Polyhedral combinatorics | Matrices

Birkhoff polytope

The Birkhoff polytope Bn (also called the assignment polytope, the polytope of doubly stochastic matrices, or the perfect matching polytope of the complete bipartite graph ) is the convex polytope in RN (where N = n2) whose points are the doubly stochastic matrices, i.e., the n × n matrices whose entries are non-negative real numbers and whose rows and columns each add up to 1. It is named after Garrett Birkhoff. (Wikipedia).

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Ehrhart polynomial | Ford–Fulkerson algorithm | Graph (discrete mathematics) | Matching polytope | Convex hull | Perfect matching | Contingency table | Neighborly polytope | Stable matching polytope | Dénes Kőnig | Isohedral figure | Regular graph | Symmetric group | Bayesian statistics | Birkhoff algorithm | Facet (geometry) | Regular polytope | Integral polytope | Doubly stochastic matrix | Complete bipartite graph | Convex polytope | Bipartite graph | Permutohedron | Complete graph | Young tableau | Real number | Cayley graph | Extreme point | Linear inequality | Matching (graph theory) | Matrix (mathematics) | Dual polyhedron | Ernst Steinitz | Garrett Birkhoff