def random_path(graph):
"""
Constructs a randomly-generated valid hyperpath.
Parameters
------------
graph : Hypergraph
Returns
----------
path : Hyperpath
A randomly generated hyperpath.
"""
def random_path_edges(node):
edges = []
if node.edges:
edge = random.sample(node.edges, 1)
edges.append(edge[0])
for t in edge[0].tail:
edges += random_path_edges(t)
return edges
edges = random_path_edges(graph.root)
return pydecode.Path(graph, edges)
def path(self):
if self._status != pulp.LpStatusOptimal:
raise Exception("No optimal solution.")
else:
path_edges = [
edge for edge in self.hypergraph.edges
if pulp.value(self.edge_vars[edge.id]) == 1.0
]
return pydecode.Path(self.hypergraph, path_edges)
def outside_paths(graph, vertex):
if vertex.id == graph.root.id: return [None]
def has_vertex(path):
for edge in path.edges:
for tail in edge.tail:
if vertex.id == tail.id:
return True
return False
paths = [pydecode.Path(graph, list(edges))
for edges in _paths(graph.root, vertex)]
paths = [path for path in paths if has_vertex(path)]
return paths
def all_paths(graph):
"""
Constructs all possible hyperpaths through a hypergraph (for testing).
Parameters
------------
graph : Hypergraph
Returns
----------
paths : list of hyperpaths
All hyperpaths in the graph.
"""
paths = [pydecode.Path(graph, list(edges))
for edges in _paths(graph.root)]
return paths
def inside_paths(graph, vertex):
paths = [pydecode.Path(graph, list(edges))
for edges in _paths(vertex)]
return paths