Question

how do you accumulate total amount paid in this program

Answer 1

##OB = Outstanding Balance
##AIR = Annual Interest Rate
##MMPP = Minimum Monthly Payments Percentage
##MMP = Minimum Mnthly Payments
##IP = Interest Paid
##PP = Principal Paid
##RB = Remaining Balance

OB=int(raw_input("Enter Outstanding Balance:"))
AIR=float(raw_input("Enter Interest Rate(decimal):"))
MMPP=float(raw_input("Enter Minimum Monthly Payment Percent(decimal):"))

##for loop each month of the year

for month in range(1, 13):
print "Month:",month

##calculate minimum monthly payment
##print the min monthly payment

MMP = MMPP*OB
print "Minimum Monthly Payment:",round(MMP, 2)

##calculate interest paid
##Print Interest Paid

IP =(AIR/12.0)*OB
print "Interest Paid:",round(IP, 2)

##Calculate Principal Paid,
##print Principal Paid

PP = MMP-IP
print "Principal Paid:",round(PP, 2)

##Remaining Balanace
##print Remaining Balance

RB = OB-PP
print "Remaining Balance:",round(RB, 2)

##Total Amount Paid
##print Total Ammount Paid and Remaing Balance

OB=OB-PP

print "RESULT:"
print "Remaining Balance:",round(RB, 2)

Answer 2

the total amount paid is the IP + PP but, I dont know how to make it accumulate every month

Answer 3

start with some variable for the total and initialize it to 0. every time you make a payment, you add to total with a line like
```
total = total + (monthlyPayment)
```

Answer 4

Im not looking for the total im looking for the amount that I paid towards the total. I tried making total amount paid = to Interest paid + principal paid but it only made it how much it paid for the month.

Answer 5

could you link the pdf of the problem again please? they give the equations, you just have to put them in the right place

Answer 6

http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-00sc-introduction-to-computer-science-and-programming-spring-2011/unit-1/lecture-4-machine-interpretation-of-a-program/MIT6_00SCS11_ps1.pdf

Answer 7

yeah at the end it wants how much spent in total.

Answer 8

so what part do you need exactly? the amount paid each month is the minimum monthly payment. which value are you having trouble finding?

Answer 9

I need a value for the accrument of all 12 minimum monthly payments.

Answer 10

that would be the total amount paid....
or do you want the total remaining balance?

Answer 11

on the pdf:
RESULT
Total amount paid: $1131.12 <-- is this what you want?
Remaining balance: $4611.46

Answer 12

yes I need the total amount paid

Answer 13

so what i wrote above will work
at the top of your code, *before* the for loop, initiate a variable for the total payment to 0
```
total = 0
## your other initializations
for month in range(1, 13):
total = total + minMonthlyPayment
## rest of your calculations for each month
print total
```
on every iteration, the value minMonthlyPayment will be added to total, and so printing it out at the end will give the total amount paid

Answer 14

ohhh ok I miss read it, so instead of putting total I would be putting TAP?

Answer 15

the name of the variable doesn't matter; you can call it whatever you like (there are some exceptions: i.e. can't start a variable with a number etc). By convention, variables written all in caps are reserved for global variables, which total shouldn't be (it could but that is bad design). You could call the variable that holds the total amount paid 'foo', but that doesn't mean anything.
Learning good naming conventions is an important part of programming.

Answer 16

so whether you call it total or totalAmountPaid or TAP or FOOOOOOOOO, it's just a box that holds a number. make sure you know what it means, and print it at the end

Answer 17

so the varaible names that I assigned really should be lowercase?

Answer 18

this whole program set up is pretty bad huh? I should have listed all my initializations should have been together and then my print statements afterwards

Answer 19

ideally, yes. your program will run fine as is, but it is simply a convention between programmers to use certain patterns
caps for global variables
example: TOTAL_PAID
"camel casing" or underscores for functions and normal 'scoped' variables
example: totalPaid, total_paid
capitalized first letter for classes (you haven't studied those yet)
example: class TotalPaid

Answer 20

I was at one point doing a online class on java and we went over classes. so im guessing thats when you make a varaible in one class you would us class <class name> to call a variable from a certain class

Answer 21

use*

Answer 22

yeah, but that is normal for a first go
you want something like
```
## initialize variables, including total
outstandingBalance = raw_input("Outstanding Balance: ")
annualInterestRate = raw_input("annual Interest Rate: ")
minMonthlyPaymentRate = raw_input("Minimum Monthly Payment Rate (as decimal): ")
totalPaid = 0
## for each month of theyear
for month in range (1, 13):
## do calculations
minMonthlyPayment = minMonthlyPaymentRate * outstandingBalance
interestPaid = annualInterestRate/12 * outstandingBalance
principlePaid = minMonthlyPayment - interestPaid
outstandingBalance = outstandingBalance - principlePaid
totalPaid = totalPaid + minMonthlyPayment
## print out values
print "Month: ", month
print "Minimum Monthly Payment: ", minMonthlyPayment
print "Principal Paid: ", principlePaid
print "Remaining Balance: ", outstandingBalance
print "RESULT"
print "Total Paid: ", totalPaid
print "Remaining Balance: ", outstandingBalance
```

Answer 23

there i think i just wrote the answer for you, though i didn't really intend to. I didn't try running that, so if it doesn't work it's your job to debug. Hopefully you see the structure
1) initializations
2) loop with calculations
3) final results printed

Answer 24

thats perfect even though my program works the same way the structure to yours is so much better!

Answer 25

right, often two program that produce the same results differ drastically in their structure and approach. writing clear, legible, well-organized code is important, because when you write ir professionally, you want someone 5 years later to be able to pick up your code and follow it without too much difficulty. It also makes debugging a lot easier when your code is well organized

Answer 26

thanks again your the man

Answer 27

np

Answer 28

just to mention something to all that are trying to solve credit card problem, U might find useful the loop material that is on the MIT portaland go through it cuz once u understand loops perfectly then by applying simple maths that becomes a solution for this particular problem.