def extract_kbest_forest(self, forest, kbest = 1):
"extract the forest created by the kbest final parses"
marked_edges = set()
done_nodes = set([forest.root])
edge_stack = sum([item.last_edges for item in self.hypothesis_cache[forest.root][0:kbest]], [])
#print [str(edge.rule) for edge in edge_stack]
#print "Marked edges"
while edge_stack:
#print edge_stack
edge, vecj = edge_stack.pop()
marked_edges.add(edge.position_id)
for sub, j in izip(edge.subs, vecj):
#if sub in done_nodes: continue
#done_nodes.add(sub)
item = self.hypothesis_cache[sub][j]
#print item.full_derivation
edge_stack.extend(item.last_edges)
def node_pruning(node):
return False
def edge_pruning(edge):
return edge.position_id not in marked_edges
return general_prune(forest, node_pruning, edge_pruning)
def extract_pruned_forest(self, forest, extract = 1):
"extract the forest created by cube pruning"
def node_pruning(node):
if self.hypothesis_cache.has_key(node):
return False
return True
def edge_pruning(edge):
#print "need edge %s %s" %(edge,edge.position_id)
node = edge.head
hypvec = self.hypothesis_cache[node]
for i, item in enumerate(hypvec):
#print "Last edge is %s %s" % (item.last_edge,item.last_edge.position_id)
if edge.position_id in [e.position_id for e in item.last_edges] :
return False
if i == extract: break
return True
return general_prune(forest, node_pruning, edge_pruning)
