生成森林的逻辑问题

[weilycoder]

cyaron/cyaron/graph.py

Lines 538 to 553 in 23f6432

	@staticmethod
	def forest(point_count, tree_count, **kwargs):
	"""
	Return a forest with point_count vertexes and tree_count trees.
	Args:
	point_count: the count of vertexes
	tree_count: the count of trees
	"""
	if tree_count <= 0 or tree_count > point_count:
	raise ValueError("tree_count must be between 1 and point_count")
	tree = list(Graph.tree(point_count, **kwargs).iterate_edges())
	result = Graph(point_count, 0)
	need_add = random.sample(tree, len(tree) - tree_count + 1)
	for edge in need_add:
	result.add_edge(edge.start, edge.end, weight=edge.weight)
	return result

注意一下这一行：

cyaron/cyaron/graph.py

Line 549 in 23f6432

result = Graph(point_count, 0)

作者将 Graph 的第二项参数错误地理解为边数并传入 $0$。实际上，这项参数指定了图是否有向。

同时，我们看到，这个函数并没有解析用户可能传入的 directed 参数并进行处理。