def __call__(self, treegraph: UGraph):
GRAPH = self.stpg.graph
vertices = set(treegraph.vertices)
# Build the subgraph induced by the nodes in treegraph
subgraph = UWGraph()
for v in vertices:
for u in GRAPH.adjacent_to(v):
if u in vertices:
weigth = GRAPH.weight(v, u)
subgraph.add_edge(v, u, weight=weigth)
# Compute the Prim MST for the subgraph
mst = UGraph()
queue = PriorityQueue()
start = choice(tuple(vertices))
for next_node, weight in subgraph.edges[start].items():
queue.push(weight, (start, next_node))
while queue:
node_start, node_end = queue.pop()
if node_end not in mst:
mst.add_edge(node_start, node_end)
for next_node, weight in subgraph.edges[node_end].items():
queue.push(weight, (node_end, next_node))
return mst
def __call__(self, parent_a, parent_b):
assert isinstance(
parent_a, EdgeSet
), f'parent_a has to be EdgeSet type. Give was {type(parent_a)}'
assert isinstance(
parent_b, EdgeSet
), f'parent_b has to be EdgeSet type. Give was {type(parent_b)}'
stpg = self.stpg
terminals = set(stpg.terminals)
subgraph = UGraph()
for edge in parent_a:
u, v = edge
subgraph.add_edge(u, v)
for edge in parent_b:
u, v = edge
subgraph.add_edge(u, v)
done = set()
result = EdgeSet()
v = terminals.pop()
while terminals:
done.add(v)
adjacents = subgraph.adjacent_to(v, lazy=False)
u = sample(adjacents, k=1)[0]
if u not in done:
result.add(v, u)
terminals.discard(u)
v = u
return result
def test_is_steiner_tree(self):
stpg = self.stpg
chromosome = gen_random_kruskal(stpg)
tree = UGraph()
for edge in chromosome:
v, u = edge
tree.add_edge(v, u)
_, response = is_steiner_tree(tree, stpg)
self.assertTrue(response['all_terminals_in'])
self.assertFalse(response['has_cycle'])
self.assertTrue(response['all_edges_are_reliable'])
self.assertTrue(response['graph_is_connected'])
def test_edge_non_exist_in_stpg_instance(self):
filename = path.join("tests", "data", "test4.txt")
stpg = ReaderORLibrary().parser(filename)
tree = UGraph()
edges = [(1, 3), (3, 8), (8, 5), (5, 6), (8, 9)]
for edge in edges:
v, u = edge
tree.add_edge(v, u)
evaluator = EvaluateTreeGraph(stpg)
self.assertTrue(callable(evaluator))
with self.assertRaises(ValueError):
cost, __ = evaluator(tree)
def __call__(self):
GRAPH = self.stpg.graph
terminals = self.stpg.terminals.copy()
result = UGraph()
v = terminals.pop()
while terminals:
adjacents = GRAPH.adjacent_to(v, lazy=False)
u = sample(adjacents, k=1)[0]
if u not in result:
result.add_edge(v, u)
terminals.discard(u)
v = u
return result
def test_example_solution_two_components(self):
filename = path.join("tests", "data", "test4.txt")
stpg = ReaderORLibrary().parser(filename)
tree = UGraph()
edges = [(1, 3), (3, 8), (8, 5), (5, 6), (2, 4)]
for edge in edges:
v, u = edge
tree.add_edge(v, u)
evaluator = EvaluateTreeGraph(stpg)
self.assertTrue(callable(evaluator))
cost, nro_partition = evaluator(tree)
self.assertEqual(nro_partition, 2)
self.assertEqual(cost, (5 + 7 + 7 + 15 + 16))
def __call__(self, red: UGraph, blue: UGraph):
child = UGraph()
red_only = UGraph()
blue_only = UGraph()
for v, u in red.gen_undirect_edges():
if blue.has_edge(v, u):
child.add_edge(v, u)
else:
red_only.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
if not red.has_edge(v, u):
blue_only.add_edge(v, u)
common_nodes_red = set(red_only.vertices) & set(blue.vertices)
common_nodes_blue = set(blue_only.vertices) & set(red.vertices)
red_partitions = self.find_partitions(red_only, common_nodes_red)
blue_partitions = self.find_partitions(blue_only, common_nodes_blue)
queue = PriorityQueue()
for partition in red_partitions:
queue.push(partition.cost, partition)
for partition in blue_partitions:
queue.push(partition.cost, partition)
common_nodes = set(red.vertices) | set(blue.vertices)
dset = DisjointSets()
for v in common_nodes:
dset.make_set(v)
for v, u in child.gen_undirect_edges():
dset.union(v, u)
