SMS scnews item created by Bill Unger at Tue 12 Jun 2007 1511
Type: Seminar
Distribution: World
Expiry: 14 Jun 2007
Calendar1: 14 Jun 2007 1430-1700
CalLoc1: Carslaw 535A

Computational Algebra Seminar: Shparlinski, Brent

Speaker: Igor Shparlinski (Macquarie)
Title: TBA
Time & Place: 2:35-3:30pm, Thursday 14 June, Carslaw 535

Afternoon Tea: 3:30-4pm

Speaker: Richard Brent (ANU)
Title: Using Magma to find good xorshift random number generators
Time & Place: 4:05-5pm, Thursday 14 June, Carslaw 535

Abstract (Brent):
Marsaglia recently introduced a class of ``xorshift’’ random number
generators (RNGs) with periods $2^n - 1$ for $n = 32, 64$, etc. We
describe a generalisation of Marsaglia’s xorshift generators in order
to obtain fast and high-quality RNGs with extremely long periods.

RNGs based on primitive trinomials may be unsatisfactory because a
trinomial has very small weight (number of nonzero terms).  In
contrast, our generators can be chosen so that their minimal
polynomials have large weight. A search using Magma has found good
generators for $n$ a power of two up to 4096.  These have been
implemented in a free software package xorgens.  Aspects of the search
using Magma, and a connection with Fermat numbers, will be mentioned.

ball Calendar (ICS file) download, for import into your favourite calendar application
ball UNCLUTTER for printing
ball AUTHENTICATE to mark the scnews item as read
School members may try to .