min_indegree()#
relationalai.std.graphs.Compute
#min_indegree() -> Expression
Compute the minimum indegree of all nodes in a graph.
In a directed graph, the indegree of a node is the number of edges that point to the node.
For an undirected graph, .min_indegree()
is an alias of .min_degree()
.
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 minimum indegree of the graph as an integer value.
Example#
Use .min_indegree()
to compute the minimum indegree of a graph.
You access the .min_indegree()
method from a Graph
object’s
.compute
attribute:
#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 minimum indegree of the graph.
with model.query() as select:
min_indegree = graph.compute.min_indegree()
response = select(min_indegree)
print(response.results)
# Output:
# v
# 0 1
In undirected graphs, .min_indegree()
is the same as .min_degree()
.