def read_graph_from_file(file_name):
'''Read graph from a file'''
file = open(file_name, 'r')
file_list = file.readlines()
vertices = file_list[1].rstrip().split(',')
valid_types = 'gGdD'
graph_type = ''
directed = False
weighted = False
edges_list = []
if file_list[0].rstrip() in valid_types:
graph_type = file_list[0].upper()
else:
raise ValueError('G or D is not specified')
if graph_type == 'D':
directed = True
for item in range(2, len(file_list)):
edge = file_list[item].rstrip().replace('(', '').replace(')', '').split(',')
if len(edge) == 3:
weighted = True
edges_list.append(edge)
graph = Graph(weighted, directed)
for edge in edges_list:
if weighted:
graph.add_weighted_edge(int(edge[0]), int(edge[1]), int(edge[2]))
else:
graph.add_edge(int(edge[0]), int(edge[1]))
return graph
def test_get_edge_list(self):
g = Graph(weighted=True, directed=False)
g.add_weighted_edge('A', 'B', 5)
g.add_weighted_edge('C', 'D', 3)
g.add_weighted_edge('E', 'F', 2)
g.add_weighted_edge('G', 'H', 1)
self.assertCountEqual(g.get_edge_list(), [('A', 'B', 5), ('C', 'D', 3),
('E', 'F', 2),
('G', 'H', 1)])
