python新手范围不工作

Question

我正在做作业，我不明白为什么我的range(1,13)： 未更新最低月付款168.52剩余余额4111.89 但它确实更新了这个月。。。我希望这两件事随着时间的推移而更新，从1月到12月，他们只是不会为我更新。你知道吗

balance = 4213
annualInterestRate = 0.2
monthlyPaymentRate = 0.04
month = 0
Total_amount_paid = 0
for month in range(1,13):
    print('Month'), month
    minimumpayment =  balance * monthlyPaymentRate
    print('Minimum monthly payment'), ('%.2f' % minimumpayment)
    Monthly_interest_rate =  (annualInterestRate/12) 
    Monthly_unpaid_balance = balance - minimumpayment
    Updated_balance_each_month = Monthly_unpaid_balance * \
    (annualInterestRate / 12.0) + Monthly_unpaid_balance
    print('Remaining Balance'), ('%.2f' % Updated_balance_each_month)
    Total_amount_paid = Total_amount_paid + minimumpayment
    print 'Total paid', ('%.2f' % Total_amount_paid)
    print 'Remaining balance', ('%.2f' % Updated_balance_each_month)

Answer 1

将balance更改为：Updated_balance_each_month您永远不会更改变量balance，因为它在for循环外定义，对于整个程序保持在4213。你知道吗

# the results do not update after each month ='( 

Updated_balance_each_month = 4213
annualInterestRate = 0.2
monthlyPaymentRate = 0.04
month = 0
Total_amount_paid = 0
for month in range(1,13):
    print('Month'), month
    minimumpayment =  Updated_balance_each_month * monthlyPaymentRate
    print('Minimum monthly payment'), ('%.2f' % minimumpayment)
    Monthly_interest_rate =  (annualInterestRate/12) 
    Monthly_unpaid_balance = Updated_balance_each_month - minimumpayment
    Updated_balance_each_month = Monthly_unpaid_balance * \
    (annualInterestRate / 12.0) + Monthly_unpaid_balance
    print('Remaining Balance'), ('%.2f' % Updated_balance_each_month)
    Total_amount_paid = Total_amount_paid + minimumpayment
print 'Total paid', ('%.2f' % Total_amount_paid)
print 'Remaining balance', ('%.2f' % Updated_balance_each_month)

Month 1
Minimum monthly payment 168.52
Remaining Balance 4111.89
Month 2
Minimum monthly payment 164.48
Remaining Balance 4013.20
Month 3
Minimum monthly payment 160.53
Remaining Balance 3916.89
Month 4
Minimum monthly payment 156.68
Remaining Balance 3822.88
Month 5
Minimum monthly payment 152.92
Remaining Balance 3731.13
Month 6
Minimum monthly payment 149.25
Remaining Balance 3641.58
Month 7
Minimum monthly payment 145.66
Remaining Balance 3554.19
Month 8
Minimum monthly payment 142.17
Remaining Balance 3468.89
Month 9
Minimum monthly payment 138.76
Remaining Balance 3385.63
Month 10
Minimum monthly payment 135.43
Remaining Balance 3304.38
Month 11
Minimum monthly payment 132.18
Remaining Balance 3225.07
Month 12
Minimum monthly payment 129.00
Remaining Balance 3147.67
Total paid 1775.55
Remaining balance 3147.67