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https://github.com/sigmasternchen/php-doc-en
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git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@152424 c90b9560-bf6c-de11-be94-00142212c4b1
77 lines
2.1 KiB
XML
77 lines
2.1 KiB
XML
<?xml version="1.0" encoding="iso-8859-1"?>
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<!-- $Revision: 1.4 $ -->
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<!-- splitted from ./en/functions/gmp.xml, last change in rev 1.1 -->
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<refentry id="function.gmp-prob-prime">
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<refnamediv>
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<refname>gmp_prob_prime</refname>
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<refpurpose>Check if number is "probably prime"</refpurpose>
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</refnamediv>
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<refsect1>
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<title>Description</title>
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<methodsynopsis>
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<type>int</type><methodname>gmp_prob_prime</methodname>
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<methodparam><type>resource</type><parameter>a</parameter></methodparam>
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<methodparam choice="opt"><type>int</type><parameter>reps</parameter></methodparam>
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</methodsynopsis>
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<para>
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If this function returns 0, <parameter>a</parameter> is
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definitely not prime. If it returns 1, then
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<parameter>a</parameter> is "probably" prime. If it returns 2,
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then <parameter>a</parameter> is surely prime. Reasonable values
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of <parameter>reps</parameter> vary from 5 to 10 (default being
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10); a higher value lowers the probability for a non-prime to
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pass as a "probable" prime.
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</para>
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<para>
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The function uses Miller-Rabin's probabilistic test.
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</para>
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<example>
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<title><function>gmp_prob_prime</function> example</title>
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<programlisting role="php">
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<![CDATA[
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<?php
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// definitely not a prime
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echo gmp_prob_prime("6") . "\n";
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// probably a prime
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echo gmp_prob_prime("1111111111111111111") . "\n";
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// definitely a prime
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echo gmp_prob_prime("11") . "\n";
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?>
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]]>
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</programlisting>
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<para>
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The printout of the above program will be:
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</para>
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<screen>
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<![CDATA[
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0
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1
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2
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]]>
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</screen>
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</example>
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</refsect1>
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</refentry>
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<!-- Keep this comment at the end of the file
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Local variables:
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mode: sgml
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sgml-omittag:t
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sgml-shorttag:t
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sgml-minimize-attributes:nil
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sgml-always-quote-attributes:t
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sgml-indent-step:1
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sgml-indent-data:t
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indent-tabs-mode:nil
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sgml-parent-document:nil
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sgml-default-dtd-file:"../../../../manual.ced"
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sgml-exposed-tags:nil
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sgml-local-catalogs:nil
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sgml-local-ecat-files:nil
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End:
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vim600: syn=xml fen fdm=syntax fdl=2 si
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vim: et tw=78 syn=sgml
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vi: ts=1 sw=1
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-->
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