while queue:
partition = queue.pop()
if check_portals(partition.portal, dset):
# add edges
for v, u in partition:
child.add_edge(v, u)
# update dset
portals = iter(partition.portal)
p_last = next(portals)
for p in portals:
dset.union(p_last, p)
p_last = p
return child
def test_if_is_it_a_tree(self):
filename = path.join('datasets', 'ORLibrary', 'steinb15.txt')
stpg = ReaderORLibrary().parser(filename)
crossover = CrossoverKruskalRST(stpg)
parent_a = gen_random_walk(stpg)
parent_b = gen_random_walk(stpg)
offspring = crossover(parent_a, parent_b)
tree = UGraph()
for edge in offspring:
u, v = edge[0], edge[1]
tree.add_edge(u, v)
_, response = is_steiner_tree(tree, stpg)
self.assertTrue(response['all_terminals_in'])
self.assertFalse(response['has_cycle'])
self.assertTrue(response['all_edges_are_reliable'])
self.assertTrue(response['graph_is_connected'])
def test_penality_function(self):
filename = path.join("tests", "data", "test4.txt")
stpg = ReaderORLibrary().parser(filename)
tree = UGraph()
edges = [(1, 3), (3, 8), (8, 5), (5, 6), (2, 4)]
for edge in edges:
v, u = edge
tree.add_edge(v, u)
evaluator = EvaluateTreeGraph(stpg,
penality_function=lambda nro:
(nro - 1) * 100)
self.assertTrue(callable(evaluator))
cost, nro_partition = evaluator(tree)
self.assertEqual(nro_partition, 2)
self.assertEqual(cost, (5 + 7 + 7 + 15 + 16 + 100))
def __call__(self, treegraph: UGraph):
terminals = self.terminals
result = UGraph()
for v, u in treegraph.gen_undirect_edges():
result.add_edge(v, u)
leaves = deque([
v for v in result.vertices
if (v not in terminals) and (result.degree(v) == 1)
])
while leaves:
v = leaves.pop()
for w in result.adjacent_to(v):
if (w not in terminals) and (result.degree(w) == 2):
leaves.appendleft(w)
result.remove_node(v)
return result
def __call__(self, treegraph: UGraph):
GRAPH = self.stpg.graph
disjointset = DisjointSets()
result = UGraph()
for v in treegraph.vertices:
disjointset.make_set(v)
# remove edge
edges = [edge for edge in treegraph.gen_undirect_edges()]
index = randint(0, len(edges))
for i, edge in enumerate(edges):
if index != i:
result.add_edge(*edge)
disjointset.union(*edge)
candidates = list()
components = disjointset.get_disjoint_sets()
lesser_idx = min(components, key=lambda key: len(components[key]))
keys = components.keys() - set([lesser_idx])
# replace edge
lesser_component = components[lesser_idx]
for key in keys:
other_component = components[key]
for v in lesser_component:
for w in GRAPH.adjacent_to(v):
if w in other_component:
candidates.append((v, w))
shuffle(candidates)
while candidates:
v, w = candidates.pop()
if disjointset.find(v) != disjointset.find(w):
result.add_edge(v, w)
disjointset.union(v, w)
break
return result
def __call__(self, red: UGraph, blue: UGraph):
assert isinstance(
red, UGraph), f'red parent must be UGraph. Given {type(red)}'
assert isinstance(
blue, UGraph), f'blue parent must be UGraph. Given {type(blue)}'
union_g = UGraph()
for v, u in red.gen_undirect_edges():
union_g.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
union_g.add_edge(v, u)
terminals = self.terminals.copy()
done = set()
result = UGraph()
candidates_edges = set()
vi = terminals.pop()
done.add(vi)
for u in union_g.adjacent_to(vi):
candidates_edges.add((vi, u))
while candidates_edges and terminals:
edge = sample(candidates_edges, k=1)[0]
v, w = edge
if w not in done:
done.add(w)
result.add_edge(v, w)
terminals.discard(w)
for u in union_g.adjacent_to(w):
if u not in done:
candidates_edges.add((w, u))
candidates_edges.discard((v, w))
return result
def __call__(self, red: UGraph, blue: UGraph):
assert isinstance(
red, UGraph), f'red parent must be UGraph. Given {type(red)}'
assert isinstance(
blue, UGraph), f'blue parent must be UGraph. Given {type(blue)}'
terminals = self.terminals.copy()
union_g = UGraph()
for v, u in red.gen_undirect_edges():
