Question

我正在努力使EFeatureObjective成为抽象，我知道我可以实现一个类，只是使calculate_feature_scores成为抽象，但是我所做的事情-

class EFeatureObjective(bluepyopt.objectives.Objective):

    """EPhys feature objective"""

    def __init__(self, name, features=None):
        """Constructor
        Args:
            name (str): name of this object
            features (list of eFeatures): features used in the Objective
        """

        super(EFeatureObjective, self).__init__(name)
        self.name = name
        self.features = features

    def calculate_feature_scores(self, responses):
        """Calculate the scores for the individual features"""

        scores = []
        for feature in self.features:
            scores.append(feature.calculate_score(responses))

        return scores


class SingletonObjective(EFeatureObjective):

    """Single EPhys feature"""

    def __init__(self, name, feature):
        """Constructor
        Args:
            name (str): name of this object
            features (EFeature): single eFeature inside this objective
        """

        super(SingletonObjective, self).__init__(name, [feature])

    def calculate_score(self, responses):
        """Objective score"""

        return self.calculate_feature_scores(responses)[0]

    def __str__(self):
        """String representation"""

        return '( %s )' % self.features[0]

我使用EFeatureObjective将ABC = abc.ABCMeta('ABC', (object,), {'__slots__': ()})设为抽象，并且拥有

    def calculate_feature_scores(self, responses):                                   
         pass

喜欢

 import abc                                                                           

 ABC = abc.ABCMeta('ABC', (object,), {'__slots__': ()})                               


 class EFeatureObjective(bluepyopt.objectives.Objective, ABC):                           

      """EPhys feature objective"""                                                       
      def __init__(self, name, features=None):                                            
            """Constructor                                                                  

            Args:                                                                           
            name (str): name of this object                                             
            features (list of eFeatures): features used in the Objective                
            """                                                                             

            super(EFeatureObjective, self).__init__(name)                                   
            self.name = name                                                                
            self.features = features                                                        

      @abc.abstractmethod                                                                 
      def calculate_feature_scores(self, responses):    
          pass


 class SingletonObjective(EFeatureObjective):
       .........
       def calculate_feature_scores(self, responses):                                   
           """Calculate the scores for the individual features"""                       

           scores = []                                                                  
           for feature in self.features:                                                
           scores.append(feature.calculate_score(responses))                        

           return scores

然后我在SingletonObjective中实现了此方法，问题在于语法是否可以实现？ features中没有SingletonObjective。基本上EFeatureObjective在(list of eFeatures)上运行，而SingletonObjective在single eFeature inside this objective上运行。

然后我在EFeatureObjective内部调用了抽象类calculate_feature_scores抽象方法SingletonObjective，就像

 def calculate_feature_scores(self, responses):
     super(SingletonObjective, self).calculate_feature_scores(responses)

但随后

 def calculate_score(self, responses):                                               
         """Objective score"""                                                           

         return self.calculate_feature_scores(responses)[0]

索引会出错。

我已经花了一段时间，现在，我希望EFeatureObjective是抽象的，而无需创建使用不同Python版本的类。感谢任何答案。

Answer 1

如果您想要一个不能实例化但可以子类化的类，那么可以通过以下方法实现：

class BaseClass(object):
  def __new__(cls):
    ''' If this is not a subclass being instanciated, then raise an error '''
    if cls is BaseClass:
      raise TypeError('Cannot instantiate this')
    return object.__new__(cls)

   AbstractMethod1 = None

   def __init_subclass__(cls):
     ''' Anytime subclasses are created, make sure they have the right methods '''
     if cls.AbstractMethod1 is None:
       raise TypeError('All subclasses of `base` must define `AbstractMethod1`')

使用Python将类抽象化

1 个答案: