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PHP log () function

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Examples

Returns the natural logarithm different numbers:

<?php
echo(log(2.7183) . "<br>");
echo(log(2) . "<br>");
echo(log(1) . "<br>");
echo(log(0);
?>

Running instance »

Definition and Usage

log () function returns the number of the natural logarithm of a number, or a number to the base for the bottom of.


grammar

log( number,base );

参数 描述
number 必需。规定需计算对数的值。
base 可选。要使用的对数的底。默认是 'e'。

technical details

return value: Logarithm natural logarithm of a number, or a number to the base for the bottom of.
Return type: Float
PHP version: 4+
PHP Update Log: PHP 4.3: new base parameters.


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