mirror of
https://github.com/sigmasternchen/php-doc-en
synced 2025-03-20 19:08:54 +00:00
0172434e4d
git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@132013 c90b9560-bf6c-de11-be94-00142212c4b1
59 lines
1.8 KiB
XML
59 lines
1.8 KiB
XML
<?xml version="1.0" encoding="iso-8859-1"?>
|
|
<!-- $Revision: 1.8 $ -->
|
|
<!-- splitted from ./en/functions/math.xml, last change in rev 1.2 -->
|
|
<refentry id="function.log">
|
|
<refnamediv>
|
|
<refname>log</refname>
|
|
<refpurpose>Natural logarithm</refpurpose>
|
|
</refnamediv>
|
|
<refsect1>
|
|
<title>Description</title>
|
|
<methodsynopsis>
|
|
<type>float</type><methodname>log</methodname>
|
|
<methodparam><type>float</type><parameter>arg</parameter></methodparam>
|
|
<methodparam choice="opt"><type>float</type><parameter>base</parameter></methodparam>
|
|
</methodsynopsis>
|
|
<para>
|
|
If the optional <parameter>base</parameter> parameter is specified,
|
|
<function>log</function> returns log<subscript>base</subscript>
|
|
<parameter>arg</parameter>, otherwise <function>log</function>
|
|
returns the natural logarithm of <parameter>arg</parameter>.
|
|
</para>
|
|
<note>
|
|
<para>
|
|
The <parameter>base</parameter> parameter became available
|
|
with PHP version 4.3.0.
|
|
</para>
|
|
<para>
|
|
As always you can calculate the logarithm in base <literal>b</literal>
|
|
of a number <literal>n</literal>, but using the mathematical identity:
|
|
log<subscript>b</subscript>(n) = log(n)/log(b), where log is the
|
|
neperian (or natural) logarithm.
|
|
</para>
|
|
</note>
|
|
<para>
|
|
See also <function>exp</function>.
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|
|
|
|
<!-- Keep this comment at the end of the file
|
|
Local variables:
|
|
mode: sgml
|
|
sgml-omittag:t
|
|
sgml-shorttag:t
|
|
sgml-minimize-attributes:nil
|
|
sgml-always-quote-attributes:t
|
|
sgml-indent-step:1
|
|
sgml-indent-data:t
|
|
indent-tabs-mode:nil
|
|
sgml-parent-document:nil
|
|
sgml-default-dtd-file:"../../../../manual.ced"
|
|
sgml-exposed-tags:nil
|
|
sgml-local-catalogs:nil
|
|
sgml-local-ecat-files:nil
|
|
End:
|
|
vim600: syn=xml fen fdm=syntax fdl=2 si
|
|
vim: et tw=78 syn=sgml
|
|
vi: ts=1 sw=1
|
|
-->
|