526
个编辑
更改
→Hypergraphs 超图
Because the edges of ordinary graphs can only have two vertices (one at each end), the column of an incidence matrix for graphs can only have two non-zero entries. By contrast, a hypergraph can have multiple vertices assigned to one edge; thus, a general matrix of non-negative integers describes a hypergraph.
Because the edges of ordinary graphs can only have two vertices (one at each end), the column of an incidence matrix for graphs can only have two non-zero entries. By contrast, a hypergraph can have multiple vertices assigned to one edge; thus, a general matrix of non-negative integers describes a hypergraph.
因为一般图的边只能有两个顶点（每端一个），所以图的关联矩阵列只能有两个非零项。相比之下，超图却可以有多个顶点指定给一条边。因此，一般的非负整数矩阵才能用来描述超图。
==Incidence structures 关联结构==
==Incidence structures 关联结构==