我正在实现一个图，我将一个Route类作为Edge类的子类。我尝试在Route类中添加“距离”功能，因此我的Route类的构造函数会覆盖Edge类的构造函数。
由于它们位于不同的模块中，我在Route类中使用了“from edge import *”;但是，程序（PyDev）仍然会抛出错误，Undefined variable：Edge
这是我的实施：
'''
An (directed) edge holds the label of the node where the arrow is coming from
and the label of the node where the arrow is going to
'''
class Edge:
'''
Constructor of the Edge class
'''
def __init__(self, fromLabel, toLabel):
self.__fromLabel = fromLabel
self.__toLabel = toLabel
'''
Get the label of the node where the arrow is coming from
@return the label of the node where the arrow is coming from
'''
def getFromLabel(self):
return self.__fromLabel
'''
Get the label of the node where the arrow is going to
@return the label of the node where the arrow is going to
'''
def getToLabel(self):
return self.__toLabel
from Edge import *
'''
A Route is inherited from the Edge class and is an edge specialized for the
CSAirGraph class
'''
class Route(Edge):
'''
Constructor of the Route class
'''
def __init__(self, fromLabel, toLabel, distance):
Edge.__init__(self, fromLabel, toLabel)
self.__distance = distance
'''
Get the distance between two adjacent cities
@return: the distance between two adjacent cities
'''
def getDistance(self):
return self.__distance