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mt_rand is a function that PHP has had since its inception

藏色散人
藏色散人Original
2021-12-14 10:25:391297browse

mt_rand is a function available since php4.2.0. This function is used to generate better random numbers. The syntax is "mt_rand(): int" or "mt_rand(int $min, int $max): int".

mt_rand is a function that PHP has had since its inception

#The operating environment of this article: Windows 7 system, PHP version 7.4, Dell G3 computer.

mt_rand is a function that PHP has since its inception?

Since PHP 4.2.0, it is no longer necessary to seed the random number generator with the srand() or mt_srand() functions, it is now done automatically. In versions prior to 3.0.7, max meant range . To get the same random numbers from 5 to 15 as in the above example in these versions, the short example is mt_rand (5, 11).

mt_rand

(PHP 4, PHP 5, PHP 7, PHP 8)

mt_rand — Generate better random numbers

Description

mt_rand(): int
mt_rand(int $min, int $max): int

Many old libc random number generators have some uncertain and unknown characteristics and are very slow. PHP's rand() function uses the libc random number generator by default. The mt_rand() function is informally used to replace it. This function uses the known features of » Mersenne Twister as a random number generator, which can generate random values ​​on average four times faster than rand() provided by libc.

If the optional parameters min and max are not provided, mt_rand() returns a pseudo-random number between 0 and mt_getrandmax(). For example, if you want a random number between 5 and 15 (inclusive), use mt_rand(5, 15).

Parameters

min

Optional, the minimum value returned (default: 0)

max

Optional, The maximum value returned (default: mt_getrandmax())

Return value

Return a random integer between min (or 0) and max (or to mt_getrandmax(), including this value) .

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