(PHP 8 >= 8.2.0)
Random\Engine\Xoshiro256StarStar::__construct — Constructs a new xoshiro256** engine
$seed
= null
)
本函数还未编写文档,仅有参数列表。
seed
How the internal 256 bit (32 byte) state consisting of four unsigned 64 bit integers is
seeded depends on the type used as the seed
.
Type | 说明 |
---|---|
null | Fills the state with 32 random bytes generated using the CSPRNG. |
int |
Fills the state with four consecutive values generated with the SplitMix64 algorithm
that was seeded with seed interpreted as an unsigned 64 bit integer.
|
string | Fills the state by interpreting a 32 byte string as four little-endian unsigned 64 bit integers. |
seed
is
not 32 bytes, a ValueError will be thrown.
seed
consists of
32 NUL bytes ("\x00"
), a ValueError
will be thrown.
示例 #1 Random\Engine\Xoshiro256StarStar::__construct() example
<?php
// Uses a random 256 Bit seed.
$e = new \Random\Engine\Xoshiro256StarStar();
$r = new \Random\Randomizer($e);
?>
示例 #2 Deriving a seed from a string
<?php
$string = "My string seed";
// Hash the string with SHA-256 using binary output to turn the
// $string into a 256 Bit seed. Using the same string will result
// in the same sequence of randomness.
$e = new \Random\Engine\Xoshiro256StarStar(
hash('sha256', $string, binary: true)
);
echo bin2hex($e->generate()), "\n";
?>
以上示例会输出:
6e013453678388c2