Algorithms and Complexity Group
  • People
  • Research
  • Courses
  • Talks
  • Jobs
  • Contact

FraSMT - A tool for computing the fractional hypertree width of hypergraphs

Bounded fractional hypertree width (fhtw) is the most general known structural property that guarantees polynomial-time solvability of the constraint satisfaction problem. Bounded fhtw generalizes other structural properties like bounded induced width and bounded hypertree width.

FraSMT is the first practical algorithm for computing the fhtw and its associated structural decomposition. FraSMT is based on an efficient encoding of the decomposition problem to SMT (SAT modulo Theory) with Linear Arithmetic as implemented in the SMT solver Z3. The encoding is further strengthened by preprocessing and symmetry breaking methods.

Downloads

The fraSMT tool can be downloaded from this GitHub page.

Benchmark instances can be downloaded from this Zendodo.org page.

Team

Markus Hecher, Johannes Fichte, Neha Lodha, Stefan Szeider

Publications

1 result
2018
[1]An SMT Approach to Fractional Hypertree Width
Johannes K. Fichte, Markus Hecher, Neha Lodha, Stefan Szeider
Proceedings of CP 2018, the 24rd International Conference on Principles and Practice of Constraint Programming (John N. Hooker, ed.), volume 11008 of Lecture Notes in Computer Science, pages 109–127, 2018, Springer Verlag.
[bibtex] [pdf] [doi]

News

  • Martin Nöllenburg: promotion to Full Professor

    Martin Nöllenburg: promotion to Full Professor

    2020-12-17
    By December 1st, 2020, our colleague Martin Nöllenburg has been promoted to Full Professor for Graph and Geometric Algorithms.  Martin has …Read More »
  • Martin Kronegger wins the Best Teaching Award 2020

    Martin Kronegger wins the Best Teaching Award 2020

    2020-10-23
    Congratulations to Martin Kronegger who received a Best Teaching Award 2020 from TU Wien. The Algorithms and Complexity group is …Read More »
  • Welcome to our Feodor Lynen Fellow Dr. Manuel Sorge

    Welcome to our Feodor Lynen Fellow Dr. Manuel Sorge

    2020-10-12
    On October 1, 2020, Dr. Manuel Sorge has joined the Algorithms and Complexity group with a prestigious Feodor Lynen postdoc …Read More »
  • TU Wien students excel at the 2020 Graph Drawing Contest

    TU Wien students excel at the 2020 Graph Drawing Contest

    2020-10-01
    The 27th annual Graph Drawing Contest, held (virtually) in conjunction with the 28th International Symposium on Graph Drawing and Network …Read More »
  • Best Paper Award at CP’2020

    Best Paper Award at CP’2020

    2020-09-11
    Tomáš Peitl and Stefan Szeider won the Best Paper Award at the main track of CP'2020, the 26th International Conference on Principles …Read More »

News archive

All news for 2015, 2016, 2017, 2018 and 2019.
TU Wien Informatics
Offenlegung (§25 MedienG) Inhaber der Website ist das Institut für Logic and Computation an der Technischen Universität Wien, 1040 Wien. Die TU Wien distanziert sich von den Inhalten aller extern gelinkten Seiten und übernimmt diesbezüglich keine Haftung. – Disclaimer – Datenschutzerklärung
Log in requires cookies.