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arXiv 0904.3436math.CO
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用有向超图计算热带多面体的顶点

Computing the vertices of tropical polyhedra using directed hypergraphs

Xavier Allamigeon, Stephane Gaubert, Eric Goubault

摘要:

我们建立了一个热带多面体的顶点的特征定义为相交的许多半空间。我们表明,一个点是一个顶点,当且仅当,一个有向超图,构造从次微分的积极约束在这一点上,承认一个唯一的强连通组件是最大的可达性关系(所有其他强连通组件都可以访问它)。这个属性几乎可以在线性时间内检查。这使我们能够开发一个热带模拟经典的双重描述方法,计算一个最小的内部表示(顶点)的多面体定义外部(半空间或超平面)。我们提供了理论上的最坏情况下的复杂性界限,并报告使用库TPLib进行了广泛的实验测试,表明这种方法优于其他现有的方法。

英文摘要:

We establish a characterization of the vertices of a tropical polyhedron defined as the intersection of finitely many half-spaces. We show that a point is a vertex if, and only if, a directed hypergraph, constructed from the subdifferentials of the active constraints at this point, admits a unique strongly connected component that is maximal with respect to the reachability relation (all the other strongly connected components have access to it). This property can be checked in almost linear-time. This allows us to develop a tropical analogue of the classical double description method, which computes a minimal internal representation (in terms of vertices) of a polyhedron defined externally (by half-spaces or hyperplanes). We provide theoretical worst case complexity bounds and report extensive experimental tests performed using the library TPLib, showing that this method outperforms the other existing approaches.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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