TypeError: unsupported operand type(s) for -: 'float' and 'method'

Question

伙计们，在阅读了类和对象之后，我正在尝试在 Python 中做一些练习，其中一个练习是创建一个帐户 Class 并编写将钱存入帐户的方法。每次我运行它时，我都会收到一个 TypeError 告诉我该操作数不支持 Floats 和 Methods。我觉得我很接近但错过了一些非常明显的东西。谁能告诉我我做错了什么以及如何解决这个问题？

class Account:
    def __init__(account, id, balance, rate):
        account.__id = id
        account.__balance = float(balance)
        account.__annualInterestRate = float(rate)

    def getMonthlyInterestRate(account):
        return (account.__annualInterestRate/12)
    def getMonthlyInterest(account):
        return account.__balance*(account.__annualInterestRate/12)   
    def getId(account):
        return account.__id
    def getBalance(account):
        return account.__balance
    def withdraw(account, balance):
        return (account.__balance) - (account.withdraw)
    def deposit(account, balance):
        return (account.__balance) + (account.deposit)

def main():
    account = Account(1122, 20000, 4.5)
    account.withdraw(2500)
    account.deposit(3000)
    print("ID is " + str(account.getId()))
    print("Balance is " + str(account.getBalance()))
    print("Monthly interest rate is" + str(account.getMonthlyInterestRate()))
    print("Monthly interest is " + str(account.getMonthlyInterest()))

main()

Answer 1

这个：

def withdraw(account, balance):
    return (account.__balance) - (account.withdraw)

应该看起来像这样：

def withdraw(self, amount):
    self.__balance -= amount

在 Python 中，我们总是将 class 内部方法称为 self。

将此应用到 class 的其余部分并清理一些东西：

class Account:
    def __init__(self, id, balance, rate):
        self.id = id
        self.balance = float(balance)
        self.annualInterestRate = float(rate)

    def getMonthlyInterestRate(self):
        return self.annualInterestRate / 12

    def getMonthlyInterest(self):
        return self.balance * self.getMonthlyInterestRate()

    def getId(self):
        return self.id

    def getBalance(self):
        return self.balance

    def withdraw(self, amount):
        self.balance -= amount

    def deposit(self, amount):
        self.balance += amount

TypeError: unsupported operand type(s) for -: 'float' and 'method'

TypeError: unsupported operand type(s) for -: 'float' and 'method'

python

typeerror