Symbolic and algebraic computation, in particular solving equations
(symbolically and numerically), system development, limit and series
computation and heuristic algorithms.
Co-founder in 1980 of the Symbolic Computation Group at the University
of Waterloo, the research group that produced Maple.
(SCG).
Computational Biochemistry algorithms.
Director of the Computational Biochemistry Research Group
CBRG.
Development of the Darwin system and server for these computations.
Design and analysis of algorithms, in particular searching, text searching
and sorting algorithms.
New Oxford English Dictionary project at the University of Waterloo,
co-founder in 1984 of the
Centre for the New OED.
Vice president and member of the Steering Committee of the
OpenMath Society, a project which
aims at developing a standard character-based communication protocol for
mathematical objects.
Paper
at the 6^{th} OpenMath Workshop, Zürich, July 1996
Paper presented
at the 8^{th} OpenMath Workshop, Nice, May 23-24, 1997.
A programming CD.
Minutes of the discussions
at the 6^{th} OpenMath Workshop, Zürich, July 1996
Protein identification from the molecular weight of its fragments
Heidelberg, Dec. 3, 1992 (and at other invited talks)
HTML version.
Probabilistic Ancestral Sequences
and Multiple Alignments, in Proceedings of the 5^{th}
SWAT conference, Reykjavik, Iceland, July 1996. LNCS Springer-Verlag
pp. 380-391.
HTML version,
postscript version.
Teaching Mathematics Through the Internet: Web Pearls' Approach,
Invited talk at the 9th Open Math workshop, Talahassee, Nov 13, 1998,
(and at the Dept of Mathematics, NC State, April 23, 1999).
Slides.
Partial inverse heuristic for the approximate solution of
non-linear equations, to appear in the proceedings of CASC99.
HTML version,
Slides presented
as an invited talk at ECCAD99,
postscript version.
Vertex cover heuristic algorithm and lower bound. Automatic Web-based
server..
The Darwin Manual, coauthored with Mike Hallett,
HTML version,
postscript version.
Notes for the course Computer Algebra II: Heuristic Algorithms.
HTML version,
postscript version.
Optimal Scoring Matrices for Estimating Distances Between Aligned
Sequences. (sumitted), coauthored with Chantal Korostensky.
HTML version,
postscript version.
Using Insertion and Deletion Events for Improving Multiple Sequence
Alignments and Building the Corresponding Evolutionary Tree.
(submitted), coauthored with Chantal Korostensky and Ulrike Stege.
HTML version,
postscript version.
Using Traveling Salesman Problem Algorithms for Evolutionary Tree
Construction. (submitted) coauthored with Chantal Korostensky.
HTML version,
postscript version.
Near Optimal Multiple Sequence Alignments Using a Travelling Salesman
Problem Approach. to appear in SPIRE '99,
coauthored with Chantal Korostensky.
HTML version,
postscript version.
Evaluation measures of multiple sequence alignments.
Journal of Computational Biochemistry (to appear) (1999),
coauthored with Chantal Korostensky and Steve A. Benner.
HTML version,
postscript version.
Automatic program generation using a Computer Algebra
System: Efficiency and Correctness
ACAT2000, Fermilab, Batavia Il, Oct. 16, 2000
HTML version.
String matching problems from Bioinformatics
which still need better solutions
SPIRE 2002, Lisboa, September 13, 2002
Extended abstract.Slide presentation.
Analysis of the accuracy
of system mathematical functions.
A rather demanding test of numerical accuracy of most
transcendental functions. September 2002.
Bio-recipes
(Bioinformatics recipes) in Darwin.
Bio-recipes are a collection of Darwin example programs.
They show how to program in Darwin in order to solve standard
and research problems in Bioinformatics.
Computing Phylogenetic Trees Based on Mithchondrial DNA (Eve's Tree)
Joint 33rd Speedup and 19th PARS Workshop,
Pharmazentrum, Basel, March 20th, 2003
Slide presentation.
Repeating Time Test for U(0,1) Random Number Generators,
Electronic publication,
May, 2003,
Program and documentation.
Numerical Analysis, Computer Algebra and Bioinformatics:
Having Fun with Optimization,
SVG 2004, Stanford, January 10, 2004
Slide presentation.
The tPI (tRNA Pairing Index), a mathematical measure of repetition in
a (biological) sequence,
Proceedings of the World Computer Congress, IFIP, Aug 25, 2004,
Toulouse, France.
Full paper,bio-recipe.
Some old papers and conference slides can be found
here.
Some group pictures
Picture of the arrival of the first
scientific computer (and IBM 360-44) in Uruguay in 1968.
From left to right, Dr. Manuel Sadosky, Unidentified person behind
him, Gaston Gonnet, Cora Sadosky, Rafael Laguardia, Mrs. Laguardia,
Luis Osin and Jorge Vidart.
Picture of the participants of the Maple
retreat on Saturday, June 20th, 1998. Wild Echo Lodge, Port Stanton,
Sparrow Lake, Ontario.
Pictures of the Latin2000 conference in
Punta del Este, Uruguay, April 10-14, 2000.
Four authors of the LambertW paper,
G. Gonnet, R. Corless, D. Knuth and D. Jeffrey.
Waterloo, October 20, 2000.