add()#

relationalai.std.graphs.Edge
add(from_: Producer, to: Producer, **kwargs: Any) -> EdgeInstance

Adds edges to the graph from objects produced by from_ to objects produced by to. Edge properties may be passed as keyword arguments to **kwargs. Objects produced by from_ and to are automatically added to the graph’s nodes. Must be called in a rule or query context.

Parameters#

NameTypeDescription
from_ProducerThe node at the start of the edge.
toProducerThe node at the end of the edge.
**kwargsAnyKeyword arguments to set the edge’s properties.

Returns#

An EdgeInstance object.

Example#

Use Edge.add() to add edges to the graph:

import relationalai as rai
from relationalai.std.graphs import Graph

# Create a model with 'Person' and 'Transaction' types.
model = rai.Model("transactions")
Person = model.Type("Person")
Transaction = model.Type("Transaction")

# Add some people and transactions to the model.
with model.rule():
    alice = Person.add(name="Alice")
    bob = Person.add(name="Bob")
    Transaction.add(sender=bob, receiver=alice, amount=100.0)

# Create a directed graph.
graph = Graph(model)

# Add transactions to the graph as edges.
# The 'weight' parameter sets the weight property of each edge.
with model.rule():
    transaction = Transaction()
    graph.Edge.add(
        from_=transaction.sender,
        to=transaction.receiver,
        weight=transaction.amount
    )

# Query the edges in the graph.
with model.query() as select:
    edge = graph.Edge()
    response = select(edge.from_.name, edge.to.name, edge.weight)

print(response.results)
# Output:
#   name  name2      v
# 0  Bob  Alice  100.0

See Also#