Hacker News Reader

Comment by palish | Hacker News Reader

RNG's... Did they include Mersenne Twister?

http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html

EDIT: Apologies... the only reason I asked was to contribute to the discussion, but now I realize it probably looked like I was being lazy.

View on HN

Yes - there are several options, which MT is one of: http://en.wikipedia.org/wiki/C_0x#Extensible_random_number_f...

Mersenne Twister is hardly perfect. It's slow, causes a lot of cache misses, and IIRC the output is purely XOR of previous outputs. Do people just bring it up because they like the name?

Deserved or not, Mersenne Twister is somewhat famous among laymen like myself for being very fast relative to it's reasonably high quality. If you can point me at an RNG that is both faster and higher quality, I will be genuinely in your debt.

My layman's understanding is that George Marsaglia's xorshift generator[1] is considerably faster than the Mersenne Twister while still providing high quality randomness.

I've also seen WELL512[2] mentioned in a few places, but I don't know much more about it than the name.

[1]: First introduced here: http://groups.google.com/group/comp.lang.c/msg/e3c4ea1169e46...

[2]: http://www.iro.umontreal.ca/~panneton/WELLRNG.html

Let me know if you are ever in San Francisco and I'll open the tab at one of our many fine beer-snob bars (or a wine-snob bar, if you prefer).

This thread & invite is still open to anyone who can provide further suggestions!

Reply on news.ycombinator.com