DOCS: Fix internal links to other functions in isomorphvf2 (networkx#…

…6706)

* DOCS: Fix internal links to other functions in isomorphvf2

networkx/algorithms/isomorphism/isomorphvf2.py

@@ -5,7 +5,9 @@
 
 An implementation of VF2 algorithm for graph isomorphism testing.
 
-The simplest interface to use this module is to call networkx.is_isomorphic().
+The simplest interface to use this module is to call the
+:func:`is_isomorphic <networkx.algorithms.isomorphism.is_isomorphic>`
+function.
 
 Introduction
 ------------
@@ -21,9 +23,10 @@
 as the logical AND of the two functions.
 
 To include a semantic check, the (Di)GraphMatcher class should be
-subclassed, and the semantic_feasibility() function should be
-redefined.  By default, the semantic feasibility function always
-returns True.  The effect of this is that semantics are not
+subclassed, and the
+:meth:`semantic_feasibility <networkx.algorithms.isomorphism.GraphMatcher.semantic_feasibility>`
+function should be redefined.  By default, the semantic feasibility function always
+returns ``True``.  The effect of this is that semantics are not
 considered in the matching of G1 and G2.
 
 Examples
@@ -65,43 +68,44 @@
 Graph theory literature can be ambiguous about the meaning of the
 above statement, and we seek to clarify it now.
 
-In the VF2 literature, a mapping M is said to be a graph-subgraph
-isomorphism iff M is an isomorphism between G2 and a subgraph of G1.
-Thus, to say that G1 and G2 are graph-subgraph isomorphic is to say
-that a subgraph of G1 is isomorphic to G2.
+In the VF2 literature, a mapping `M` is said to be a graph-subgraph
+isomorphism iff `M` is an isomorphism between `G2` and a subgraph of `G1`.
+Thus, to say that `G1` and `G2` are graph-subgraph isomorphic is to say
+that a subgraph of `G1` is isomorphic to `G2`.
 
-Other literature uses the phrase 'subgraph isomorphic' as in 'G1 does
-not have a subgraph isomorphic to G2'.  Another use is as an in adverb
-for isomorphic.  Thus, to say that G1 and G2 are subgraph isomorphic
-is to say that a subgraph of G1 is isomorphic to G2.
+Other literature uses the phrase 'subgraph isomorphic' as in '`G1` does
+not have a subgraph isomorphic to `G2`'.  Another use is as an in adverb
+for isomorphic.  Thus, to say that `G1` and `G2` are subgraph isomorphic
+is to say that a subgraph of `G1` is isomorphic to `G2`.
 
 Finally, the term 'subgraph' can have multiple meanings. In this
 context, 'subgraph' always means a 'node-induced subgraph'. Edge-induced
 subgraph isomorphisms are not directly supported, but one should be
-able to perform the check by making use of nx.line_graph(). For
+able to perform the check by making use of
+:func:`line_graph <networkx.generators.line.line_graph>`. For
 subgraphs which are not induced, the term 'monomorphism' is preferred
 over 'isomorphism'.
 
-Let G=(N,E) be a graph with a set of nodes N and set of edges E.
+Let ``G = (N, E)`` be a graph with a set of nodes `N` and set of edges `E`.
 
-If G'=(N',E') is a subgraph, then:
-    N' is a subset of N
-    E' is a subset of E
+If ``G' = (N', E')`` is a subgraph, then:
+    `N'` is a subset of `N` and
+    `E'` is a subset of `E`.
 
-If G'=(N',E') is a node-induced subgraph, then:
-    N' is a subset of N
-    E' is the subset of edges in E relating nodes in N'
+If ``G' = (N', E')`` is a node-induced subgraph, then:
+    `N'` is a subset of `N` and
+    `E'` is the subset of edges in `E` relating nodes in `N'`.
 
-If G'=(N',E') is an edge-induced subgraph, then:
-    N' is the subset of nodes in N related by edges in E'
-    E' is a subset of E
+If `G' = (N', E')` is an edge-induced subgraph, then:
+    `N'` is the subset of nodes in `N` related by edges in `E'` and
+    `E'` is a subset of `E`.
 
-If G'=(N',E') is a monomorphism, then:
-    N' is a subset of N
-    E' is a subset of the set of edges in E relating nodes in N'
+If `G' = (N', E')` is a monomorphism, then:
+    `N'` is a subset of `N` and
+    `E'` is a subset of the set of edges in `E` relating nodes in `N'`.
 
-Note that if G' is a node-induced subgraph of G, then it is always a
-subgraph monomorphism of G, but the opposite is not always true, as a
+Note that if `G'` is a node-induced subgraph of `G`, then it is always a
+subgraph monomorphism of `G`, but the opposite is not always true, as a
 monomorphism can have fewer edges.
 
 References
@@ -120,7 +124,8 @@
 
 See Also
 --------
-syntactic_feasibility(), semantic_feasibility()
+:meth:`semantic_feasibility <networkx.algorithms.isomorphism.GraphMatcher.semantic_feasibility>`
+:meth:`syntactic_feasibility <networkx.algorithms.isomorphism.GraphMatcher.syntactic_feasibility>`
 
 Notes
 -----