Re: rand() function
| From: | Ed Vul | Date: | Fri, 07 Jul 2000 16:05:36 +0000 |
| Subject: | Re: rand() function | ||
| References: | 1 2 3 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-5399@lists.php.net to get a copy of this message | ||
nevermind, I found the code for the mt_rand() function and that's quite over
my head, so I'm assuming rand() is as well, thanks.
Ed
""Ed Vul"" <edv@whitepj.com> wrote in message
news:8k4ukt$8cu$1@toye.php.net...
> Yup, thanks guys, that was my problem. I completely looked over the
srand()
> part in the manual.
> One more question though:
> What does rand() do to the seed? or are the algorithms or whatever it
uses
> way over my head?
> Thanks
> Ed
>
> "Kris Dahl" <krislists@toolhouse.com> wrote in message
> news:B58A797A.8A85%krislists@toolhouse.com...
> > on 7/6/00 5:36 PM, David VanHorn at dvanhorn@cedar.net wrote:
> >
> > > Shouldn't you seed the random generator?
> > >
> > > Here's what I use to generate random cookies. So far, they look pretty
> > > daggone random.
> > >
> > > srand(date("s"));
> >
> > I don't think a seed of date("s") is going to give him the level of
> > precision that is necessary for a recursively generated random number.
> >
> > I.e. if it is executed several times in one second (as a loop like this
> > would be) it would do exactly what it is doing now. I believe that in
PHP
> > rand seeds itself with the date function if you don't seed it yourself
> > (other wise it would always return the same 'random' number)... so I
would
> > wager that it would do the exact same thing.
> >
> > Try seeding it with something like
> > srand((double)microtime()*1000000);
> > which is actually what they suggest in the PHP manual.
> >
> > -k
> >
> >
> >
> >
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