gammoid造句

• The dual of a transversal matroid is a strict gammoid and vice versa.
• Every uniform matroid is a paving matroid, a transversal matroid and a strict gammoid.
• Thus, a gammoid is a restriction of a strict gammoid, to a subset of its elements.
• Thus, a gammoid is a restriction of a strict gammoid, to a subset of its elements.
• In this graph, every vertex corresponds to an element of the matroid, showing that the uniform matroid is a strict gammoid.
• A "'strict gammoid "'is a gammoid in which the set T of destination vertices consists of every vertex in G.
• A "'strict gammoid "'is a gammoid in which the set T of destination vertices consists of every vertex in G.
• To see, conversely, that every transversal matroid is dual to a strict gammoid, find a subfamily of the sets defining the matroid such that the subfamily has a system of distinct representatives and defines the same matroid.
• Then the sets N _ v formed as above for each representative element v are exactly the sets defining the original transversal matroid, so the strict gammoid formed by this graph and by the set of representative elements is dual to the given transversal matroid.
• Alternatively, the same uniform matroid U { } ^ r _ n may be represented as a gammoid on a smaller graph, with only n vertices, by choosing a subset S of r vertices and connecting each of the chosen vertices to every other vertex in the graph.