(j3.2006) (SC22WG5.4105) [ukfortran] Standard intrinsics and coarrays
Thu Oct 22 01:16:31 EDT 2009
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.
................................Malcolm Cohen, Nihon NAG, Tokyo.
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