Re: Random numbers generation

[Thomas Walter <t.walter@nefkom.net>]

Hi Yannick,

On Thu, 2005-12-08 at 21:45, Yannick Patois wrote:
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> Thomas Walter wrote:
> > On Thu, 2005-12-08 at 00:22, Stuart Prescott wrote:
> >>The GSL documentation talks a bit about the different generators
> >>available and I highly recommend some of the references therein (Park &
> >>Miller and L'Ecuyer in particular). 
> >>	http://www.gnu.org/software/gsl/manual/gsl-ref_17.html
> 
> > Just for completeness to the random generators mentioned above.
> > If your system has '/dev/random' and/or '/dev/urandom' then you have
> > also a good random to read from.  This is feed by several non
> > deterministic data available on your system.  The more usage and traffic
> > you have, the better.
> 
> Those random generators have to be avoided, except in very specific
> cases as they are not reproducable; there is no way to replay them.
> 


That's the definition of random -- you do not know what's comming next
and no chance to repeat.
Some random-generator algorithms are very good to show no pattern.
Even in a higher dimension space.

But true random has no pattern, no matter how long and good you look at.
Another try may be a chaotic system, but I do not know.

If you want a replay then simply remember the sequence.
Or prepare the sequence by anything you want and then feed it into your
application.  That seems to be the best approach as the using
application is independent from source of "random" varying from poor til
true.

Kind Regards,
Thomas