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Re: Randomu seed initialization [message #68611 is a reply to message #68610]

Thu, 12 November 2009 12:32

Matt[2]
Messages: 69
Registered: March 2007

Member

Jeremy Bailin <astroconst@gmail.com> writes:

> If I had to speculate, I'd say that the variable that you're passing
> as the seed isn't undefined like you think it is. Have you tried doing
> a "help, seed" right before the randomu call?

If I was going to speculate, I would guess the undefined seed gets set
to the same value internally every time. Thereby starting the same
string of pseudo-random numbers.

I usually use:
seed = long(systime(/seconds) )

To initialize my seed. It's not perfect, but it's a start.

Also remember from the docs: "Each independent random number sequence
should maintain its own state variable. To maintain a state over
repeated calls to a procedure, the seed variable may be stored in a
COMMON block."

Matt

--
Matthew Savoie - Scientific Programmer
National Snow and Ice Data Center
(303) 735-0785 http://nsidc.org

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[Message index]

		Re: Randomu seed initialization By: Conor on Fri, 13 November 2009 08:31
		Re: Randomu seed initialization By: pgrigis on Thu, 12 November 2009 13:59
		Re: Randomu seed initialization By: Chris[6] on Thu, 12 November 2009 13:49
		Re: Randomu seed initialization By: Matt[2] on Thu, 12 November 2009 12:32
		Re: Randomu seed initialization By: Jeremy Bailin on Thu, 12 November 2009 11:31
		Re: Randomu seed initialization By: Conor on Thu, 12 November 2009 05:59
		Re: Randomu seed initialization By: penteado on Wed, 11 November 2009 12:22

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