A bidirected generalisation of network matrices
نویسندگان
چکیده
We provide a new class of matrices, called binet matrices (denoted by B), which guarantee half-integral vertices for the polytope P = fx : l x u; a Bx bg. They furnish a direct generalisation of totally unimodular network matrices and arise from the node-edge incidence matrices of bidirected graphs in the same way as the network matrices do from directed graphs. We develop the necessary theory and examples, point to existing polynomial algorithms which can be deployed to solve LP and IP problems defined over P , prove that B has strong Chvátal rank 1 and discuss the recognition problem.
منابع مشابه
On the representability of totally unimodular matrices on bidirected graphs
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