我一直在阅读Core Python编程书,作者展示了一个例子:
(4, 5) < (3, 5) # Equals false
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所以,我想知道,它是如何/为什么它等于假?python如何比较这两个元组?
顺便说一下,书中没有解释.
我正在尝试使用队列类中的PriorityQueue.但是,我在将自定义对象放入PQ时遇到问题.我已经实现了__cmp__以下功能:
def __cmp__(self, other):
return (self.priority > other.priority) - (self.priority < other.priority)
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我希望PriorityQueue按优先级字段排序,在init函数中指定:
def __init__(self, board, priority=0):
self.priority = priority
# Other logic
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但是,当我运行代码将一个State对象插入PQ时,我收到此错误: TypeError: '<' not supported between instances of 'State' and 'State'
这是运行PQ的代码.
if op.precond(S):
new_state = op.state_transf(S)
if not (OPEN.queue.__contains__(new_state)) and not (new_state in CLOSED):
GVALUES[Problem.hash(new_state)] = get_distance_value(op, new_state)
HEUR_VALUES[Problem.hash(new_state)] = get_AStar_value(new_state)
print("NEW STATE: " + str(new_state))
OPEN.put(new_state)
print("OPEN: " + str(OPEN.queue))
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其中OPEN是priorityQueue.
任何帮助都将非常感谢...因为将值插入PQ应该非常简单.