Fixed database typo and removed unnecessary class identifier.

venv/share/doc/networkx-2.5/examples/subclass/plot_printgraph.py

@@ -0,0 +1,87 @@
+"""
+===========
+Print Graph
+===========
+
+Example subclass of the Graph class.
+"""
+
+import matplotlib.pyplot as plt
+import networkx as nx
+from networkx import Graph
+
+
+class PrintGraph(Graph):
+    """
+    Example subclass of the Graph class.
+
+    Prints activity log to file or standard output.
+    """
+
+    def __init__(self, data=None, name="", file=None, **attr):
+        Graph.__init__(self, data=data, name=name, **attr)
+        if file is None:
+            import sys
+
+            self.fh = sys.stdout
+        else:
+            self.fh = open(file, "w")
+
+    def add_node(self, n, attr_dict=None, **attr):
+        Graph.add_node(self, n, attr_dict=attr_dict, **attr)
+        self.fh.write(f"Add node: {n}\n")
+
+    def add_nodes_from(self, nodes, **attr):
+        for n in nodes:
+            self.add_node(n, **attr)
+
+    def remove_node(self, n):
+        Graph.remove_node(self, n)
+        self.fh.write(f"Remove node: {n}\n")
+
+    def remove_nodes_from(self, nodes):
+        for n in nodes:
+            self.remove_node(n)
+
+    def add_edge(self, u, v, attr_dict=None, **attr):
+        Graph.add_edge(self, u, v, attr_dict=attr_dict, **attr)
+        self.fh.write(f"Add edge: {u}-{v}\n")
+
+    def add_edges_from(self, ebunch, attr_dict=None, **attr):
+        for e in ebunch:
+            u, v = e[0:2]
+            self.add_edge(u, v, attr_dict=attr_dict, **attr)
+
+    def remove_edge(self, u, v):
+        Graph.remove_edge(self, u, v)
+        self.fh.write(f"Remove edge: {u}-{v}\n")
+
+    def remove_edges_from(self, ebunch):
+        for e in ebunch:
+            u, v = e[0:2]
+            self.remove_edge(u, v)
+
+    def clear(self):
+        Graph.clear(self)
+        self.fh.write("Clear graph\n")
+
+
+G = PrintGraph()
+G.add_node("foo")
+G.add_nodes_from("bar", weight=8)
+G.remove_node("b")
+G.remove_nodes_from("ar")
+print("Nodes in G: ", G.nodes(data=True))
+G.add_edge(0, 1, weight=10)
+print("Edges in G: ", G.edges(data=True))
+G.remove_edge(0, 1)
+G.add_edges_from(zip(range(0, 3), range(1, 4)), weight=10)
+print("Edges in G: ", G.edges(data=True))
+G.remove_edges_from(zip(range(0, 3), range(1, 4)))
+print("Edges in G: ", G.edges(data=True))
+
+G = PrintGraph()
+nx.add_path(G, range(10))
+nx.add_star(G, range(9, 13))
+nx.draw(G)
+plt.show()