This is the mail archive of the
gsl-discuss@sources.redhat.com
mailing list for the GSL project.
Re: RN generators Seed
- From: Jeff Spirko <spirko at Lehigh dot EDU>
- To: Maura Edeweiss Monville <memonvil at artsci dot wustl dot edu>
- Cc: gsl-discuss at sources dot redhat dot com
- Date: Tue, 26 Aug 2003 09:28:35 -0400
- Subject: Re: RN generators Seed
- References: <Pine.GSO.4.53.0308260014380.10777@ascc.artsci.wustl.edu>
On Tue, Aug 26, 2003 at 12:15:27AM -0500, Maura Edeweiss Monville wrote:
> I'm currently using a RNG from the GNU Scietific Library in my simulation
> I need to rerun my simulation many times with different seeds.
> A friend of mine states the following:
> "You can use the final random seed of a run as the starting random seed of
> the next run (as you probably know, the random generators usually start
> with a seed and then modify it in the process of generating random
> numbers, so essentially the seed becomes a random number itself)"
> I wonder how the final seed value can be obtained when using GSL Random??
> Number Generators .... I only found the possibility to read and save the?
> RNG "status". I do not know the relation between the RNG "status" and the
> RNG "seed" ...???? Can anyone help in this regards ?
I don't know the exact answer to your question, but I do have some
suggestions. I often use the current time in seconds to seed an
RNG. There is a slight problem with this. If one simulation (or in
my case, setting up a simulation) takes less than a second, two runs
may use the same seed. I ended up switching to using the bash
shell's $RANDOM variable. It's limited to 16-bits, but it could be
combined with the time to get a better starting seed.
--
Jeff Spirko spirko@lehigh.edu spirko@yahoo.com WD3V |=>
The study of non-linear physics is like the study of non-elephant biology.
All theoretical chemistry is really physics;
and all theoretical chemists know it. -- Richard P. Feynman