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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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<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.
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<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.
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<a name="spirit.qi.reference.numeric.module_header"></a><h6>
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<a class="link" href="numeric.html#spirit.qi.reference.numeric.module_header">Module Header</a>
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<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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