(3.0.6 - 3.0.18 only, PHP 4 >= 4.0.0)
mt_rand -- Generate a better random value
Description
int mt_rand (void)
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. mt_rand() function is a drop-in replacement
for this. It uses a random number generator with known characteristics, the Mersenne Twister, which
will produce random numbers that should be suitable for seeding some kinds of cryptography (see the
home pages for details) and is four times faster than what the average libc provides. The Homepage
of the Mersenne Twister can be found at http://www.math.keio.ac.jp/~matumoto/emt.html, and an optimized version of the MT
source is available from
http://www.scp.syr.edu/~marc/hawk/twister.html .
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).
Remember to seed the random number generator before use with mt_srand().
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(),
srand(), rand() and getrandmax().
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