Module petgraph::visit

Graph traits and graph traversals.

The Into- Traits

Graph traits like IntoNeighbors create iterators and use the same pattern that IntoIterator does: the trait takes a reference to a graph, and produces an iterator. These traits are quite composable, but with the limitation that they only use shared references to graphs.

Graph Traversal

Dfs, Bfs, DfsPostOrder and Topo are basic visitors and they use “walker” methods: the visitors don’t hold the graph as borrowed during traversal, only for the .next() call on the walker. They can be converted to iterators through the Walker trait.

There is also the callback based traversal depth_first_search.

Other Graph Traits

The traits are rather loosely coupled at the moment (which is intentional, but will develop a bit), and there are traits missing that could be added.

Not much is needed to be able to use the visitors on a graph. A graph needs to define GraphBase, IntoNeighbors and Visitable as a minimum.

Structs

Bfs	A breadth first search (BFS) of a graph.
Dfs	Visit nodes of a graph in a depth-first-search (DFS) emitting nodes in preorder (when they are first discovered).
DfsPostOrder	Visit nodes in a depth-first-search (DFS) emitting nodes in postorder (each node after all its descendants have been emitted).
EdgeFiltered	An edge-filtering graph adaptor.
EdgeFilteredEdges	A filtered edges iterator.
EdgeFilteredNeighbors	A filtered neighbors iterator.
EdgeFilteredNeighborsDirected	A filtered neighbors-directed iterator.
NodeFiltered	A node-filtering graph adaptor.
NodeFilteredEdgeReferences	A filtered edges iterator.
NodeFilteredEdges	A filtered edges iterator.
NodeFilteredNeighbors	A filtered neighbors iterator.
NodeFilteredNodes	A filtered node references iterator.
Reversed	An edge-reversing graph adaptor.
ReversedEdgeReference	A reversed edge reference
ReversedEdgeReferences	A reversed edge references iterator.
ReversedEdges	A reversed edges iterator.
Time	Strictly monotonically increasing event time for a depth first search.
Topo	A topological order traversal for a graph.
WalkerIter	A walker and its context wrapped into an iterator.

Enums

Control	Control flow for depth_first_search callbacks.
DfsEvent	A depth first search (DFS) visitor event.

Traits

ControlFlow	Control flow for callbacks.
Data	Define associated data for nodes and edges
EdgeRef	An edge reference.
FilterEdge	A graph filter for edges
FilterNode	A graph filter for nodes.
GetAdjacencyMatrix	Create or access the adjacency matrix of a graph.
GraphBase	Base graph trait: defines the associated node identifier and edge identifier types.
GraphProp	Edge kind property (directed or undirected edges)
GraphRef	A copyable reference to a graph.
IntoEdgeReferences	Access to the sequence of the graph’s edges
IntoEdges	Access to the edges of each node.
IntoEdgesDirected	Access to all edges of each node, in the specified direction.
IntoNeighbors	Access to the neighbors of each node
IntoNeighborsDirected	Access to the neighbors of each node, through incoming or outgoing edges.
IntoNodeIdentifiers	Access to the sequence of the graph’s NodeIds.
IntoNodeReferences	Access to the sequence of the graph’s nodes
NodeCompactIndexable	The graph’s NodeIds map to indices, in a range without holes.
NodeCount	A graph with a known node count.
NodeIndexable	The graph’s NodeIds map to indices
NodeRef	A node reference.
VisitMap	A mapping for storing the visited status for NodeId N.
Visitable	A graph that can create a map that tracks the visited status of its nodes.
Walker	A walker is a traversal state, but where part of the traversal information is supplied manually to each next call.

Functions

depth_first_search

A recursive depth first search.