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Mail Archives: djgpp/2007/09/05/11:21:23

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Subject: Re: random() : What am I doing wrong?
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DJ Delorie <dj AT delorie DOT com> wrote on 09/05/2007 09:11:13 AM:

# > That depends if you care about equidistribution; if you do, you'd be
# > better off
#
# ... not using random() in the first place.

Fair enough :)
I can recommend the Mersenne Twister for this, if anyone cares...

# This has *exactly* the same problem, it just involves different
# numbers being weighted heavier.
#
# If you really want equidistribution, you have to check for the last
# couple of numbers, and call random() again if you get them.

Well, okay - random() doesn't anything like guarantee
equidistribution.  But that said, wouldn't scaling the result set
at least not give you anything *worse* than what you started with?

(I freely admit that we're pushing the bounds of what I know here,
so this isn't meant as a challenge, but rather the possibility of
learning something...)

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