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From: Peter Perkins on 7 Jun 2010 13:51
On 6/7/2010 9:27 AM, Walter Roberson wrote:
> Peter Perkins wrote:
>> Randima, the generators in MATLAB accept an integer value between 0
>> and 2^31 as a seed
>
> Not 2^31:

Walter, you're right. I hit the wrong key.

> The limits on seed can be tricky to find in the documentation -- they
> are not documented in @RandStream or rand() or Legacy Mode :: Random
> Numbers ( techdoc/math/brt5wsv.html ), but they are documented in
> RandStream (without the @) and in RandStream.create.

I think the allowable values for a seed are documented on both of the
reference pages where a seed is accepted as an input to create a stream,
which is to say the constructor and the create method, though not on the
reference page for the reset method. You're right that both "Seed must
be an integer less than 2^32" and "Seeds must be an integer between 0
and 2^32" are not precise enough. I've made a note to fix all of that,
thanks for pointing them out.
From: Walter Roberson on 7 Jun 2010 14:28
Peter Perkins wrote:

> I think the allowable values for a seed are documented on both of the
> reference pages where a seed is accepted as an input to create a stream,
> which is to say the constructor and the create method, though not on the
> reference page for the reset method.

There are three pages (at least) that show the construction of a stream, with
the third one being "Legacy Mode :: Random Numbers", which does not document
the limits on the seeds.

I see the logic now behind not having the seed limit in @RandStream . On the
other hand, he rand() documentation section that mentions legacy mode refers
the user to @RandStream for new work, and I think a lot of people are going to
miss the distinction between the @RandStream and RandStream (constructor)
documentation and think it is just another self-referential page (the rand()
page is self referential.)
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