<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Scan for 1</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.gmp-scan0.html">gmp_scan0</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.gmp-setbit.html">gmp_setbit</a></div> <div class="up"><a href="ref.gmp.html">GMP Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="function.gmp-scan1" class="refentry"> <div class="refnamediv"> <h1 class="refname">gmp_scan1</h1> <p class="verinfo">(PHP 4 >= 4.0.4, PHP 5)</p><p class="refpurpose"><span class="refname">gmp_scan1</span> — <span class="dc-title">Scan for 1</span></p> </div> <div class="refsect1 description" id="refsect1-function.gmp-scan1-description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">int</span> <span class="methodname"><strong>gmp_scan1</strong></span> ( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$a</code></span> , <span class="methodparam"><span class="type">int</span> <code class="parameter">$start</code></span> )</div> <p class="para rdfs-comment"> Scans <em><code class="parameter">a</code></em>, starting with bit <em><code class="parameter">start</code></em>, towards more significant bits, until the first set bit is found. </p> </div> <div class="refsect1 parameters" id="refsect1-function.gmp-scan1-parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><em><code class="parameter">a</code></em></span> <dd> <p class="para"> The number to scan. </p> <p class="para">It can be either a GMP number <span class="type"><a href="language.types.resource.html" class="type resource">resource</a></span>, or a numeric string given that it is possible to convert the latter to a number.</p> </dd> </dt> <dt> <span class="term"><em><code class="parameter">start</code></em></span> <dd> <p class="para"> The starting bit. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues" id="refsect1-function.gmp-scan1-returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns the index of the found bit, as an <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span>. If no set bit is found, -1 is returned. </p> </div> <div class="refsect1 examples" id="refsect1-function.gmp-scan1-examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example" id="example-3430"> <p><strong>Example #1 <span class="function"><strong>gmp_scan1()</strong></span> 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: #FF8000">// "1" bit is found at position 3. index starts at 0<br /></span><span style="color: #0000BB">$s1 </span><span style="color: #007700">= </span><span style="color: #0000BB">gmp_init</span><span style="color: #007700">(</span><span style="color: #DD0000">"01000"</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">gmp_scan1</span><span style="color: #007700">(</span><span style="color: #0000BB">$s1</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// "1" bit is found at position 9. index starts at 5<br /></span><span style="color: #0000BB">$s2 </span><span style="color: #007700">= </span><span style="color: #0000BB">gmp_init</span><span style="color: #007700">(</span><span style="color: #DD0000">"01000001111"</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">gmp_scan1</span><span style="color: #007700">(</span><span style="color: #0000BB">$s2</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?></span> </span> </code></div> </div> <div class="example-contents"><p>The above example will output:</p></div> <div class="example-contents screen"> <div class="cdata"><pre> 3 9 </pre></div> </div> </div> </p> </div> </div><hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.gmp-scan0.html">gmp_scan0</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.gmp-setbit.html">gmp_setbit</a></div> <div class="up"><a href="ref.gmp.html">GMP Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>