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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="algorithm.Misc"></a><a class="link" href="Misc.html" title="Other Algorithms">Other Algorithms</a>
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<div class="toc"><dl>
<dt><span class="section"><a href="Misc.html#the_boost_algorithm_library.Misc.clamp">clamp</a></span></dt>
<dt><span class="section"><a href="../the_boost_algorithm_library/Misc/hex.html">hex</a></span></dt>
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<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="the_boost_algorithm_library.Misc.clamp"></a><a class="link" href="Misc.html#the_boost_algorithm_library.Misc.clamp" title="clamp">clamp</a>
</h3></div></div></div>
<p>
The header file clamp.hpp contains two functions for "clamping"
a value between a pair of boundary values.
</p>
<h5>
<a name="the_boost_algorithm_library.Misc.clamp.h0"></a>
<span><a name="the_boost_algorithm_library.Misc.clamp.clamp"></a></span><a class="link" href="Misc.html#the_boost_algorithm_library.Misc.clamp.clamp">clamp</a>
</h5>
<p>
The function <code class="computeroutput"><span class="identifier">clamp</span> <span class="special">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">lo</span><span class="special">,</span> <span class="identifier">hi</span><span class="special">)</span></code>
returns:
</p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
lo if v < lo
</li>
<li class="listitem">
hi if hi < v
</li>
<li class="listitem">
otherwise, v
</li>
</ul></div>
<p>
Note: using <code class="computeroutput"><span class="identifier">clamp</span></code> with floating
point numbers may give unexpected results if one of the values is <code class="computeroutput"><span class="identifier">NaN</span></code>.
</p>
<p>
There is also a version that allows the caller to specify a comparison predicate
to use instead of <code class="computeroutput"><span class="keyword">operator</span> <span class="special"><</span></code>.
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">V</span><span class="special">></span>
<span class="identifier">V</span> <span class="identifier">clamp</span> <span class="special">(</span> <span class="identifier">V</span> <span class="identifier">val</span><span class="special">,</span> <span class="identifier">V</span> <span class="identifier">lo</span><span class="special">,</span> <span class="identifier">V</span> <span class="identifier">hi</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">V</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Pred</span><span class="special">></span>
<span class="identifier">V</span> <span class="identifier">clamp</span> <span class="special">(</span> <span class="identifier">V</span> <span class="identifier">val</span><span class="special">,</span> <span class="identifier">V</span> <span class="identifier">lo</span><span class="special">,</span> <span class="identifier">V</span> <span class="identifier">hi</span><span class="special">,</span> <span class="identifier">Pred</span> <span class="identifier">p</span> <span class="special">);</span>
</pre>
<p>
</p>
<p>
The following code:
</p>
<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">foo</span> <span class="special">=</span> <span class="number">23</span><span class="special">;</span>
<span class="identifier">foo</span> <span class="special">=</span> <span class="identifier">clamp</span> <span class="special">(</span> <span class="identifier">foo</span><span class="special">,</span> <span class="number">1</span><span class="special">,</span> <span class="number">10</span> <span class="special">);</span>
</pre>
<p>
will leave <code class="computeroutput"><span class="identifier">foo</span></code> with a value
of 10
</p>
<p>
Complexity: <code class="computeroutput"><span class="identifier">clamp</span></code> will make
either one or two calls to the comparison predicate before returning one
of the three parameters.
</p>
<h5>
<a name="the_boost_algorithm_library.Misc.clamp.h1"></a>
<span><a name="the_boost_algorithm_library.Misc.clamp.clamp_range"></a></span><a class="link" href="Misc.html#the_boost_algorithm_library.Misc.clamp.clamp_range">clamp_range</a>
</h5>
<p>
There are also four range-based versions of clamp, that apply clamping to
a series of values. You could write them yourself with std::transform and
bind, like this: <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">transform</span> <span class="special">(</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">last</span><span class="special">,</span> <span class="identifier">out</span><span class="special">,</span> <span class="identifier">bind</span>
<span class="special">(</span> <span class="identifier">clamp</span>
<span class="special">(</span> <span class="identifier">_1</span><span class="special">,</span> <span class="identifier">lo</span><span class="special">,</span>
<span class="identifier">hi</span> <span class="special">)))</span></code>,
but they are provided here for your convenience.
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">OutputIterator</span><span class="special">></span>
<span class="identifier">OutputIterator</span> <span class="identifier">clamp_range</span> <span class="special">(</span> <span class="identifier">InputIterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">InputIterator</span> <span class="identifier">last</span><span class="special">,</span> <span class="identifier">OutputIterator</span> <span class="identifier">out</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="identifier">InputIterator</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">lo</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="identifier">InputIterator</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">hi</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Range</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">OutputIterator</span><span class="special">></span>
<span class="identifier">OutputIterator</span> <span class="identifier">clamp_range</span> <span class="special">(</span> <span class="keyword">const</span> <span class="identifier">Range</span> <span class="special">&</span><span class="identifier">r</span><span class="special">,</span> <span class="identifier">OutputIterator</span> <span class="identifier">out</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">lo</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">hi</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">OutputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Pred</span><span class="special">></span>
<span class="identifier">OutputIterator</span> <span class="identifier">clamp_range</span> <span class="special">(</span> <span class="identifier">InputIterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">InputIterator</span> <span class="identifier">last</span><span class="special">,</span> <span class="identifier">OutputIterator</span> <span class="identifier">out</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="identifier">InputIterator</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">lo</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="identifier">InputIterator</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">hi</span><span class="special">,</span> <span class="identifier">Pred</span> <span class="identifier">p</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Range</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">OutputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Pred</span><span class="special">></span>
<span class="identifier">OutputIterator</span> <span class="identifier">clamp_range</span> <span class="special">(</span> <span class="keyword">const</span> <span class="identifier">Range</span> <span class="special">&</span><span class="identifier">r</span><span class="special">,</span> <span class="identifier">OutputIterator</span> <span class="identifier">out</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">lo</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">value_type</span> <span class="identifier">hi</span><span class="special">,</span>
<span class="identifier">Pred</span> <span class="identifier">p</span> <span class="special">);</span>
</pre>
<p>
</p>
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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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