Introduction to the Modeling and Analysis of Complex Systems

308 CHAPTER 15. BASICS OF NETWORKSthe edges are all considered one-way. Symmetries are not maintained automatically, asillustrated in the following example:Code 15.8:>>> g = nx.DiGraph()>>> g.add_edge(’Josh’, ’Jess’)>>> g.edge[’Josh’][’Jess’][’love’] = True>>> g.edge{’Jess’: {}, ’Josh’: {’Jess’: {’love’: True}}}>>> g.edge[’Jess’][’Josh’][’love’]Traceback (most recent call last):File "", line 1, in g.edge[’Jess’][’Josh’][’love’]KeyError: ’Josh’>>>The last error message means that Jess doesn’t know a guy named Josh in this case,because the graph is asymmetric. Life is hard.Exercise 15.6of NetworkX.Represent the network shown in Exercise 15.1 as a Graph objectExercise 15.7 Represent a small social network around you (say, 10 people) aseither Graph or DiGraph object of NetworkX. Then add properties to nodes andedges, such as:• Node properties: full name, age, job, address, etc.• Edge properties: relationship, connection weight, etc.In the examples above, we manually constructed network models by adding or removingnodes and edges. But NetworkX also has some built-in functions that can generatenetworks of specific shapes more easily. Here are a few examples:Code 15.9: networkx-test2.pyimport networkx as nx