def build_join_tree(self, triangulatedGraph):
# The Triangulated Graph is really a graph of cliques.
cliques = triangulatedGraph.cliques
# We start by creating a forest of trees, one for each clique.
forest = [JoinTree(clique) for clique in cliques]
sepsetHeap = self.create_sepset_priority_queue(cliques)
# Join n - 1 sepsets together forming (hopefully) a single tree.
for n in range(len(forest) - 1):
while sepsetHeap:
sepset = heapq.heappop(sepsetHeap)
# Find out which tree each clique is from
joinTreeX = GraphUtilities.getTree(forest, sepset.cliqueX)
joinTreeY = GraphUtilities.getTree(forest, sepset.cliqueY)
if not joinTreeX == joinTreeY:
# If the cliques are on different trees, then join to make a larger one.
joinTreeX.merge(sepset, joinTreeY)
forest.remove(joinTreeY)
break
if len(forest) > 1:
raise BadTreeStructure(
"Inference on a forest of Junction Trees is not yet supported")
else:
tree = forest[0]
tree.init_clique_potentials(self.bnet.nodes)
return tree
def build_join_tree (self, triangulatedGraph):
# The Triangulated Graph is really a graph of cliques.
cliques = triangulatedGraph.cliques
# We start by creating a forest of trees, one for each clique.
forest = [JoinTree(clique) for clique in cliques]
sepsetHeap = self.create_sepset_priority_queue(cliques)
# Join n - 1 sepsets together forming (hopefully) a single tree.
for n in range(len(forest) - 1):
while sepsetHeap:
sepset = heapq.heappop(sepsetHeap)
# Find out which tree each clique is from
joinTreeX = GraphUtilities.getTree(forest, sepset.cliqueX)
joinTreeY = GraphUtilities.getTree(forest, sepset.cliqueY)
if not joinTreeX == joinTreeY:
# If the cliques are on different trees, then join to make a larger one.
joinTreeX.merge(sepset, joinTreeY)
forest.remove(joinTreeY)
break
if len(forest) > 1:
raise BadTreeStructure("Inference on a forest of Junction Trees is not yet supported")
else:
tree = forest[0]
tree.init_clique_potentials(self.bnet.nodes)
return tree
