PS There is also a version of this by Pauli in 1998 ANTS:
http://www.springerlink.com/content/hc6nln8ghvgctl6m/

2009/3/6 John Cremona <john.crem...@gmail.com>:
> Sage does not do this as far as I know but my student David Roberts
> implemented it in Magma for his thesis.  He was following an
> alternative treatment by Mulders and Storjohann (the latter spoke at
> Sage Days in Nancy) since I did not know Arjen Lenstra's essentially
> equivalent formulation until I gave a talk in Leiden with Hendrik L in
> the audience ;).
>
> The algorithm is the same for polynomial lattices over any field, but
> in the smae way as for polynomial gcd and the Euclidean Algorithm, it
> works better over some fields than others (e.g. finite fields good,
> rationals bad).  I would guess that it could be implemented more
> efficiently over GF(2).
>
> John Cremona
>
> PS See http://www.warwick.ac.uk/staff/J.E.Cremona/theses/index.html
> for the thesis (it's the last one)
>
> PS I have paper copy (only) of the Lenstra paper
>
> 2009/3/6 Ryan Hinton <iob...@email.com>:
>>
>> Thanks in advance for any help.  Please let me know if I'm producing too
>> much noise on the list.
>>
>> I'm still working on the pseudo-random number generators.  To verify a
>> certain property (maximal equidistribution) [1], it is equivalent [2,3]
>> to finding a Minkowski-reduced basis for a lattice over polynomials with
>> coefficients in GF(2) (specifically, the non-zero point with the
>> smallest maximum polynomial degree).  They give [4] as an example of an
>> algorithm that will do the trick.
>>
>> I'm stuck.  I have not yet found a copy of [4], but from the abstract it
>> sounds like the reduced lattice basis is a means to the title of the
>> paper, factoring multivariate polynomials over finite fields.  On IRC,
>> Carl Witty suggested that the LLL algorithm sounded similar, but for
>> integers.  I haven't figured out how to frame my polynomial lattice
>> problem as an integer lattice problem, though.
>>
>> So, question #1.  Does anyone know if Sage does this?
>>
>> Question #2.  Does anyone have electronic access to article [4] or an
>> improved algorithm to do this basis reduction?  The ScienceDirect link
>> for the Lenstra article is is
>> http://dx.doi.org/10.1016/0022-0000(85)90016-9.
>>
>> Thanks!
>>
>> References:
>>
>> Most of these are on Dr. L'Ecuyer's website,
>> http://www.iro.umontreal.ca/~lecuyer/papers.html
>>
>> [1] F. Panneton, P. L'Ecuyer, and M. Matsumoto, ``Improved Long-Period
>> Generators Based on Linear Recurrences Modulo 2'', ACM Transactions on
>> Mathematical Software, 32, 1 (2006), 1-16.
>>
>> [2] P. L'Ecuyer and F. Panneton, ``F_2-Linear Random Number
>> Generators'', 2007, to appear with minor revisions in "Advancing the
>> Frontiers of Simulation: A Festschrift in Honor of George S. Fishman."
>> GERAD Report 2007-21.
>>
>> [3] R. Couture and P. L'Ecuyer, ``Lattice Computations for Random
>> Numbers'', Mathematics of Computation, 69, 230 (2000), 757--765.
>>
>> [4] A. K. Lenstra. Factoring multivariate polynomials over finite
>> fields. Journal of Computer and System Sciences, 30:235–248, 1985.
>>
>> ---
>> Ryan Hinton
>> PhD candidate, Electrical Engineering
>> University of Virginia
>>
>> >>
>>
>

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