Re: ceerano and the seed

[Vernon Hamberg <vhamberg@xxxxxxxxx>]

Peter

I'm not sure of the context. The usage instructions for CEERAN0 say that
the seed should be a non-negative integer between 0 and 2,147,483,646. Zero
makes it generate its own seed from the GMT at the time the function is
called. And it returns a value that can be used as the next seed. Of
course, the new seed is generated by the original process, hence, as Leif
says, it might not be that good an idea to use it. That was why I suggested
using 0, as that forces a somewhat unpredictable value for the seed each time.

Are you speaking of the theory of generating pseudorandom numbers, that
uses a couple large relatively prime numbers? Am I anywhere close? I've
never studied the theory that closely, I just want a function I can use
that I can trust to generate even distributions.

The rand() function in SQL can take a seed or not. Without a seed (a
smallint or integer) it must generate its own seed, as it starts with a
different sequence each time. If you use a seed, such as rand(100), the
sequence of random floating point numbers is the same each time, as is
expected. CEERAN0 has the same behavior

Vern

At 10:17 PM 9/16/02 -0400, you wrote:
> Vernon,
>
> I always thought the seed should be a large prime number.
>
> Peter.
>
> _______________________________________________
> This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
> To post a message email: MIDRANGE-L@midrange.com
> To subscribe, unsubscribe, or change list options,
> visit: http://lists.midrange.com/cgi-bin/listinfo/midrange-l
> or email: MIDRANGE-L-request@midrange.com
> Before posting, please take a moment to review the archives
> at http://archive.midrange.com/midrange-l.