ceph/src/boost/libs/math/doc/html/math_toolkit/rounding/trunc.html

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  27 <a name="math_toolkit.rounding.trunc"></a><a class="link" href="trunc.html" title="Truncation Functions">Truncation Functions</a>
  28 </h3></div></div></div>
  29 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">math</span><span class="special">/</span><span class="identifier">special_functions</span><span class="special">/</span><span class="identifier">trunc</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></pre>
  30 <pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
  31 <span class="identifier">T</span> <span class="identifier">trunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">);</span>
  32
  33 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Policy</span><span class="special">&gt;</span>
  34 <span class="identifier">T</span> <span class="identifier">trunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Policy</span><span class="special">&amp;);</span>
  35
  36 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
  37 <span class="keyword">int</span> <span class="identifier">itrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">);</span>
  38
  39 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Policy</span><span class="special">&gt;</span>
  40 <span class="keyword">int</span> <span class="identifier">itrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Policy</span><span class="special">&amp;);</span>
  41
  42 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
  43 <span class="keyword">long</span> <span class="identifier">ltrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">);</span>
  44
  45 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Policy</span><span class="special">&gt;</span>
  46 <span class="keyword">long</span> <span class="identifier">ltrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Policy</span><span class="special">&amp;);</span>
  47
  48 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
  49 <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">lltrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">);</span>
  50
  51 <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Policy</span><span class="special">&gt;</span>
  52 <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">lltrunc</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Policy</span><span class="special">&amp;);</span>
  53 </pre>
  54 <p>
  55         The trunc functions round their argument to the integer value, nearest to
  56         but no larger in magnitude than the argument.
  57       </p>
  58 <p>
  59         For example <code class="computeroutput"><span class="identifier">itrunc</span><span class="special">(</span><span class="number">3.7</span><span class="special">)</span></code> would
  60         return <code class="computeroutput"><span class="number">3</span></code> and <code class="computeroutput"><span class="identifier">ltrunc</span><span class="special">(-</span><span class="number">4.6</span><span class="special">)</span></code>
  61         would return <code class="computeroutput"><span class="special">-</span><span class="number">4</span></code>.
  62       </p>
  63 <p>
  64         If the argument <span class="emphasis"><em>v</em></span> is either non-finite or else outside
  65         the range of the result type, then returns the result of <a class="link" href="../error_handling.html#math_toolkit.error_handling.rounding_error">rounding_error</a>:
  66         by default this throws an instance of <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">math</span><span class="special">::</span><span class="identifier">rounding_error</span></code>.
  67       </p>
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  71 <td align="right"><div class="copyright-footer">Copyright &#169; 2006-2010, 2012-2014 Nikhar Agrawal,
  72       Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos, Hubert
  73       Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Johan R&#229;de, Gautam Sewani,
  74       Benjamin Sobotta, Thijs van den Berg, Daryle Walker and Xiaogang Zhang<p>
  75         Distributed under the Boost Software License, Version 1.0. (See accompanying
  76         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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