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PHP Quiz PHP CertificatePHP mt_srand() Function
Complete PHP Math Reference
Definition and Usage
The mt_srand() function seeds the random number generator for mt_rand().
This function should be called only once per script, and it must be called before any calls to mt_rand().
Syntax
mt_srand(seed)
| Parameter | Description |
|---|---|
| seed | Optional. Seed number for the random number generator. If omitted, a random value is used. |
Tips and Notes
Note: In PHP 4.2.0 and later, there is no need to seed the random generator with mt_srand(). This is done automatically.
Tip: The greater the randomness of the seed, the more random number you'll get. A suitable number to seed this function with, is mktime().
Example
In this example we will seed the random number generator:
<?php
mt_srand(mktime());
echo(mt_rand());
?>
mt_srand(mktime());
echo(mt_rand());
?>
The output of the code above could be:
1132656473
Complete PHP Math Reference
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