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| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="spirit.qi.reference.numeric"></a><a class="link" href="numeric.html" title="Numeric">Numeric</a> |
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| <div class="toc"><dl> |
| <dt><span class="section"><a href="numeric/uint.html">Unsigned Integers |
| (<code class="computeroutput"><span class="identifier">uint_</span></code>, etc.)</a></span></dt> |
| <dt><span class="section"><a href="numeric/int.html">Signed Integers |
| (<code class="computeroutput"><span class="identifier">int_</span></code>, etc.)</a></span></dt> |
| <dt><span class="section"><a href="numeric/real.html">Real Numbers (<code class="computeroutput"><span class="identifier">float_</span></code>, <code class="computeroutput"><span class="identifier">double_</span></code>, |
| etc.)</a></span></dt> |
| <dt><span class="section"><a href="numeric/boolean.html">Boolean Parser |
| (<code class="computeroutput"><span class="identifier">bool_</span></code>)</a></span></dt> |
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| <p> |
| The library includes a couple of predefined objects for parsing signed |
| and unsigned integers and real numbers. These parsers are fully parametric. |
| Most of the important aspects of numeric parsing can be finely adjusted |
| to suit. This includes the radix base, the minimum and maximum number of |
| allowable digits, the exponent, the fraction etc. Policies control the |
| real number parsers' behavior. There are some predefined policies covering |
| the most common real number formats but the user can supply her own when |
| needed. |
| </p> |
| <p> |
| The numeric parsers are fine tuned (employing loop unrolling and extensive |
| template metaprogramming) with exceptional performance that rivals the |
| low level C functions such as <code class="computeroutput"><span class="identifier">atof</span></code>, |
| <code class="computeroutput"><span class="identifier">strtod</span></code>, <code class="computeroutput"><span class="identifier">atol</span></code>, |
| <code class="computeroutput"><span class="identifier">strtol</span></code>. Benchmarks reveal |
| up to 4X speed over the C counterparts. This goes to show that you can |
| write extremely tight generic C++ code that rivals, if not surpasses C. |
| </p> |
| <a name="spirit.qi.reference.numeric.module_header"></a><h6> |
| <a name="id903159"></a> |
| <a class="link" href="numeric.html#spirit.qi.reference.numeric.module_header">Module Header</a> |
| </h6> |
| <pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/qi/numeric.hpp> |
| </span><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_numeric</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| </pre> |
| <p> |
| Also, see <a class="link" href="../../structure/include.html" title="Include">Include Structure</a>. |
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| <td align="right"><div class="copyright-footer">Copyright © 2001-2010 Joel de Guzman, Hartmut Kaiser<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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