Gilles VILLARD    Directeur de recherche CNRS/INS2I
AriC project-team

Laboratoire LIP   [CNRS  ENSL  INRIA  UCBL  U. Lyon ]
  46, Allée d'Italie F69364   Lyon   Cedex 07

MILyon postdoctoral positions 2022-2024, deadline for applications: January 4th, 2022.

PUBLICATIONS    Detailed list / co-authors.


  • V. Neiger, B. Salvy, É. Schost, G. Villard. Faster modular composition, arXiv:2110.08354, 2021.
  • P. Karpman, C. Pernet, H. Signargout, G. Villard. Computing the characteristic polynomial of generic Toeplitz-like and Hankel-like Matrices. ISSAC'21, Virtual Event, Russian Federation, 2021, pdf/doi.
  • C.-P. Jeannerod, V. Neiger, G. Villard. Fast computation of approximant bases in canonical form. Journal of Symbolic Computation, 98:192-224, 2020, pdf/doi.
  • G. Villard. On computing the resultant of generic bivariate polynomials. ISSAC'18, New York, USA, 2018, pdf/doi, and maple worksheets.
  • J.-G. Dumas, E.Kaltofen, G.Villard, L. Zhi. Polynomial time interactive proofs for linear algebra with exponential matrix dimensions and scalars given by polynomial time circuits. ISSAC'17, Kaiserslautern, Germany, 2017, pdf/doi.
  • C.-P. Jeannerod, V. Neiger, É. Schost, G. Villard. Computing minimal interpolation bases, J. of Symbolic Computation, 83:272-314, 2017, pdf/doi.
  • Saruchi, I. Morel, D. Stehlé, G. Villard. LLL reducing with the most significant bits. ISSAC'14, Kobe, Japan, 2014, pdf/doi.
  • X.-W. Chang, D. Stehlé, G. Villard. Perturbation analysis of the QR factor R in the context of LLL lattice basis reduction, Mathematics of Computation, 81(279):1487-1511, 2012, pdf/doi.
  • G. Villard. Recent progress in linear algebra and lattice basis reduction. ISSAC'11, San Jose, California, 2011, invited, pdf/doi.
  • A. Novocin, D. Stehlé, G. Villard. An LLL-reduction algorithm with quasi-linear time complexity, STOC, San Jose, California, 2011, pdf/doi.
  • E. Kaltofen, G. Villard. On the complexity of computing determinants. Computational Complexity, 13:91-130, 2005, pdf/doi.


  • Extended precision floating-point benchmarks.
  • Hplll software library home page,  GitHub repository.
  • LinBox joint CNRS/NSF project LinBox Team GitHub (
  • The Givaro page, a C++ library for computer algebra.
  • TO SEE

    International Linear Algebra Society         GDR CNRS Informatique Mathématique - GT Arithmétique - GT Calcul Formel

            TeresaFest 2021, Symbolic and Numerical Algorithms in Algebraic Geometry, in honour of Teresa Krick, 13-15 Dec. 2021, Buenos Aires/virtual.
            FOCS 2021, 62nd Annual IEEE Symposium on Foundations of Computer Science, February 7-10, 2022, Boulder, Colorado.
            JNCF 2022, Journées Nationales de Calcul Formel, CIRM, Luminy, 28 février- 4 mars 2022.
            STACS 2022, 39th International Symposium on Theoretical Aspects of Computer Science, March 15-18, 2022, Marseille.
            C2 2022, Journées Codage et Cryptographie, Hendaye, 10-15 avril 2022.
            ISSAC 2022, 47th International Symposium on Symbolic and Algebraic Computation, July 4-7, 2022, Lille.
            ICALP 2022, 50th International Colloquium on Automata, Languages and Programming, July 4-8, 2022, Paris.