def edges(self, source=None, target=None):
if source is None and target is None:
for e in self.graph.edges():
yield e
#TODO: still think it might be a good idea to
# yield reverse_edge(e) here, since if you
# really wanted distinct edges, you could
# always get them from any call to edges
# by just filtering distinct edges
elif source is not None and target is not None:
for e in self.graph.edges(source=source, target=target):
yield e
if source != target:
for e in self.graph.edges(source=target, target=source):
yield reverse_edge(e)
elif source is not None:
for e in self.graph.edges(source=source):
yield e
if source != target:
for e in self.graph.edges(target=source):
yield reverse_edge(e)
else:
for e in self.graph.edges(target=target):
yield e
if source != target:
for e in self.graph.edges(source=target):
yield reverse_edge(e)
def path(self, source, target):
if source == target:
return
starting_source, starting_target = source, target
vertices_seen = set([source, target])
s_iter = self.__parent_edge.get(source)
t_iter = self.__parent_edge.get(target)
s_path, t_path = [], []
while s_iter != t_iter:
if s_iter is not None:
s_path.append(s_iter)
source = other_vertex(s_iter, source)
if source in vertices_seen:
break
vertices_seen.add(source)
s_iter = self.__parent_edge.get(source)
if t_iter is not None:
t_path.append(t_iter)
target = other_vertex(t_iter, target)
if target in vertices_seen:
break
vertices_seen.add(target)
t_iter = self.__parent_edge.get(target)
if s_iter is None and t_iter is None:
raise NoPathExistsError
if source == starting_target or source == target:
for edge in s_path:
yield reverse_edge(edge)
if target == starting_source or source == target:
for edge in reversed(t_path):
yield edge
def reroot(self, v):
current_node = v
deferred_edges = list()
while self.__parent_edge[current_node] is not None:
parent_edge = self.__parent_edge[current_node]
self.split(current_node)
deferred_edges.append(reverse_edge(parent_edge))
current_node = other_vertex(parent_edge, current_node)
for edge in deferred_edges:
self.add_edge(*edge)
def __call__(self, **kwargs):
if self.tree_type == "from_source":
v = kwargs["target"]
else:
v = kwargs["source"]
# TODO: simplify this mess
edges = []
while self.tree.get(v) is not None:
edges.append(self.tree[v])
v = other_vertex(self.tree[v], v)
if self.tree_type == "from_source":
for e in reversed(edges):
yield e
else:
for e in edges:
yield reverse_edge(e)
def edges(self, source = None, target = None):
for e in self.graph.edges(source=target, target=source):
yield reverse_edge(e)
