def test_number_strongly_connected_big(self):
G = retworkx.PyDiGraph()
for i in range(100000):
node = G.add_node(i)
G.add_child(node, str(i), {})
self.assertEqual(len(retworkx.strongly_connected_components(G)),
200000)
def test_number_strongly_connected(self):
G = retworkx.PyDiGraph()
node_a = G.add_node(1)
node_b = G.add_child(node_a, 2, {})
node_c = G.add_node(3)
self.assertEqual(retworkx.strongly_connected_components(G),
[[node_c], [node_b], [node_a]])
def test_stongly_connected_no_linear(self):
G = retworkx.PyDiGraph()
G.add_nodes_from(list(range(8)))
G.add_edges_from_no_data([
(0, 1),
(1, 2),
(1, 7),
(2, 3),
(2, 6),
(3, 4),
(4, 2),
(4, 5),
(6, 3),
(6, 5),
(7, 0),
(7, 6),
])
expected = [[5], [2, 3, 4, 6], [0, 1, 7]]
components = retworkx.strongly_connected_components(G)
self.assertEqual(components, expected)
import os
import tempfile
from typing import Sized
from PIL import Image
import pydot
import retworkx as rx
import igraph as ig
import numpy as np
G: rx.PyDiGraph = rx.directed_gnm_random_graph(1000, 2000, None)
components: list = rx.strongly_connected_components(G)
largest_component: Sized = max(components, key=len)
H: rx.PyGraph = G.subgraph(largest_component)
# have to fix pydot error
"""
dot = pydot.graph_from_dot_data(G.to_dot())[0]
with tempfile.TemporaryDirectory() as tmpdirname:
tmp_path = os.path.join(tmpdirname, 'dag.png')
dot.write_png(tmp_path)
image = Image.open(tmp_path)
os.remove(tmp_path)
image
"""
n1: np.ndarray = rx.digraph_adjacency_matrix(G, None)
g: ig.Graph = ig.Graph.Weighted_Adjacency(n1.tolist())
ig.plot(g)
def largest_connected_component(self):
"""Return a set of qubits in the largest connected component."""
return max(rx.strongly_connected_components(self.graph), key=len)
def time_strongly_connected_components(self):
retworkx.strongly_connected_components(self.graph)
