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This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.

# dfs_preorder_nodes¶

dfs_preorder_nodes(G, source=None)[source]

Produce nodes in a depth-first-search pre-ordering starting from source.

Parameters : G : NetworkX graph source : node, optional Specify starting node for depth-first search and return edges in the component reachable from source. nodes: generator A generator of nodes in a depth-first-search pre-ordering.

Notes

Based on http://www.ics.uci.edu/~eppstein/PADS/DFS.py by D. Eppstein, July 2004.

If a source is not specified then a source is chosen arbitrarily and repeatedly until all components in the graph are searched.

Examples

>>> G = nx.Graph()