Some questions about random/1 and frandom/1

From: josh singer <>
Date: Mon 06 Oct 2003 09:06:55 AM GMT
Message-ID: <3E899FAFBF56D611B6A500508B9A9DA234297A@LON-SRV2>
Hi folks, 

The documentation for frandom/1 mentions that it is based on the Park-Miller
generator. Is random/1 (the integer version) based on the same generator?

In theory at least, to get the properties (long period / low correlation
etc.) of the Park-Miller generator for several runs, I believe the seed of
the i'th of an algorithm run should be initialised from wherever the seed
got to at the end of the i-1'th run. For this to be practical in ECLiPSe
we'd need some kind of get_seed/1 predicate to query the current seed value,
so that we can store this number and thereby repeat any run we like. Any
chance of such a feature in 5.7?

I'm not saying this makes a lot of difference in practice, but since we've
gone to the effort of building a good random number generator library, we
may as well get the most out of it.



Josh Singer

Software Developer, Parc Technologies Limited
Tel. +44 (0)207 261 4067

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Received on Mon Oct 06 10:14:11 2003

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