networkx.generators.directed.gn_graph¶

gn_graph
(n, kernel=None, create_using=None, seed=None)[source]¶ Returns the growing network (GN) digraph with
n
nodes.The GN graph is built by adding nodes one at a time with a link to one previously added node. The target node for the link is chosen with probability based on degree. The default attachment kernel is a linear function of the degree of a node.
The graph is always a (directed) tree.
 Parameters
n (int) – The number of nodes for the generated graph.
kernel (function) – The attachment kernel.
create_using (NetworkX graph constructor, optional (default DiGraph)) – Graph type to create. If graph instance, then cleared before populated.
seed (integer, random_state, or None (default)) – Indicator of random number generation state. See Randomness.
Examples
To create the undirected GN graph, use the
to_directed()
method:>>> D = nx.gn_graph(10) # the GN graph >>> G = D.to_undirected() # the undirected version
To specify an attachment kernel, use the
kernel
keyword argument:>>> D = nx.gn_graph(10, kernel=lambda x: x ** 1.5) # A_k = k^1.5
References
 1
P. L. Krapivsky and S. Redner, Organization of Growing Random Networks, Phys. Rev. E, 63, 066123, 2001.