Re: mt_rand() - the same forever?

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Janek wrote:
On Sun, Oct 5, 2008 at 10:05 PM, Ashley Sheridan
<ash@xxxxxxxxxxxxxxxxxxxx> wrote:
On Sun, 2008-10-05 at 21:57 +0200, Janek wrote:
I know, but I *want* to seed it. My goal is to have a fixed
pseudorandom sequence for each integer (seed) and I don't want those
sequences to change regarding PHP version.

Janek

On Sun, Oct 5, 2008 at 9:52 PM, Richard Heyes <richard@xxxxxxx> wrote:
I wonder whether I can rely on the stability of mt_srand() and
mt_rand(). I want them to generate the same sequence for a fixed seed,
regardless of PHP version. Do you think I can trust it?
Janek
Keep in mind (if you're not already) that mt_rand() doesn't
technically need to be seeded.

--
Richard Heyes

HTML5 Graphing for FF, Chrome, Opera and Safari:
http://www.phpguru.org/RGraph

Doesn't it also rely on the system clock as well?


Ash
www.ashleysheridan.co.uk



No. When I give a fixed seed to mt_srand(), each time I get the same
sequence of mt_rand()s. My question is wheather the actual algorithm
behind these functions is likely to change in the next version of PHP
or not.

Janek

why not give us your code and expected results, a few of us can run it on our various php installs and post back the results.

No other way to find out for sure!

--
nathan ( nathan@xxxxxxxxxxx )
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  php + java + flex + xmpp + xml + ecmascript
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