Note

This documents the development version of NetworkX. Documentation for the current release can be found here.

networkx.algorithms.centrality.trophic_levels

trophic_levels(G, weight='weight')[source]

Compute the trophic levels of nodes.

The trophic level of a node \(i\) is

\[s_i = 1 + \frac{1}{k^{in}_i} \sum_{j} a_{ij} s_j\]

where \(k^{in}_i\) is the in-degree of i

\[k^{in}_i = \sum_{j} a_{ij}\]

and nodes with \(k^{in}_i = 0\) have \(s_i = 1\) by convention.

These are calculated using the method outlined in Levine [1].

Parameters
GDiGraph

A directed networkx graph

Returns
nodesdict

Dictionary of nodes with trophic level as the vale.

References

1

Stephen Levine (1980) J. theor. Biol. 83, 195-207