condensation¶

condensation(G, scc=None)[source]¶

Returns the condensation of G.

The condensation of G is the graph with each of the strongly connected components contracted into a single node.

Parameters:

G : NetworkX DiGraph

A directed graph.

scc: list or generator (optional, default=None)

Strongly connected components. If provided, the elements in \(scc\) must partition the nodes in \(G\). If not provided, it will be calculated as scc=nx.strongly_connected_components(G).

Returns:

C : NetworkX DiGraph

The condensation graph C of G. The node labels are integers corresponding to the index of the component in the list of strongly connected components of G. C has a graph attribute named ‘mapping’ with a dictionary mapping the original nodes to the nodes in C to which they belong. Each node in C also has a node attribute ‘members’ with the list of original nodes in G that form the SCC that the node in C represents.

Raises:

NetworkXNotImplemented: If G is not directed

Notes

After contracting all strongly connected components to a single node, the resulting graph is a directed acyclic graph.