mirror of
https://github.com/fofolee/uTools-Manuals.git
synced 2025-06-29 21:12:42 +08:00
107 lines
4.7 KiB
HTML
107 lines
4.7 KiB
HTML
<!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>Check if number is "probably prime"</title>
|
|
</head>
|
|
<body class="docs"><div id="layout">
|
|
<div id="layout-content"><div id="function.gmp-prob-prime" class="refentry">
|
|
<div class="refnamediv">
|
|
<h1 class="refname">gmp_prob_prime</h1>
|
|
<p class="verinfo">(PHP 4 >= 4.0.4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">gmp_prob_prime</span> — <span class="dc-title">Check if number is "probably prime"</span></p>
|
|
|
|
</div>
|
|
|
|
<div class="refsect1 description" id="refsect1-function.gmp-prob-prime-description">
|
|
<h3 class="title">说明</h3>
|
|
<div class="methodsynopsis dc-description">
|
|
<span class="methodname"><strong>gmp_prob_prime</strong></span>
|
|
( <span class="methodparam"><span class="type"><a href="class.gmp.html" class="type GMP">GMP</a></span> <code class="parameter">$a</code></span>
|
|
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$reps</code><span class="initializer"> = 10</span></span>
|
|
] ) : <span class="type">int</span></div>
|
|
|
|
<p class="para rdfs-comment">
|
|
The function uses Miller-Rabin's probabilistic test to check if a number is a prime.
|
|
</p>
|
|
</div>
|
|
|
|
|
|
<div class="refsect1 parameters" id="refsect1-function.gmp-prob-prime-parameters">
|
|
<h3 class="title">参数</h3>
|
|
<p class="para">
|
|
<dl>
|
|
|
|
|
|
<dt>
|
|
<code class="parameter">a</code></dt>
|
|
|
|
<dd>
|
|
|
|
<p class="para">
|
|
The number being checked as a prime.
|
|
</p>
|
|
<p class="para">可以是一个 GMP
|
|
数据 <span class="type"><span class="type resouce">resouce</span></span>，或一个可以转换为数值的字符串。</p>
|
|
</dd>
|
|
|
|
|
|
|
|
<dt>
|
|
<code class="parameter">reps</code></dt>
|
|
|
|
<dd>
|
|
|
|
<p class="para">
|
|
Reasonable values
|
|
of <code class="parameter">reps</code> vary from 5 to 10 (default being
|
|
10); a higher value lowers the probability for a non-prime to
|
|
pass as a "probable" prime.
|
|
</p>
|
|
<p class="para">可以是一个 GMP
|
|
数据 <span class="type"><span class="type resouce">resouce</span></span>，或一个可以转换为数值的字符串。</p>
|
|
</dd>
|
|
|
|
|
|
</dl>
|
|
|
|
</p>
|
|
</div>
|
|
|
|
|
|
<div class="refsect1 returnvalues" id="refsect1-function.gmp-prob-prime-returnvalues">
|
|
<h3 class="title">返回值</h3>
|
|
<p class="para">
|
|
If this function returns 0, <code class="parameter">a</code> is
|
|
definitely not prime. If it returns 1, then
|
|
<code class="parameter">a</code> is "probably" prime. If it returns 2,
|
|
then <code class="parameter">a</code> is surely prime.
|
|
</p>
|
|
</div>
|
|
|
|
|
|
<div class="refsect1 examples" id="refsect1-function.gmp-prob-prime-examples">
|
|
<h3 class="title">范例</h3>
|
|
<p class="para">
|
|
<div class="example" id="example-4092">
|
|
<p><strong>Example #1 <span class="function"><strong>gmp_prob_prime()</strong></span> example</strong></p>
|
|
<div class="example-contents">
|
|
<div class="phpcode"><pre><span style="color: #000000">
|
|
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// definitely not a prime<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">gmp_prob_prime</span><span style="color: #007700">(</span><span style="color: #DD0000">"6"</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// probably a prime<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">gmp_prob_prime</span><span style="color: #007700">(</span><span style="color: #DD0000">"1111111111111111111"</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// definitely a prime<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">gmp_prob_prime</span><span style="color: #007700">(</span><span style="color: #DD0000">"11"</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?></span>
|
|
</span>
|
|
</pre></div>
|
|
</div>
|
|
|
|
<div class="example-contents"><p>以上例程会输出：</p></div>
|
|
<div class="example-contents screen">
|
|
<div class="cdata"><pre>
|
|
0
|
|
1
|
|
2
|
|
</pre></div>
|
|
</div>
|
|
</div>
|
|
</p>
|
|
</div>
|
|
|
|
|
|
</div></div></div></body></html> |