Assertion: graph's ordering | /r/HasProperty | topological
Facets:
Source sentences:
text: Conversely, every directed acyclic graph has at least one topological ordering.
text: Every directed acyclic graph has a topological ordering, an ordering of the vertices such that the starting endpoint of every edge occurs earlier in the ordering than the ending endpoint of the edge.
text: This follows because all directed acyclic graphs have a topological ordering, i.e. there is at least one way to put the vertices in an order such that all edges point in the same direction along that order.
text: A directed graph is acyclic if and only if it has a topological ordering.
text: The existence of such an ordering can be used to characterize DAGs: a directed graph is a DAG if and only if it has a topological ordering.
text: A graph that has a topological ordering cannot have any cycles, because the edge into the earliest vertex of a cycle would have to be oriented the wrong way.