mt_rand
(PHP 4, PHP 5)
mt_rand — Generate a better random value
Description
Many random number generators of older libcs have dubious or unknown characteristics and are slow. By default, PHP uses the libc random number generator with the rand() function. The mt_rand() function is a drop-in replacement for this. It uses a random number generator with known characteristics using the » Mersenne Twister, which will produce random numbers four times faster than what the average libc rand() provides.
If called without the optional min, max arguments mt_rand() returns a pseudo-random value between 0 and mt_getrandmax(). If you want a random number between 5 and 15 (inclusive), for example, use mt_rand(5, 15).
Parameters
- min
-
Optional lowest value to be returned (default: 0)
- max
-
Optional highest value to be returned (default: mt_getrandmax())
Return Values
A random integer value between min (or 0) and max (or mt_getrandmax(), inclusive)
Changelog
| Version | Description |
|---|---|
| 4.2.0 | The random number generator is seeded automatically. |
Examples
Example #1 mt_rand() example
<?php
echo mt_rand() . "\n";
echo mt_rand() . "\n";
echo mt_rand(5, 15);
?>
The above example will output something similar to:
1604716014 1478613278 6
See Also
- mt_srand() - Seed the better random number generator
- mt_getrandmax() - Show largest possible random value
- rand() - Generate a random integer