如何处理"解压缩的值太多"

Question

我已经检查了一些想法和原因,下面针对这个问题进行了调查...... "太多值解包"异常 (Stefano Borini的解释)

但是在这里,我正在迭代列表作为理解列表并将结果移动到列表中......!所以输入的数量读取输出变量的数量,即tempList......

然后,这个过程出了什么问题？!

def DoProcess(self, myList):
    tempList = []
    tempList = [[x,y,False] for [x,y] in myList]
    return tempList

编辑1:myList是列表,就像[[x1, y1], [x2, y2], [x3, y3], [x4 y4]].

class Agent(object):
    def __init__(self, point = None):
        self.locationX = point.x
        self.locationY = point.y

    def __iter__(self):
        return self

    def __next__(self):
        return [self.locationX, self.locationY]

    def __getItem__(self):
        return [self.locationX, self.locationY]

    def GenerateAgents(self, numberOfAgents):
        agentList = []
        while len(agentList) < numberOfAgents:

            point = Point.Point()
            point.x = random.randint(0, 99)
            point.y = random.randint(0, 99)

            agent = Agent(point)
            agentList.append(agent)
        return agentList

    def DoProcess(self, myList):
        tempList = []
        tempList = [[x[0],x[1],False] for x in myList]
        return myList

每个Point都有两个属性locationX和locationY...

Answer 1

你的实施存在Agent严重缺陷; 你创造了一个无限的发电机

def __iter__(self):
    return self

def __next__(self):
    return [self.locationX, self.locationY]

这将永远产生具有两个值的列表.尝试在元组赋值中使用此对象将产生至少3个这样的值(对于x和y目标而言为2 ,再加上Python的一个,以便知道有更多值要解压缩而不是请求).Python __next__每次在序列中需要另一个值时都会调用它,并且[x, y]每次都会返回代码.永远永远.

该__iter__方法应该返回两个值的实际迭代:

def __iter__(self):
    for value in (self.locationX, self.locationY):
        yield value

甚至只是

def __iter__(self):
    yield self.locationX
    yield self.locationY

放弃__next__了.然后,上面的生成器将生成两个值,然后StopIteration正确引发,并使用元组赋值.

该__getitem__方法拼写全部小写并采用索引参数:

def __getitem__(self, index):
    return (self.locationX, self.locationY)[index]

现在,0映射到locationX和1到locationY.

使用这些更改重写代码:

class Agent(object):
    def __init__(self, point):
        self.locationX = point.x
        self.locationY = point.y

    def __iter__(self):
        yield self.locationX
        yield self.locationY

    def __getitem__(self, index):
        return (self.locationX, self.locationY)[index]

    def GenerateAgents(self, numberOfAgents):
        agentList = []
        for _ in range(numberOfAgents):
            point = Point.Point()
            point.x = random.randint(0, 99)
            point.y = random.randint(0, 99)

            agent = Agent(point)
            agentList.append(agent)
        return agentList

    def DoProcess(self, myList):
        return [[x, y, False] for x, y in myList]