Curriculum Vitæ
Research interests:
combinatorial games |
fraction-free computation of determinants |
Gröbner basis computation |
- Ideal Nim (a generalization of Chomp)
|
- methods of Dodgson and Bareiss
- Double-Crossing Method
- Extended Dodgson’s Method
|
- dynamic algorithms
- signature-based algorithms (inspired by Faugère’s F5)
- extended criteria for skipping S-polynomial reduction
|
Sample posters:
Posters are unrefereed, and by their nature contain out-of-date information.
Refereed publications:
- 2020
- 2017
- 2016
- 2014
- 2011
-
-
- 2010
- 2007
- 2005
- Combinatorial Criteria for Gröbner Bases
(PhD dissertation: PDF)
Preprints:
Preprints on
arxiv.org
have not been refereed, unless otherwise noted. My page on arxiv is
here.
- F4/5 (joint with Martin Albrecht)
More on the way...
Students:
- Undergraduate students
- Haley Dozier, Ideal Nim (2013-2014)
- Matthew Dixon, Tropical Mathematics (2010)
- Lorrin Debenport, Triangularizing matrices without swapping columns, Honors Thesis (2011)
- Elisabeth Palchak, A criterion for identifying stressors in non-linear equations using Gröbner bases, Honors Thesis (2010)
(Lisa also participated in an REU at the University of Georgia)
- Ashley Sanders, College Math Journal Problems 866 and 871, an implementation of a double-crossing method of computing determinants (2008-2009)
- Deanna Leggett, Dodgson’s
method of computing determinants (2007-2008), see also this preprint
- Courtney Bright, Factors
impacting the poor performance of mathematics students in the United
States, Honors Thesis (2008)
- Lenton McLendon, Introduction to Gröbner bases (2007)
- Jonathan O’Rourke, Universal
Algebra, with Dr. Lee (2006)
- Graduate students
- Shannon Ryle, PhD student (2014, changed adviser)
- Deanna Leggett, Fraction-free computation of determinants, Master’s Thesis (2011)
(Deanna’s paper won first prize at the 2011 meeting of the LA/MS Section of the MAA)
- Miao Yu, An F4-style Involutive Basis algorithm, Master’s Thesis (2010)
(Miao’s paper won first prize at the 2010 meeting of the LA/MS Section of the MAA)
Samples of talks:
Software:
All software is open source, unless otherwise noted.
I contribute to other projects when I can, and have in the past contributed
material to
LyX (at least one document format),
jEdit (format for the Maple language), and
Sage
(see
here, but mostly I contributed to the MILP and Singular modules).
- Dynamic Gröbner basis computation with new criteria
- DynGB
- (latest) upload of 14 March 2017 corrects errors in Makefile; provides a few enhancements hither, thither, and yon; and corrects an error in geobucket construction that I thought I fixed with the 11 Feb update, though in fact I merely made it worse without noticing
- upload of 11 February 2017 corrects errors in examples that sometimes caused a hang
- dynamic_algorithm.pyx
uploaded 2 November 2012
- Embedded Vector Analysis
- "Toy/demonstration" implementations of F5 based on this pseudocode
and this variant
(last updated
January 2009)
- in Singular
(joint work with Christian Eder)
- f5ex.lib
uploaded
November 2008; revised January 2009; latest version June 2009
(example systems; you need this or the other libraries will complain)
- f5_library.lib
uploaded May
2008; revised January 2009; latest version June 2009
(F5, F5R, and F5C: use commands basis, basis_r, and basis_c)
- f5r_library.lib
uploaded
November 2008; obsolete (incorporated into f5_library.lib)
- f5c_library.lib
uploaded
November 2008; obsolete (incorporated into f5_library.lib)
- Changes
to Till Steger’s Magma implementation,
which when implemented cause it to terminate on the non-terminating
example in that implementation
uploaded 13 June
2009
- in Sage
- f5_arri.py
uploaded December 2010
- staggered_linear_basis.py
uploaded December 2010
- f5.py
uploaded
November 2008; latest version June 2009 (there was a bug in the January
2009 version)
(primarily Martin Albrecht’s code)
- f5.pyx
uploaded
November 2008
(entirely Simon King’s code)
- f5_sugar.py
uploaded
November 2008
(an experimental version based on Albrecht’s code to see whether F5 and
Sugar would play together; unfortunately this will remain slow unless I
find a way to make Sage and/or Singular report the quotients from
polynomial division, not just the remainder)
- in Maple: F5_module.mw
uploaded July
2007; latest version 26 September 2007
(this version is quite slow
and unmaintained)
- Maple:
- plotacceptableregions3d.mpl
A Maplet to plot regions that satisfy the criterion described
in the joint paper with Hoon Hong, above. Public domain.
last
update/big
fix: 14
September 2004
- GBDetection.mw
A Maple
worksheet and module implementing a criterion for detection of a
Gröbner basis of two polynomials, using an algorithm from the
dissertation above.
last
update/bug fix: 19 November 2007
- efc_buchberger_module.mw
An implementation of Buchberger’s algorithm, using a new criterion for
skipping S-polynomial
reductions from a paper I have submitted for publication. The most
recent version includes a comparison with the Gebauer-Möller
algorithm. GPL.
uploaded 10 July
2007; latest version 23 November 2007
- SmartEiffel:
(requires the 1.1 version of the SmartEiffel
compiler)
- SPolys.tar.gz
Public domain.
last
update/bug fix: 12 August 2004
(This has seen some work and upgrading since then, but I haven’t
checked the new version for release. I’ll do that if someone asks.)
- html_css
scripts for SmartEiffel’s short
tool
Teaching-oriented
Apps for
Android devices
Associations:
Past
Service:
- coordinator, NCSU Graduate Algebra Seminar, Fall 2001
Illustrations of research:
If you have
questions or suggestions or bug reports, please do
contact me.