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Re: generating random numbers -- what seeds to use?
From: |
Bob Bailey |
Subject: |
Re: generating random numbers -- what seeds to use? |
Date: |
Mon, 28 Apr 2003 09:53:22 +0800 |
If you want truly random numbers (but not huge quantities),
check out Hotbits at
http://www.fourmilab.ch/hotbits
These can at least provide random seeds for rn algorithms.
You never need to use correlated seeds again!
Also, the GNU Scientific Library has quite a number of
the best rn generators. It's not Octave/Matlab, but if you
just want files of rn's, why must you use O/M?
http://www.gnu.org/software/gsl
Bob Bailey
----- Original Message -----
From: "John W. Eaton" <address@hidden>
To: "Mike Miller" <address@hidden>
Cc: "Help-Octave List" <address@hidden>
Sent: Monday, April 28, 2003 9:03 AM
Subject: generating random numbers -- what seeds to use?
> On 27-Apr-2003, Mike Miller <address@hidden> wrote:
>
> | I need to create large amounts of random data under a certain model. I
> | wanted to produce 10,000 files, so I set 10 different processors to the
> | task of executing an octave scrit that would make 1,000 files.
> | Unfortunately, I forgot that some of the jobs were starting at nearly the
> | same moment, so they took the same seed from the clock and produced the
> | same 'random' files!
> |
> | I'd still like to run 10 jobs at once, but I'll have to supply initial
> | seeds. Is there any way that I can guarantee that I won't produce the
> | same file twice? What is the best way to choose seeds? What is the
> | period for Octave's random number generator? Has anyone developed other
> | random number generators for Octave?
>
> Why not generate all the random numbers in advance? For example, for
> N random numbers in each of M files, something like
>
> for i = 1:M
> f = fopen (sprintf ("rnd-%d", i), "w");
> fwrite (f, rand (N, 1), "double");
> fclose (f);
> endfor
>
> Then you could read these files for your data generation processes.
>
> jwe
>
>
>
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