oriented matroid

例句：

1. 1. The oriented matroid is amathematical concept that describes the structure of agraph with respect to its orientation.
   有向的马特罗是一个数学概念，它描述了具有方向性的图的结构。
2. 2. In combinatorial optimization, the orientedmatroid is used to model the problemof finding the minimum spanning tree ina weighted graph.
   在组合优化中，有向马特罗被用来建模寻找加权图中最小生成树的问题。
3. 3.The oriented matroid is a generalization of the directed matroid, whichis a type of hypergraph.
   有向马特罗是定向马特罗的一般化，而定向马特罗是一种超图类型。