Serge Torres
LIP - Éns de Lyon
46, allée d'Italie
F-69364 Lyon Cedex 07
Phone: +33 (0) 4 72 72 86 48 or +33 (0) 04 37 28 76 45

Welcome to my scanty Home Page!
Hi! I'm a research engineer with the LIP laboratory at Éns de Lyon. I share my worktime between the laboratory IT management team (MI-LIP) and the AriC research team.

My main research topic is function approximation by polynomials and rational fractions. More precisely, I apply linear programming tools (exact and/or parametric linear programming) to the search of optimal “constrained” (e. g. bit size and/or pattern) polynomial coefficients.

My favorite gears for this kind of work are still PIP and GLPK. ISL and SCIP are promizing alternatives. I also extensively use Sollya, as mostly everyone in the team. MPFR is an undispensable tool of the trade to all high-precision numerics craftsmen. SAGE is the current game in town as for mathematical software system, at least for those who want to stand on the free side.

In the context of the development of an implémentation of the SLZ2 algorithm in Sage, I am developping interfaces between Sage and C, on the one hand, and Sollya, on the other hand. This work-in-progress is openly available from svn checkout

PERL, Bash and Python are also put to use for gluing tools together.

Some of the code I've put up together can be found under the MEPLIB project (badly out of sync too!).

For IT management duties, my MI-LIP buddies are Simon Delamare, Jean-Christophe Mignot, Joris Picot and Dominique Ponsard. We run a mostly Debian shop here.

1Sylvain Chevillard, Mioara Joldeş, Christoph Lauter.

2 See: D.  Stehlé, V.  Lefèvre, P.  Zimmerman. Worst Cases abd Lattice Reduction, in: Proceedings of the 16th IEEE Symposium on Computer Arithmetic, 2003, Santiago de Compostela, Spain, pp.142–147.


Sometime in 2018…
Publication of the second edition of the Handbook of Floating-Point Arithmetic.

End 2017
Official retirement.

S. Torres.
Tools for the Design of Reliable and Efficient Functions Evaluation Libraries
Phd Thesis under the supervision of Jean-Michel Muller and Nicolas Brisebarre and evaluated by an examining committee comprised of:
F. de Dinechin, C. Lauter, J.-M. Muller, S.Torres.
On Ziv's Rounding Test.
in: ACM Transactions on Mathematical Software, Vol. 39(4), 2013.

J.-M. Muller, N. Brisebarre, F. de Dinechin, C.-P. Jeannerod, V. Lefèvre, G. Melquiond N. Revol, D. Stehlé, S.Torres.
Handbook of Floating-Point Arithmetic.,
Birkhäuser Boston, 2010.

N. Brisebarre, S. Chevillard, M. Ercegovac, J.-M. Muller, S. Torres.
An efficient Method for Evaluating Polynomial and Rational Function Approximations,
in: Application-specific Systems, Architectures and Processors, IEEE, 2008, p. 245–250.

N. Brisebarre, J.-M. Muller, A. Tisserand, S. Torres.
Hardware Operators for Function Evaluation Using Sparse-Coefficient Polynomials,
in: Electronic Letters, Vol. 42, Issue: 25, 2006, p. 1441–1442.