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From: "Malcolm Cohen" <malcolm@nag-j.co.jp>
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Subject: Re: [ukfortran] (SC22WG5.4104) (j3.2006) Standard	intrinsics	and coarrays
Date: Thu, 22 Oct 2009 14:16:31 +0900
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Aleksandar Donev wrote:
> In the case of a "shared" generator, I am not sure I understand exactly what 
> is meant, guaranteed, or processor dependent. Is it obvious to others and I am 
> just being dense?

Yes it is obvious.

In a "shared" generator there is a single seed and a single sequence.  Images 
take values from that single sequence.

In a "separate" generator, each image has a seed and a sequence.  Each image 
takes values from its own sequence.

It is trivial to discover this by careful syncing between two images and a 
sequence of random_seed and random_number calls.

>    It is processor dependent whether all images use a common
>    generator or whether each image uses a separate one.

Perhaps we should require that it should be one or the other.

Cheers,
-- 
................................Malcolm Cohen, Nihon NAG, Tokyo.