def load_graph(path, mode, directed):
f = open(path, 'r+')
for line in f.readlines():
vals = [int(val) for val in line.split(' ')]
if len(vals) == 2:
if mode == 'matrix':
graph = Matrix(vals[1])
else:
graph = ListGraph(vals[1])
else:
if mode == 'matrix':
graph.set(vals[0], vals[1], vals[2])
if directed and graph.get(vals[1], vals[0]) == 0:
graph.set(vals[1], vals[0], -1)
else:
graph.set(vals[1], vals[0], vals[2])
else:
graph.add_connection(vals[0], vals[1], vals[2])
if not directed:
graph.add_connection(vals[1], vals[0], vals[2])
return graph
def generate_graph_nx(
nodes: int,
density,
mode,
directed,
force=settings.force): # graph generation using networkx
bar = ProgBar(20, title='Generating graph', stream=sys.stdout)
if directed: # calculate edge count based on node count and density
edges = nodes * (nodes - 1) * density
if edges < nodes - 1 and not force:
print(
"Minimum graph density for this problem is {:2.0%}. "
"To generate less dense graph anyway, set argument force to True."
.format(float(1 / nodes)),
file=sys.stderr)
edges = nodes - 1
else:
edges = nodes * (nodes - 1) * density / 2
if edges < nodes - 1 and not force:
print(
"Minimum graph density for this problem is {:2.0%}. "
"To generate less dense graph anyway, set argument force to True."
.format(float(2 / nodes)),
file=sys.stderr)
edges = nodes - 1
bar.update()
G = nx.generators.random_graphs.gnm_random_graph(
nodes, edges, directed=directed) # generate random graph
bar.update()
if not directed: # check connectivity and generate new graph if failed
while not nx.is_connected(G):
G = nx.generators.random_graphs.gnm_random_graph(
nodes, edges, directed=directed)
else:
cont = False
while not cont:
cont = True
for node in G.nodes:
if len([x for x in G.neighbors(node)]) == 0:
cont = False
G = nx.generators.random_graphs.gnm_random_graph(
nodes, edges, directed=directed)
break
bar.update()
if mode == 'matrix': # convert generated networkx graph to own structure
ret = Matrix(nodes)
for x, y in G.edges:
w = randint(1, nodes)
ret.set(x, y, w)
if directed and ret.get(y, x) == 0:
ret.set(y, x, 0)
else:
ret.set(y, x, w)
bar.update()
return ret
else:
ret = ListGraph(nodes)
for x, y in G.edges:
w = randint(1, nodes)
ret.add_connection(x, y, w)
if not directed:
ret.add_connection(y, x, w)
bar.update()
return ret
