--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/planemo/lib/python3.7/site-packages/networkx/algorithms/isolate.py	Fri Jul 31 00:32:28 2020 -0400
@@ -0,0 +1,115 @@
+# -*- encoding: utf-8 -*-
+#    Copyright 2015 NetworkX developers.
+#    Copyright (C) 2004-2019 by
+#    Aric Hagberg <hagberg@lanl.gov>
+#    Dan Schult <dschult@colgate.edu>
+#    Pieter Swart <swart@lanl.gov>
+#    All rights reserved.
+#    BSD license.
+"""
+Functions for identifying isolate (degree zero) nodes.
+"""
+import networkx as nx
+
+__author__ = """\n""".join(['Drew Conway <drew.conway@nyu.edu>',
+                            'Aric Hagberg <hagberg@lanl.gov>'])
+
+__all__ = ['is_isolate', 'isolates', 'number_of_isolates']
+
+
+def is_isolate(G, n):
+    """Determines whether a node is an isolate.
+
+    An *isolate* is a node with no neighbors (that is, with degree
+    zero). For directed graphs, this means no in-neighbors and no
+    out-neighbors.
+
+    Parameters
+    ----------
+    G : NetworkX graph
+
+    n : node
+        A node in `G`.
+
+    Returns
+    -------
+    is_isolate : bool
+       True if and only if `n` has no neighbors.
+
+    Examples
+    --------
+    >>> G=nx.Graph()
+    >>> G.add_edge(1,2)
+    >>> G.add_node(3)
+    >>> nx.is_isolate(G,2)
+    False
+    >>> nx.is_isolate(G,3)
+    True
+    """
+    return G.degree(n) == 0
+
+
+def isolates(G):
+    """Iterator over isolates in the graph.
+
+    An *isolate* is a node with no neighbors (that is, with degree
+    zero). For directed graphs, this means no in-neighbors and no
+    out-neighbors.
+
+    Parameters
+    ----------
+    G : NetworkX graph
+
+    Returns
+    -------
+    iterator
+        An iterator over the isolates of `G`.
+
+    Examples
+    --------
+    To get a list of all isolates of a graph, use the :class:`list`
+    constructor::
+
+        >>> G = nx.Graph()
+        >>> G.add_edge(1, 2)
+        >>> G.add_node(3)
+        >>> list(nx.isolates(G))
+        [3]
+
+    To remove all isolates in the graph, first create a list of the
+    isolates, then use :meth:`Graph.remove_nodes_from`::
+
+        >>> G.remove_nodes_from(list(nx.isolates(G)))
+        >>> list(G)
+        [1, 2]
+
+    For digraphs, isolates have zero in-degree and zero out_degre::
+
+        >>> G = nx.DiGraph([(0, 1), (1, 2)])
+        >>> G.add_node(3)
+        >>> list(nx.isolates(G))
+        [3]
+
+    """
+    return (n for n, d in G.degree() if d == 0)
+
+
+def number_of_isolates(G):
+    """Returns the number of isolates in the graph.
+
+    An *isolate* is a node with no neighbors (that is, with degree
+    zero). For directed graphs, this means no in-neighbors and no
+    out-neighbors.
+
+    Parameters
+    ----------
+    G : NetworkX graph
+
+    Returns
+    -------
+    int
+        The number of degree zero nodes in the graph `G`.
+
+    """
+    # TODO This can be parallelized.
+    return sum(1 for v in isolates(G))