(PHP 4, PHP 5)
mt_getrandmax — 显示随机数的最大可能值
返回调用 mt_rand() 所能返回的最大的随机数。
Example #1 计算一个随机浮点数
<?php
function randomFloat($min = 0, $max = 1) {
return $min + mt_rand() / mt_getrandmax() * ($max - $min);
}
var_dump(randomFloat());
var_dump(randomFloat(2, 20));
?>
以上例程的输出类似于：
float(0.91601131712832) float(16.511210331931)
Anonymous (2013-05-13 12:40:56)
The max on a Windows 7 x64 machine is also 2147483647.
marcus at synchromedia dot co dot uk (2011-08-10 13:41:57)
On both 32 and 64-bit systems (OS X and Linux), mt_getrandmax() returns 2147483647 for me, i.e. ~2^31.