   #PHP Manual Mathematical Functions mt_getrandmax mt_srand

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                                    mt_rand

   (PHP 3>= 3.0.6, PHP 4 )
   mt_rand -- Generate a better random value

Description

   int mt_rand ( [int min, int max])

   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 that should be suitable for seeding some kinds of
   cryptography (see the home page for details) and is four times faster
   than what the average libc provides.

   If called without the optional min, max arguments mt_rand() returns a
   pseudo-random value between 0 and RAND_MAX. If you want a random
   number between 5 and 15 (inclusive), for example, use mt_rand (5, 15).

   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

     Note: As of PHP 4.2.0, there is no need to seed the random number
     generator with srand() or mt_srand() as this is now done
     automatically.

     Note: In versions before 3.0.7 the meaning of max was range. To get
     the same results in these versions the short example should be
     mt_rand (5, 11) to get a random number between 5 and 15.

   See also mt_srand(), mt_getrandmax() and rand().
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