Cubic time recognition of cocircuit graphs of uniform oriented matroids

نویسندگان

  • Stefan Felsner
  • Ricardo Gómez Aiza
  • Kolja B. Knauer
  • Juan José Montellano-Ballesteros
  • Ricardo Strausz
چکیده

We present an algorithm which takes a graph as input and decides in cubic time if the graph is the cocircuit graph of a uniform oriented matroid. In the affirmative case the algorithm returns the set of signed cocircuits of the oriented matroid. This improves an algorithm proposed by Babson, Finschi and Fukuda. Moreover we strengthen a result of Montellano-Ballesteros and Strausz about crabbed connectivity of cocircuit graphs of uniform oriented matroids.

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عنوان ژورنال:
  • Eur. J. Comb.

دوره 32  شماره 

صفحات  -

تاریخ انتشار 2011