class="identifier">t</span></code> |
| must be a valid expression, convertible to <code class="computeroutput"><span class="keyword">bool</span></code>, |
| for each element <code class="computeroutput"><span class="identifier">e</span></code> |
| in <code class="computeroutput"><span class="identifier">seq</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The sequence to search |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">T</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Any type |
| </p> |
| </td> |
| <td> |
| <p> |
| The type to count |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <br class="table-break"><a name="fusion.algorithm.query.functions.count.expression_semantics"></a><h6> |
| <a name="id972204"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.expression_semantics">Expression |
| Semantics</a> |
| </h6> |
| <pre class="programlisting"><a class="link" href="count.html" title="count"><code class="computeroutput"><span class="identifier">count</span></code></a><span class="special">(</span><span class="identifier">seq</span><span class="special">,</span> <span class="identifier">t</span><span class="special">);</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Return type</strong></span>: <code class="computeroutput"><span class="keyword">int</span></code> |
| </p> |
| <p> |
| <span class="bold"><strong>Semantics</strong></span>: Returns the number of elements |
| of type <code class="computeroutput"><span class="identifier">T</span></code> and equal to |
| <code class="computeroutput"><span class="identifier">t</span></code> in <code class="computeroutput"><span class="identifier">seq</span></code>. |
| </p> |
| <a name="fusion.algorithm.query.functions.count.complexity"></a><h6> |
| <a name="id972298"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.complexity">Complexity</a> |
| </h6> |
| <p> |
| Linear. At most <code class="computeroutput"><a class="link" href="../../../sequence/intrinsic/metafunctions/size.html" title="size"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">size</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">>::</span><span class="identifier">value</span></code> comparisons. |
| </p> |
| <a name="fusion.algorithm.query.functions.count.header"></a><h6> |
| <a name="id972348"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.header">Header</a> |
| </h6> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">/</span><span class="identifier">query</span><span class="special">/</span><span class="identifier">count</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">count</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| </pre> |
| <a name="fusion.algorithm.query.functions.count.example"></a><h6> |
| <a name="id972464"></a> |
| <a class="link" href="count.html#fusion.algorithm.query.functions.count.example">Example</a> |
| </h6> |
| <pre class="programlisting"><span class="keyword">const</span> <a class="link" href="../../../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a><span class="special"><</span><span class="keyword">double</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">vec</span><span class="special">(</span><span class="number">1.0</span><span class="special">,</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">);</span> |
| <span class="identifier">assert</span><span class="special">(</span><a class="link" href="count.html" title="count"><code class="computeroutput"><span class="identifier">count</span></code></a><span class="special">(</span><span class="identifier">vec</span><span class="special">,</span><span class="number">2</span><span class="special">)</span> <span class="special">==</span> <span class="number">1</span><span class="special">);</span> |
| </pre> |
| </div> |
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| <td align="right"><div class="copyright-footer">Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias |
| Schwinger<p> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 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>) |
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