Flows in Oriented Matroids
نویسندگان
چکیده
Recently Hochstättler and Nešetřil [3] introduced the flow lattice of an oriented matroid as generalization of the lattice of all integer flows of a digraph or more general a regular matroid. This lattice is defined as the integer hull of the characteristic vectors of signed circuits. We describe the structure and the dimension of the flow lattice for uniform and rank 3 oriented matroids and construct a basis of signed circuits. Furthermore, we analyze the behaviour of the dimension of the flow lattice under the 2-sum of oriented matroids and present some quesions based on computational results on catalogs of oriented matroids.
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