union_g.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
union_g.add_edge(v, u)
done = set()
result = UGraph()
v = terminals.pop()
while terminals:
done.add(v)
adjacents = union_g.adjacent_to(v, lazy=False)
u = sample(adjacents, k=1)[0]
if u not in done:
result.add_edge(v, u)
terminals.discard(u)
v = u
return result
def __call__(self, red: UGraph, blue: UGraph):
f_weight = lambda v, u: self.stpg.graph.weight(v, u)
union_g = UGraph()
for v, u in red.gen_undirect_edges():
union_g.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
union_g.add_edge(v, u)
queue = PriorityQueue()
start = choice(tuple(self.stpg.terminals))
for u in union_g.adjacent_to(start):
queue.push(f_weight(start, u), (start, u))
result = UGraph()
while queue:
start, end = queue.pop()
if end not in result:
result.add_edge(start, end)
for w in union_g.adjacent_to(end):
queue.push(f_weight(end, w), (end, w))
return result
def __call__(self, red, blue):
assert isinstance(
red, UGraph), f'red parent must be UGraph. Given {type(red)}'
assert isinstance(
blue, UGraph), f'blue parent must be UGraph. Given {type(blue)}'
done = DisjointSets()
union_g = UGraph()
for v, u in red.gen_undirect_edges():
union_g.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
union_g.add_edge(v, u)
for v in union_g.vertices:
done.make_set(v)
all_edges = set()
for edge in union_g.gen_undirect_edges():
all_edges.add(edge)
result = UGraph()
while all_edges and len(done.get_disjoint_sets()) > 1:
edge = sample(all_edges, k=1)[0]
v, u = edge[0], edge[1]
if done.find(v) != done.find(u):
result.add_edge(v, u)
done.union(v, u)
all_edges.remove(edge)
return result
def __call__(self, parent_a, parent_b):
assert isinstance(
parent_a, EdgeSet
), f'parent_a has to be EdgeSet type. Give was {type(parent_a)}'
assert isinstance(
parent_b, EdgeSet
), f'parent_b has to be EdgeSet type. Give was {type(parent_b)}'
stpg = self.stpg
terminals = set(stpg.terminals)
done = set()
result = EdgeSet()
subgraph = UGraph()
for edge in parent_a:
u, v = edge
subgraph.add_edge(u, v)
for edge in parent_b:
u, v = edge
subgraph.add_edge(u, v)
vi = terminals.pop()
done.add(vi)
candidates_edges = set()
for u in subgraph.adjacent_to(vi):
candidates_edges.add((vi, u))
while candidates_edges and terminals:
edge = sample(candidates_edges, k=1)[0]
v, w = edge
if w not in done:
done.add(w)
result.add(v, w)
terminals.discard(w)
for u in subgraph.adjacent_to(w):
if u not in done: candidates_edges.add((w, u))
candidates_edges.discard((v, w))
return result
def test_exchange_edges(self):
filename = path.join('tests', 'data', 'test3.txt')
stpg = ReaderORLibrary().parser(filename)
red = UGraph()
edges = [(1, 3), (3, 8), (8, 5), (5, 6)]
for edge in edges:
red.add_edge(edge[0], edge[1])
blue = UGraph()
edges = [(1, 3), (3, 8), (3, 7), (7, 4), (4, 6)]
for edge in edges:
blue.add_edge(edge[0], edge[1])
crossover = PXTree(stpg)
child = crossover(red, blue)
_, response = is_steiner_tree(child, stpg)
self.assertTrue(response['all_terminals_in'])
self.assertFalse(response['has_cycle'])
self.assertTrue(response['all_edges_are_reliable'])
self.assertTrue(response['graph_is_connected'])
self.assertTrue(response['all_leaves_are_terminals'])
def test_simpliest(self):
stpg = self.stpg
mutate = MutationReplaceByRandomEdge(stpg)
after = gen_random_prim(stpg)
self.assertIsInstance(after, EdgeSet)
before = mutate(after)
self.assertIsInstance(before, EdgeSet)
tree = UGraph()
for edge in before:
v, u = edge
tree.add_edge(v, u)
_, response = is_steiner_tree(tree, stpg)
self.assertTrue(response['all_terminals_in'])
self.assertFalse(response['has_cycle'])
self.assertTrue(response['all_edges_are_reliable'])
self.assertTrue(response['graph_is_connected'])
def __call__(self):
result = UGraph()
terminals = self.stpg.terminals.copy()
GRAPH = self.stpg.graph
edges = set() # or is it better a list?
