Question

一个学校项目要求我执行一个函数，该函数应返回四舍五入到小数点后两位数的月度付款的绝对值。

谁能解释我为什么我的代码无法正常工作？预先感谢！

interest_rate= int(input('Type your interest rate (in %) '))
principal = int(input('Type your principal '))
period = int(input('Type for how many months '))

def calculate_payment(principal, interest_rate, period):
    final_amount = (1 + interest_rate) ** period
    return principal * (interest_rate * final_amount) / 
    (final_amount- 1)

final_amount = str(round(final_amount, 2))

print("your amount that has to be paid after each month is: ", final_amount)

Answer 1

我认为，您既会误解复利的公式（除了堆栈溢出），也不会详细说明利率的期限（利率是每月还是每年？）。如果利率是每月，并且您将返回一个月后将支付的利息，那么可变期限是没有用的。关于代码，您没有正确定义函数，也没有正确调用它以使其起作用。此外，如果是复利，则每月支付的（利息）价值将永远不相等，因为除非利息被提取且不进行再投资。如果是您要的，请检查案例2 。情况1假设您要在操作完成时退还全部款项。

这是我认为您要寻找的：

案例1

interest_rate= int(input('Type your interest rate (in %) '))
principal = int(input('Type your principal '))
period = int(input('Type for how many months '))

def calculate_payment(principal, interest_rate, period):
    final_amount = principal * ((1+interest_rate/100) ** period)
    return round(final_amount,2)

print("your amount that has to be paid at the end of the period is: ", calculate_payment(principal, interest_rate,period))

输出：

Type your interest rate (in %) 10
Type your principal 1000
Type for how many months 2
your amount that has to be paid at the end of the period is:  1210.0

案例2

interest_rate= int(input('Type your monthly interest rate (in %) '))
principal = int(input('Type your principal '))
period = int(input('Type for how many months '))

def calculate_payment(principal, interest_rate, period):
    final_amount = principal * (((1+interest_rate/100)) - 1)
    return round(final_amount,2)

print("your amount that has to be paid after each month is: ", calculate_payment(principal, interest_rate,period))

输出：

Type your monthly interest rate (in %) 10
Type your principal 1000
Type for how many months 2
your amount that has to be paid after each month is:  100.0

为什么我的四舍五入到两位小数对我的代码不起作用？

1 个答案:

案例1

案例2