avg_degree()#
relationalai.std.graphs.Compute
#avg_degree() -> Expression
Get the average degree of all nodes the graph. For an undirected graph, the degree of a node is the number of neighbors it has in the graph. In a directed graph, the degree of a node is the sum of its indegree and outdegree. Must be called in a rule or query context.
Supported Graph Types#
Graph Type | Supported | Notes |
---|---|---|
Directed | Yes | |
Undirected | Yes | |
Weighted | Yes | Weights are ignored. |
Unweighted | Yes |
Returns#
Returns an Expression object that produces the average degree of the graph as a floating-point value.
Example#
Use .avg_degree()
to compute the average degree of a graph:
#import relationalai as rai
from relationalai.std.graphs import Graph
# Create a model named "socialNetwork" with a Person type
model = rai.Model("socialNetwork")
Person = model.Type("Person")
# Add some people to the graph and connect them with a 'friends' property.
with model.rule():
alice = Person.add(name="Alice")
bob = Person.add(name="Bob")
carol = Person.add(name="Carol")
alice.friends.extend([bob, carol])
bob.friends.add(alice)
carol.friends.add(alice)
# Create an undirected graph with Person nodes and edges between friends.
# This graph has two edges: one between Alice and Bob and one between Alice and Carol.
graph = Graph(model, undirected=True)
graph.Node.extend(Person)
graph.Edge.extend(Person.friends)
# Compute the average degree of the graph.
with model.query() as select:
avg_degree = graph.compute.avg_degree()
response = select(avg_degree)
print(response.results)
# Output:
# v
# 0 1.333333
In directed graphs, the degree of a node is the sum of its indegree and outdegree:
## Create a directed graph with Person nodes and edges between friends.
# Note that graphs are directed by default.
# This graph has four edges: two between Alice and Bob and two between Alice and Carol.
directed_graph = Graph(model)
directed_graph.Node.extend(Person)
directed_graph.Edge.extend(Person.friends)
# Compute the average degree of the directed graph.
with model.query() as select:
avg_degree = directed_graph.compute.avg_degree()
response = select(avg_degree)
print(response.results)
# Output:
# v
# 0 2.666667