Computations with finite closure systems and implications

  • Marcel Wild
Session 2B: Database
Part of the Lecture Notes in Computer Science book series (LNCS, volume 959)


Closure systems C ⊂ 2Mon a finite set M arise in many areas of discrete mathematics. They are conveniently encoded by either the family Irr(C) of meet irreducible closed sets, or by implicational bases Σ. We significantly improve six (partly little known) algorithms in order to settle the problems (a),(b),... (g) listed below. In particular, the algorithm LINCLOSURE, which is well known in relational database theory, is enhanced. It appears as a subroutine in three of our algorithms. Applications in database theory, matroid theory and algebra will be pointed out.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Marcel Wild
    • 1
  1. 1.Fachbereich MathematikTHDDarmstadtGermany

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