尝试在column_property中使用float()

发布于 2024-12-09 03:57:19 字数 602 浏览 0 评论 0原文

我试图在使用 column_property 分配列时将列转换为浮点数：

class voteinfo(Base):
    __tablename__ = 'voteinfo'
    id = Column(Integer, primary_key=True)
    upvotes = Column(Integer)
    downvotes = Column(Integer)
    controversial = column_property(float(upvotes - downvotes)/(abs(upvotes + downvotes)+1)

    def __init__(self, upvotes, downvotes):
        self.upvotes = upvotes
        self.downvotes = downvotes

但是，当我运行此命令时，出现以下错误：

TypeError: float() argument must be a string or a number

有更好的方法来执行此操作吗？我使用 column_property 是因为我希望能够按有争议的进行排序。

原文

I'm trying to convert a column into a float while assigning a column using column_property:

class voteinfo(Base):
    __tablename__ = 'voteinfo'
    id = Column(Integer, primary_key=True)
    upvotes = Column(Integer)
    downvotes = Column(Integer)
    controversial = column_property(float(upvotes - downvotes)/(abs(upvotes + downvotes)+1)

    def __init__(self, upvotes, downvotes):
        self.upvotes = upvotes
        self.downvotes = downvotes

However, when I run this, I get the following error:

TypeError: float() argument must be a string or a number

Is there a better way to do this? I'm using column_property because I want to be able to sort by controversial.

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请止步禁区 2024-12-16 03:57:19

从 sqlalchemy 文档中，最好的方法是这样做的目的是定义一个 python @property。您还需要使用内置的 sqlalchemy float 类型。

from sqlalchemy.types import Float

class voteinfo(Base):
    __tablename__ = 'voteinfo'
    id = Column(Integer, primary_key=True)
    upvotes = Column(Integer)
    downvotes = Column(Integer)

    @property
    def controversial(self):
        return Float(self.upvotes - self.downvotes)/Float(abs(self.upvotes + self.downvotes)+1)


    def __init__(self, upvotes, downvotes):
        self.upvotes = upvotes
        self.downvotes = downvotes

From the sqlalchemy docs, the best way to do this is to define a python @property. You also need to use the built-in sqlalchemy float type.

from sqlalchemy.types import Float

class voteinfo(Base):
    __tablename__ = 'voteinfo'
    id = Column(Integer, primary_key=True)
    upvotes = Column(Integer)
    downvotes = Column(Integer)

    @property
    def controversial(self):
        return Float(self.upvotes - self.downvotes)/Float(abs(self.upvotes + self.downvotes)+1)


    def __init__(self, upvotes, downvotes):
        self.upvotes = upvotes
        self.downvotes = downvotes

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