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<h1 class="title">Introduction</h1>
<p class="simpara">
These functions allow for arbitrary-length integers to be worked with using
the GNU <acronym title="Multiple Precision">MP</acronym> library.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
Most GMP functions accept GMP number arguments. These are shown in this
documentation as <a href="class.gmp.html" class="classname">GMP</a> objects. However, note that PHP
5.5 and earlier represented GMP numbers as <span class="type"><a href="language.types.resource.html" class="type resource">resource</a></span>s. Most
of these functions will also accept numeric and string arguments, so long
as it is possible to convert the latter to a number. Also, if there is a
more performant function that can operate on the arguments (integers only),
then it will be used instead (this is done transparently). See also the
<span class="function"><a href="function.gmp-init.html" class="function">gmp_init()</a></span> function.
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
From PHP 5.6 onwards, the
<a href="language.operators.arithmetic.html" class="link">arithmetic</a>,
<a href="language.operators.bitwise.html" class="link">bitwise</a>, and
<a href="language.operators.comparison.html" class="link">comparison</a> operators
may be used with the <a href="class.gmp.html" class="classname">GMP</a> objects returned from
<span class="function"><a href="function.gmp-init.html" class="function">gmp_init()</a></span> and other GMP functions.
</p>
</p></blockquote>
<div class="warning"><strong class="warning">Warning</strong>
<p class="simpara">
Large integers must be specified as strings - otherwise, PHP will coerce
them to floats, resulting in a loss of precision.
</p>
</div>
<blockquote class="note"><p><strong class="note">Note</strong>:
<span class="simpara">
This extension is available on Windows platforms since PHP 5.1.0.
</span>
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