PHP log1p()Function

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Examples

Returns log(1+number) for different numbers:

<?php
echo(log1p(2.7183) . "<br>");
echo(log1p(2) . "<br>");
echo(log1p(1) . "<br>");
echo(log1p(0));
?>

Run Example »

Definition and Usage

The log1p() function returns log(1+number), even whennumberthe value is close to zero, it can calculate an accurate result.


Syntax

log1p(number);

Parameters Description
number Required. Specifies the number to process.

Technical Details

Return value: log(1+number)
Return type: Float
PHP version: 4.1+
PHP Changelog: PHP 5.3: The log1p() function is available on all platforms.


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