14 citations · 16 across the 8 of their papers we have counts for
3 papers · 1 filter
Totally equimodular matrices: decomposition and triangulation
Patrick Chervet, Roland Grappe, Mathieu Vallée
Totally equimodular matrices generalize totally unimodular matrices and arise in the context of box-total dual integral polyhedra. This work further explores the parallels between…
Contractions in perfect graph
Alexandre Dupont-Bouillard, Pierre Fouilhoux, Roland Grappe +1
In this paper, we characterize the class of {\em contraction perfect} graphs which are the graphs that remain perfect after the contraction of any edge set. We prove that a graph i…
Drawing disconnected graphs on the Klein bottle
Laurent Beaudou, Antoine Gerbaud, Roland Grappe +1
We prove that two disjoint graphs must always be drawn separately on the Klein bottle, in order to minimize the crossing number of the whole drawing.