PyReason Infer Edges

In this tutorial, we will look at how to run PyReason with infer edges. infer edges is a parameter in the Rule Class.

Note

Find the full, excecutable code here

The following graph represents a network of airports and connections.

Graph

First, we create the graph in Networkx. This graph has airports and flight connections.

import networkx as nx

# Create a directed graph
G = nx.DiGraph()

# Add nodes with attributes
nodes = [
    ("Amsterdam_Airport_Schiphol", {"Amsterdam_Airport_Schiphol": 1}),
    ("Riga_International_Airport", {"Riga_International_Airport": 1}),
    ("Chișinău_International_Airport", {"Chișinău_International_Airport": 1}),
    ("Yali", {"Yali": 1}),
    ("Düsseldorf_Airport", {"Düsseldorf_Airport": 1}),
    ("Pobedilovo_Airport", {"Pobedilovo_Airport": 1}),
    ("Dubrovnik_Airport", {"Dubrovnik_Airport": 1}),
    ("Hévíz-Balaton_Airport", {"Hévíz-Balaton_Airport": 1}),
    ("Athens_International_Airport", {"Athens_International_Airport": 1}),
    ("Vnukovo_International_Airport", {"Vnukovo_International_Airport": 1})
]

G.add_nodes_from(nodes)

# Add edges with 'isConnectedTo' attribute
edges = [
    ("Pobedilovo_Airport", "Vnukovo_International_Airport", {"isConnectedTo": 1}),
    ("Vnukovo_International_Airport", "Hévíz-Balaton_Airport", {"isConnectedTo": 1}),
    ("Düsseldorf_Airport", "Dubrovnik_Airport", {"isConnectedTo": 1}),
    ("Dubrovnik_Airport", "Athens_International_Airport", {"isConnectedTo": 1}),
    ("Riga_International_Airport", "Amsterdam_Airport_Schiphol", {"isConnectedTo": 1}),
    ("Riga_International_Airport", "Düsseldorf_Airport", {"isConnectedTo": 1}),
    ("Chișinău_International_Airport", "Riga_International_Airport", {"isConnectedTo": 1}),
    ("Amsterdam_Airport_Schiphol", "Yali", {"isConnectedTo": 1})
]

G.add_edges_from(edges)

We can also load the graph from a GraphML file

We then initialize and load the graph using the following code:

import pyreason as pr

pr.reset()
pr.reset_rules()
# Modify pyreason settings to make verbose and to save the rule trace to a file
pr.settings.verbose = True
pr.settings.atom_trace = True
pr.settings.memory_profile = False
pr.settings.canonical = True
pr.settings.inconsistency_check = False
pr.settings.static_graph_facts = False
pr.settings.output_to_file = False
pr.settings.store_interpretation_changes = True
pr.settings.save_graph_attributes_to_trace = True
# Load all the files into pyreason
pr.load_graph(G)

Rules

Next, add the Rule and set infer_edges to True

pr.add_rule(pr.Rule('isConnectedTo(A, Y) <-1  isConnectedTo(Y, B), Amsterdam_Airport_Schiphol(B), Vnukovo_International_Airport(A)', 'connected_rule_1', infer_edges=True))

This will should connect exactly one new relationship from A to Y. The Rule states that if there is a connection from Y to B, then infer an edge from A to Y.

• B is Amsterdam Airport Schiphol

• Y is Riga_International_Airport

• A is Vnukovo_International_Airport

Therefore the output of the graph after running 1 timestep should be a new connection [1,1] between Vnukovo_International_Airport (A) to Riga_International_Airport (Y).

Facts

This example does not havea any facts. All initial conditions are set when the graph is created

Running PyReason

Run the program for 1 timesteps.

# Run the program for one timesteps to see the diffusion take place

interpretation = pr.reason(timesteps=1)

Expected output

After running the python file, the expected output is:

The expected output after running will list at timestep 0 the inital connections and timestep 1 the added connection due to the infer_edges parameter.

Timestep: 0
Timestep: 1

Converged at time: 1
Fixed Point iterations: 2
TIMESTEP - 0
                                        component isConnectedTo
0                 (Amsterdam_Airport_Schiphol, Yali)    [1.0, 1.0]
1  (Riga_International_Airport, Amsterdam_Airport...    [1.0, 1.0]
2   (Riga_International_Airport, Düsseldorf_Airport)    [1.0, 1.0]
3  (Chișinău_International_Airport, Riga_Internat...    [1.0, 1.0]
4            (Düsseldorf_Airport, Dubrovnik_Airport)    [1.0, 1.0]
5  (Pobedilovo_Airport, Vnukovo_International_Air...    [1.0, 1.0]
6  (Dubrovnik_Airport, Athens_International_Airport)    [1.0, 1.0]
7  (Vnukovo_International_Airport, Hévíz-Balaton_...    [1.0, 1.0]

TIMESTEP - 1
                                        component isConnectedTo
0  (Vnukovo_International_Airport, Riga_Internati...    [1.0, 1.0]

The graph after running shows a new connection from Vnukovo_International_Airport to Riga_International_Airport, because during the reasoning process an edges between them was infered.