How do I write function to test if a graph is apex?
I am working on topological graph theory problems and using SageMath. I want to create a function that give a boolean True or False answer, so I can use this answer for further use. My current function that I use:
def is_apex(a): for v in a.vertex_iterator(): l=a.neighbors(v) if a.is_planar(a.delete_vertex(v)): print("Deleting vertex ",v," makes a planar graph") a.add_vertex(v) a.add_edges([(v, y) for y in l]) else: a.add_vertex(v) a.add_edges([(v, y) for y in l]) print("Deleting vertex ",v," does not make a planar graph")
I am a noob when it comes to programming, and any help would be awesome.
I want a True returned if the graph is apex and a False value to return for not apex.