Make a pass over parametric graph section..

Some type-checking corrections were made and some bugs found from this fixed.

Author: rocky

pymathics/graph/__init__.py

@@ -60,7 +60,7 @@
     VertexList,
 )
 
-from pymathics.graph.centralities import(
+from pymathics.graph.centralities import (
     BetweennessCentrality,
     ClosenessCentrality,
     DegreeCentrality,
@@ -86,7 +86,6 @@
     CompleteGraph,
     CompleteKaryTree,
     CycleGraph,
-    FullRAryTree,
     GraphAtlas,
     HknHararyGraph,
     HmnHararyGraph,
@@ -144,7 +143,6 @@
     "FindShortestPath",
     "FindSpanningTree",
     "FindVertexCut",
-    "FullRAryTree",
     "Graph",
     "GraphAtlas",
     "GraphAtom",

pymathics/graph/base.py

@@ -86,7 +86,7 @@ def graph_helper(
     root: Optional[int] = None,
     *args,
     **kwargs,
-) -> Optional[Callable]:
+) -> Optional["Graph"]:
     should_digraph = can_digraph and has_directed_option(options)
     try:
         G = (
@@ -97,7 +97,11 @@ def graph_helper(
     except MemoryError:
         evaluation.message("Graph", "mem", evaluation)
         return None
-    if graph_layout and not options["System`GraphLayout"].get_string_value():
+    if (
+        graph_layout and not options["System`GraphLayout"].get_string_value()
+        if "System`GraphLayout" in options
+        else False
+    ):
         options["System`GraphLayout"] = String(graph_layout)
 
     g = Graph(G)
@@ -380,6 +384,19 @@ def __init__(self, Gr, **kwargs):
         self.G = Gr
         self.mixed = kwargs.get("mixed", False)
 
+        # Number of nodes
+        self.n: Optional[int] = None
+
+        # Here we define types that appear on some, but not all
+        # graphs. So these are optional, which we given an initial
+        # value of None
+
+        # Some graphs has a second int parameter like HknHarary
+        self.n: Optional[int] = None
+
+        # Trees have a root
+        self.root: Optional[int] = None
+
     def __hash__(self):
         return hash(("Pymathics`Graph", self.G))
 

pymathics/graph/eval/parametric.py

@@ -36,7 +36,7 @@ def eval_full_rary_tree(
     self, r: Integer, n: Integer, expression, evaluation: Evaluation, options: dict
 ) -> Optional[Graph]:
     """
-    Call networkx to get a full_raray_tree using parameters, ``r`` and ``t``.
+    Call networkx to get a full_rary_tree using parameters, ``r`` and ``t``.
     """
     py_r = r.value