def generate_graph(p, max_edges_to_create_per_node_per_pass):
'''
generate a semi-random graph of size p
generate p vertices, with random x,y co-ords
for each vertex:
randomly add at most max_edges_to_create_per_node_per_pass new edges
'''
g = nx.Graph()
f_gen_xy = construct_xy_factory()
for i in range(p):
(x,y) = f_gen_xy()
tag = Tag(x, y, '')
tag.label = 'Node %i' % tag.idx
g.add_node(tag)
nodes = g.nodes()
for node in nodes:
for j in range(randint(1, max_edges_to_create_per_node_per_pass)):
new_edge_added = False
while new_edge_added == False:
z = randint(0, len(nodes) - 1)
if nodes[z] != node:
if ((nodes[z], node) not in g.edges()) and ((node, nodes[z]) not in g.edges()):
g.add_edge(node, nodes[z])
new_edge_added = True
return g
def add_node_to_graph_at_random(graph):
(x, y) = calc_xy_for_new_node(graph)
tag = Tag(x, y, '')
tag.label = 'Node %i' % tag.idx
graph.add_node(tag)
add_edges_for_vertex_at_random(graph, tag, max_edges_to_create_per_node_per_pass=4)
return tag
