feature_collection.py 文件源码

def __isub__(self, other):
        '''
        In-place subtract features from two FeatureCollections.

        >>> fc1 = FeatureCollection({'foo': Counter('abbb')})
        >>> fc2 = FeatureCollection({'foo': Counter('bcc')})
        >>> fc1 -= fc2
        FeatureCollection({'foo': Counter({'b': 2, 'a': 1})})

        Note that if a feature in either of the collections is not an
        instance of :class:`collections.Counter`, then it is ignored.
        '''
        if self.read_only:
            raise ReadOnlyException()
        fc = self.merge_with(other, operator.isub)
        self._features = fc._features
        return self