Algorithms for a Bit-Vector Encoding of Trees

  • Kaoutar GhaziEmail author
  • Laurent Beaudou
  • Olivier Raynaud
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 866)


A bit-vector encoding is a well known method for representing hierarchies (i.e. partially ordered sets). This encoding corresponds to an embedding of a given hierarchy into a Boolean lattice whose dimension is the encoding’s size. Computing an optimal bit-vector encoding, which size is called the 2-dimension, is an \(\mathcal {N}\mathcal {P}\)-hard problem. Hence, many algorithms were designed to provide good bit-vector encoding. In this paper, we study tree hierarchies. We analyse previous algorithms for their bit-vector encoding then we point out their common strategy that led us to design a new algorithm improving all the previous ones.


Partially ordered set Tree Bit-vector encoding 2-dimension Algorithms 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Kaoutar Ghazi
    • 1
    Email author
  • Laurent Beaudou
    • 2
  • Olivier Raynaud
    • 2
  1. 1.GREYC, Caen Normandie UniversityCaenFrance
  2. 2.LIMOS, Clermont Auvergne UniversityClermont-FerrandFrance

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