vi = sample(range(1, self.stpg.nro_nodes + 1), k=1)[0]
terminals.discard(vi)
for w in GRAPH.adjacent_to(vi):
edges.add((vi, w))
while terminals and edges:
edge = sample(edges, k=1)[0] # need to ensure randomness
v, w = edge
if w not in result:
terminals.discard(w)
result.add_edge(v, w)
for u in GRAPH.adjacent_to(w):
if u not in result:
edges.add((w, u))
edges.remove(edge) # to remove from a list it can take O(n)
return result
def __call__(self, red: UGraph, blue: UGraph):
g_union = UGraph()
for v, u in red.gen_undirect_edges():
g_union.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
g_union.add_edge(v, u)
p_queue = PriorityQueue()
vertices = list(g_union.vertices)
v = choice(vertices)
for u in g_union.adjacent_to(v):
weight = self.f_weight(v, u)
p_queue.push(weight, (v, u))
g_child = UGraph()
done = set()
done.add(v)
while len(p_queue):
v, u = p_queue.pop()
if u not in done:
g_child.add_edge(v, u)
done.add(u)
for w in g_union.adjacent_to(u):
if w not in done:
p_queue.push(self.f_weight(u, w), (u, w))
terminals = self.STPG.terminals
prunne_leaves = deque([
v for v in g_child.vertices
if ((g_child.degree(v) == 1) and (v not in terminals))
])
while prunne_leaves:
v = prunne_leaves.pop()
prev = g_child.adjacent_to(v, lazy=False)
g_child.remove_node(v)
for w in prev:
if g_child.degree(w) == 1 and w not in terminals:
prunne_leaves.appendleft(w)
return g_child
def __call__(self, red: UGraph, blue: UGraph):
child = UGraph()
red_only = UGraph()
blue_only = UGraph()
_vertices = set()
for v, u in red.gen_undirect_edges():
if blue.has_edge(v, u):
child.add_edge(v, u)
_vertices.add(v)
_vertices.add(u)
else:
red_only.add_edge(v, u)
for v, u in blue.gen_undirect_edges():
if not red.has_edge(v, u):
blue_only.add_edge(v, u)
common_nodes_red = set(red_only.vertices) & set(blue.vertices)
common_nodes_blue = set(blue_only.vertices) & set(red.vertices)
red_partitions = self.find_partitions(red_only, common_nodes_red)
blue_partitions = self.find_partitions(blue_only, common_nodes_blue)
_vertices.update(common_nodes_red | common_nodes_blue)
disjoint = DisjointSets()
for v in _vertices:
disjoint.make_set(v)
for v, u in child.gen_undirect_edges():
disjoint.union(v, u)
red_dict = _dict_matches_from(red_partitions, disjoint)
blue_dict = _dict_matches_from(blue_partitions, disjoint)
matches = red_dict.keys() & blue_dict.keys()
while matches:
child, red_dict, blue_dict, disjoint = select_partition_and_union(
child, red_dict, blue_dict, disjoint, matches)
red_dict = _dict_matches_from(red_dict.values(), disjoint)
blue_dict = _dict_matches_from(blue_dict.values(), disjoint)
matches = red_dict.keys() & blue_dict.keys()
red_child = UGraph()
blue_child = UGraph()
for v, u in child.gen_undirect_edges():
red_child.add_edge(v, u)
blue_child.add_edge(v, u)
for partition in red_dict.values():
for v, u in partition:
red_child.add_edge(v, u)
for partition in blue_dict.values():
for v, u in partition:
blue_child.add_edge(v, u)
return red_child, blue_child