def n_edges_between(g, nbunch1, nbunch2):
"""Number of edges betwen nbunches.
This returns the edges that begin in nbunch1 and end in nbunch2.
This interpertation holds true for directed and undirected graphs.
If nbunch1==nbunch2 and the graph is undirected, returns **double
the number of edges**. Any edges with both ends in the
intersection of nbunch1 and nbunch2 will be included twice for
directed graphs.
Return value:
Set of all edges (tuples ``(n1, n2)``) between two sets of
nodes nbunch1 and nbunch2.
Complexity:
time: ``O(len(nbunch1))`` or ``O( min(len(nbunch1), len(nbunch2)) )``
For undirected graphs, nbunch1 and nbunch2 will be can be
switched for efficiency purposes.
nbunch2 (or nbunch1, if switched) MUST be sets or support
``O(1)`` ``__contains__`` in order to achieve this optimal
efficiency, otherwise complexity is
``O(len(nbunch1)*len(nbunch2))``
space: O(1)
See also:
n_edges_between for a version that returns only the
counts between two nbunches.
"""
import verkko.misc.testutil as testutil
testutil.warn_untested()
n = 0
# switch so nbunch1 is the smaller set.
if (isinstance(g, networkx.Graph) and not isinstance(g, networkx.DiGraph)
and len(nbunch1) > len(nbunch2)):
nbunch1, nbunch2 = nbunch2, nbunch1
for n1 in nbunch1:
for neighbor in g.adj[n1]: # iterate neighbors (or successors)
if neighbor in nbunch2:
n += 1
return n
def n_edges_between(g, nbunch1, nbunch2):
"""Number of edges betwen nbunches.
This returns the edges that begin in nbunch1 and end in nbunch2.
This interpertation holds true for directed and undirected graphs.
If nbunch1==nbunch2 and the graph is undirected, returns **double
the number of edges**. Any edges with both ends in the
intersection of nbunch1 and nbunch2 will be included twice for
directed graphs.
Return value:
Set of all edges (tuples ``(n1, n2)``) between two sets of
nodes nbunch1 and nbunch2.
Complexity:
time: ``O(len(nbunch1))`` or ``O( min(len(nbunch1), len(nbunch2)) )``
For undirected graphs, nbunch1 and nbunch2 will be can be
switched for efficiency purposes.
nbunch2 (or nbunch1, if switched) MUST be sets or support
``O(1)`` ``__contains__`` in order to achieve this optimal
efficiency, otherwise complexity is
``O(len(nbunch1)*len(nbunch2))``
space: O(1)
See also:
n_edges_between for a version that returns only the
counts between two nbunches.
"""
import verkko.misc.testutil as testutil ; testutil.warn_untested()
n = 0
# switch so nbunch1 is the smaller set.
if (isinstance(g, networkx.Graph) and not isinstance(g, networkx.DiGraph)
and len(nbunch1) > len(nbunch2) ):
nbunch1, nbunch2 = nbunch2, nbunch1
for n1 in nbunch1:
for neighbor in g.adj[n1]: # iterate neighbors (or successors)
if neighbor in nbunch2:
n += 1
return n
def edges_between(g, nbunch1, nbunch2):
"""List of edges between two node sets.
For all information on this function, see documentation on
``n_edges_between``.
Return value: list of tuples ``(node1, node2)``
List of edges between nbunch1 and nbunch2. For directed
graphs, tuples are (from, to).
"""
import verkko.misc.testutil as testutil ; testutil.warn_untested()
# switch so nbunch1 is the smaller set.
if (isinstance(g, networkx.Graph) and not isinstance(g, networkx.DiGraph)
and len(nbunch1) > len(nbunch2) ):
nbunch1, nbunch2 = nbunch2, nbunch1
edges = [ ]
for n1 in nbunch1:
for neighbor in g.adj[n1]: # iterate neighbors (or successors)
if neighbor in nbunch2:
edges.append((n1, neighbor))
return edges
def edges_between(g, nbunch1, nbunch2):
"""List of edges between two node sets.
For all information on this function, see documentation on
``n_edges_between``.
Return value: list of tuples ``(node1, node2)``
List of edges between nbunch1 and nbunch2. For directed
graphs, tuples are (from, to).
"""
import verkko.misc.testutil as testutil
testutil.warn_untested()
# switch so nbunch1 is the smaller set.
if (isinstance(g, networkx.Graph) and not isinstance(g, networkx.DiGraph)
and len(nbunch1) > len(nbunch2)):
nbunch1, nbunch2 = nbunch2, nbunch1
edges = []
for n1 in nbunch1:
for neighbor in g.adj[n1]: # iterate neighbors (or successors)
if neighbor in nbunch2:
edges.append((n1, neighbor))
return edges