def add_edges_from(self, ebunch, attr_dict=None, **attr):
# set up attribute dict
if attr_dict is None:
attr_dict = attr
else:
try:
attr_dict.update(attr)
except AttributeError:
raise MiniNXError(\
"The attr_dict argument must be a dict.")
# process ebunch
for e in ebunch:
ne = len(e)
if ne == 3:
u, v, dd = e
assert hasattr(dd, "update")
elif ne == 2:
u, v = e
dd = {}
else:
raise MiniNXError(\
"Edge tuple %s must be a 2-tuple or 3-tuple."%(e,))
if u not in self.succ:
self.succ[u] = self.adjlist_dict_factory()
self.pred[u] = self.adjlist_dict_factory()
self.node[u] = {}
if v not in self.succ:
self.succ[v] = self.adjlist_dict_factory()
self.pred[v] = self.adjlist_dict_factory()
self.node[v] = {}
datadict = self.adj[u].get(v, self.edge_attr_dict_factory())
datadict.update(attr_dict)
datadict.update(dd)
self.succ[u][v] = datadict
self.pred[v][u] = datadict
def remove_edge(self, u, v, key=None):
try:
d = self.adj[u][v]
except (KeyError):
raise MiniNXError(
"The edge %s-%s is not in the graph." % (u, v))
# remove the edge with specified data
if key is None:
d.popitem()
else:
try:
del d[key]
except (KeyError):
raise MiniNXError(
"The edge %s-%s with key %s is not in the graph." % (u, v, key))
if len(d) == 0:
# remove the key entries if last edge
del self.succ[u][v]
del self.pred[v][u]
def remove_node(self, n):
try:
nbrs = self.succ[n]
del self.node[n]
except KeyError: # MiniNXError if n not in self
raise MiniNXError("The node %s is not in the digraph." % (n, ))
for u in nbrs:
del self.pred[u][n] # remove all edges n-u in digraph
del self.succ[n] # remove node from succ
for u in self.pred[n]:
del self.succ[u][n] # remove all edges n-u in digraph
del self.pred[n] # remove node from pred
def add_node(self, n, attr_dict=None, **attr):
# set up attribute dict
if attr_dict is None:
attr_dict = attr
else:
try:
attr_dict.update(attr)
except AttributeError:
raise MiniNXError(\
"The attr_dict argument must be a dictionary.")
if n not in self.succ:
self.succ[n] = self.adjlist_dict_factory()
self.pred[n] = self.adjlist_dict_factory()
self.node[n] = attr_dict
else: # update attr even if node already exists
self.node[n].update(attr_dict)
def add_edge(self, u, v, key=None, attr_dict=None, **attr):
# set up attribute dict
if attr_dict is None:
attr_dict = attr
else:
try:
attr_dict.update(attr)
except AttributeError:
raise MiniNXError(
"The attr_dict argument must be a dictionary.")
# add nodes
if u not in self.succ:
self.succ[u] = self.adjlist_dict_factory()
self.pred[u] = self.adjlist_dict_factory()
self.node[u] = {}
if v not in self.succ:
self.succ[v] = self.adjlist_dict_factory()
self.pred[v] = self.adjlist_dict_factory()
self.node[v] = {}
if v in self.succ[u]:
keydict = self.adj[u][v]
if key is None:
# find a unique integer key
# other methods might be better here?
key = len(keydict)
while key in keydict:
key += 1
datadict = keydict.get(key, self.edge_key_dict_factory())
datadict.update(attr_dict)
keydict[key] = datadict
else:
# selfloops work this way without special treatment
if key is None:
key = 0
datadict = self.edge_attr_dict_factory()
datadict.update(attr_dict)
keydict = self.edge_key_dict_factory()
keydict[key] = datadict
self.succ[u][v] = keydict
self.pred[v][u] = keydict
def add_edge(self, u, v, attr_dict=None, **attr):
# set up attribute dict
if attr_dict is None:
attr_dict = attr
else:
try:
attr_dict.update(attr)
except AttributeError:
raise MiniNXError(\
"The attr_dict argument must be a dictionary.")
# add nodes
if u not in self.succ:
self.succ[u] = self.adjlist_dict_factory()
self.pred[u] = self.adjlist_dict_factory()
self.node[u] = {}
if v not in self.succ:
self.succ[v] = self.adjlist_dict_factory()
self.pred[v] = self.adjlist_dict_factory()
self.node[v] = {}
# add the edge
datadict = self.adj[u].get(v, self.edge_attr_dict_factory())
datadict.update(attr_dict)
self.succ[u][v] = datadict
self.pred[v][u] = datadict
def predecessors(self, n):
try:
return iter(self.pred[n])
except KeyError:
raise MiniNXError("The node %s is not in the digraph." % (n, ))
def remove_edge(self, u, v):
try:
del self.succ[u][v]
del self.pred[v][u]
except KeyError:
raise MiniNXError("The edge %s-%s not in graph." % (u, v))