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<div class="refnamediv">
<h1 class="refname">bcpow</h1>
<p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">bcpow</span> — <span class="dc-title">Raise an arbitrary precision number to another</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.bcpow-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">string</span> <span class="methodname"><strong>bcpow</strong></span>
( <span class="methodparam"><span class="type">string</span> <code class="parameter">$base</code></span>
, <span class="methodparam"><span class="type">string</span> <code class="parameter">$exponent</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$scale</code><span class="initializer"> = 0</span></span>
] )</div>
<p class="para rdfs-comment">
Raise <code class="parameter">base</code> to the power
<code class="parameter">exponent</code>.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.bcpow-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">base</code></dt>
<dd>
<p class="para">
The base, as a string.
</p>
</dd>
<dt>
<code class="parameter">exponent</code></dt>
<dd>
<p class="para">
The exponent, as a string. If the exponent is non-integral, it is truncated.
The valid range of the exponent is platform specific, but is at least
<em>-2147483648</em> to <em>2147483647</em>.
</p>
</dd>
<dt>
<code class="parameter">
scale</code></dt>
<dd>
<p class="para">This optional parameter is used to set the number
of digits after the decimal place in the result. If omitted, it will default to the scale set
globally with the <span class="function"><a href="function.bcscale.html" class="function">bcscale()</a></span> function, or fallback to <em>0</em> if
this has not been set.</p></dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.bcpow-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns the result as a string.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.bcpow-changelog">
<h3 class="title">Changelog</h3>
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>7.3.0</td>
<td>
<span class="function"><strong>bcpow()</strong></span> now returns numbers with the requested scale.
Formerly, the returned numbers may have omitted trailing decimal zeroes.
</td>
</tr>
</tbody>
</table>
</div>
<div class="refsect1 examples" id="refsect1-function.bcpow-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-4184">
<p><strong>Example #1 <span class="function"><strong>bcpow()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">bcpow</span><span style="color: #007700">(</span><span style="color: #DD0000">'4.2'</span><span style="color: #007700">, </span><span style="color: #DD0000">'3'</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">); </span><span style="color: #FF8000">// 74.08<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</div>
<div class="refsect1 notes" id="refsect1-function.bcpow-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
Before PHP 7.3.0 <span class="function"><strong>bcpow()</strong></span> may return a result with fewer digits after the
decimal point than the <code class="parameter">scale</code> parameter would
indicate. This only occurs when the result doesn't require all of the
precision allowed by the <code class="parameter">scale</code>. For example:
<div class="example" id="example-4185">
<p><strong>Example #2 <span class="function"><strong>bcpow()</strong></span> scale example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">bcpow</span><span style="color: #007700">(</span><span style="color: #DD0000">'5'</span><span style="color: #007700">, </span><span style="color: #DD0000">'2'</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">); </span><span style="color: #FF8000">// prints "25", not "25.00"<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.bcpow-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"><span class="function"><a href="function.bcpowmod.html" class="function" rel="rdfs-seeAlso">bcpowmod()</a> - Raise an arbitrary precision number to another, reduced by a specified modulus</span></li>
<li class="member"><span class="function"><a href="function.bcsqrt.html" class="function" rel="rdfs-seeAlso">bcsqrt()</a> - Get the square root of an arbitrary precision number</span></li>
</ul>
</p>
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