A good leaf of hypergraph H is an edge L whose intersections with all other edges form a totally ordered set. It follows that L must have a free vertex. In the graph setting, a good leaf is an edge containing a vertex of degree one. The notion of a good leaf was introduced by X. Zheng in her Ph.D. thesis (2004).
i1 : R = QQ[a..g]; |
i2 : H = hyperGraph {b*c*d*e, a*b*c*d, c*d*f, d*g, e*f*g};
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i3 : getGoodLeaf(H)
o3 = {a, b, c, d}
o3 : List
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i4 : edges(H)
o4 = {{a, b, c, d}, {b, c, d, e}, {c, d, f}, {d, g}, {e, f, g}}
o4 : List
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i5 : getGoodLeafIndex(H) o5 = 0 |
The object getGoodLeafIndex is a method function.