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<title>Finding the Next Smaller Representable Value (float_prior)</title>
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<div class="titlepage"><div><div><h3 class="title">
<a name="math_toolkit.next_float.float_prior"></a><a class="link" href="float_prior.html" title="Finding the Next Smaller Representable Value (float_prior)">Finding the Next
Smaller Representable Value (float_prior)</a>
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<h5>
<a name="math_toolkit.next_float.float_prior.h0"></a>
<span class="phrase"><a name="math_toolkit.next_float.float_prior.synopsis"></a></span><a class="link" href="float_prior.html#math_toolkit.next_float.float_prior.synopsis">Synopsis</a>
</h5>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</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">next</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
</pre>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">math</span><span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">FPT</span><span class="special">></span>
<span class="identifier">FPT</span> <span class="identifier">float_prior</span><span class="special">(</span><span class="identifier">FPT</span> <span class="identifier">val</span><span class="special">);</span>
<span class="special">}}</span> <span class="comment">// namespaces</span>
</pre>
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<a name="math_toolkit.next_float.float_prior.h1"></a>
<span class="phrase"><a name="math_toolkit.next_float.float_prior.description_float_prior"></a></span><a class="link" href="float_prior.html#math_toolkit.next_float.float_prior.description_float_prior">Description
- float_prior</a>
</h5>
<p>
Returns the next representable value which is less than <span class="emphasis"><em>x</em></span>.
If <span class="emphasis"><em>x</em></span> is non-finite then returns the result of a <a class="link" href="../error_handling.html#math_toolkit.error_handling.domain_error">domain_error</a>. If
there is no such value less than <span class="emphasis"><em>x</em></span> then returns an
<a class="link" href="../error_handling.html#math_toolkit.error_handling.overflow_error">overflow_error</a>.
</p>
<p>
Has the same effect as
</p>
<pre class="programlisting"><span class="identifier">nextafter</span><span class="special">(</span><span class="identifier">val</span><span class="special">,</span> <span class="special">-(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">numeric_limits</span><span class="special"><</span><span class="identifier">FPT</span><span class="special">>::</span><span class="identifier">max</span><span class="special">)());</span> <span class="comment">// Note most negative value -max.</span>
</pre>
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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