Re: The probability of returning zero by math.random is doubled.

[Gé Weijers <ge@...>]

> Don't forget about the Tausworthe generators. They can provide
> long periods with a small amount of state space:
>
>   http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps

The Tausworthe generators are absolutely good enough for a general  
purpose RNG. Initializing these generators (and the Well and Mersenne  
Twister generators) takes a bit of care, though. My implementation of  
the Well generator uses a block cipher to generate well-distributed  
bits that initialize the RNG.

Prof. Richard Brent has published GPL source code for his fast maximum  
period (up to 2^4096-1 bits) RNG, and this includes an effective  
initialization procedure. It's worth a look, esp. because you could  
use the initialization procedure for other RNGs as well. I am working  
on a Lua DLL that uses new implementation of this RNG. It seems to be  
as good as the Well generator, but it's faster.

http://wwwmaths.anu.edu.au/~brent/pub/pub224.html

Gé

--
Gé Weijers
ge@weijers.org