Thread: RAND()
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Old 05-02-2008, 05:05 AM
Nick Wedd
 
Posts: n/a
Default Re: RAND()

In message <69qdnTw3ffk8Z4TVnZ2dnUVZ_qfinZ2d@comcast.com>, Jerry Stuckle
<jstucklex@attglobal.net> writes
>Nick Wedd wrote:
>> In message <n8GdnZSDT8M7gIrVnZ2dnUVZ_vKdnZ2d@comcast.com>, Jerry
>>Stuckle <jstucklex@attglobal.net> writes
>>> Cosmic programmer wrote:
>>>> How good is the rand function of MySQL? How can it be improved?
>>>> Thx.
>>>> --
>>>> When you argue with a fool, chances are he's doing the same
>>>
>>> It's as good as pretty much any pseudo-random number generator. Why
>>>do you think it needs to be improved?

>> If it's only as good as any pseudo-random number generator, it
>>definitely needs to be improved.
>> Nick
>>

>
>And exactly how would you do that? Most pseudo-random number
>generators are pretty good, IMHO. And there is no such thing as a true
>random number generator.


Knuth's "Numerical recipes in C" explains what can be wrong with
system-supplied rand() functions. He wrote it 20 years ago, and things
must have improved since then; but I still wouldn't trust a
system-supplied rand(). He gives code for improving a system rand(),
also for replacing it by one known to be good. His code is in C of
course, but is quite short and is easily translated into other
languages.

Nick
--
Nick Wedd nick@maproom.co.uk
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