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How to raw_input data when using user defined functions:

Hi i am new to programming and just started learning python i wrote the below code /program to prompt hours and rate per hour using raw_input to compute gross pay. i tried to initiate time-and-a-half for the hourly rate for all hours worked above 40 hours. the logic to do the computation of time-and-a-half in a function called computepay() and use the function to do the computation. The function should return a value. i used 45 hours and a rate of 10.50 per hour to test the program (the pay should return 498.75). i tried using raw_input to read a string and float() to convert the string to a number. i Don't name my variable sum or use the sum() function. i am able to print the output but i need to input the data when prompted unlike inputing the value in "line16"
def computePay (hours,rate):
if hours > 40:
overtimerate = 1.5 * rate
overtime = (hours-40) * overtimerate
overtimepay = overtime + (40 * rate)
return overtimepay;
else:
normalpay = hours * rate
return normalpay;
hours = raw_input('Enter hours: ')
hrs = int(hours)
rate = raw_input('Enter rate: ')
r = float(rate)
p = computePay(45,10.50)
print p

Assumptions:
I had to make the following assumptions in understanding your question:
Looking at your print statement, You are using python2.x
You want to computePay using the user inputted hours and rate.
Problem:
In the following line you are using constant hrs and r values instead of using the user inputed values
p = computePay(45,10.50)
Solution:
If you want to use user inputted values to compute the pay, you need to call the function as follows:
p = computePay(hrs, r)
With this line you are essentially asking python to computePay using the values stored in the variables hrs and r.
Final Code:
Therefore your final code should like this:
def computePay (hours,rate):
if hours > 40:
overtimerate = 1.5 * rate
overtime = (hours-40) * overtimerate
overtimepay = overtime + (40 * rate)
return overtimepay;
else:
normalpay = hours * rate
return normalpay;
hours = raw_input('Enter hours: ')
hrs = int(hours)
rate = raw_input('Enter rate: ')
r = float(rate)
p = computePay(hrs,r)
print p
Sample Output:
Enter hours: 55
Enter rate: 20
1250.0

If you mean by that you want the arguments to equal the inputs rather than the ones inputted manually, you should do instead:
p = computePay(hrs, r)
Example output:
Enter hours: 45
Enter rate: 10.5
498.75

Calculating Compound Interest using Python functions

Write a function that computes the balance of a bank account with a given initial balance and interest rate, after a given number of years. Assume interest is compounded yearly.
I am having the error " ValueError: unsupported format character 'I' (0x49) at index 28"
Here is my code so far.
def BankBalance():
InputB = 1000
return InputB
print("Your initial balance is $1000")
def Interest():
InputI = 0.05
return InputI
print("The rate of interest is 5%")
def CountNumber():
InputN = float(input("Please enter the number of times per year you would like your interest to be compounded: "))
return InputN
def Time():
InputT = float(input("Please enter the number of years you need to compund interest for:"))
return InputT
def Compount_Interest(InputB, InputI, InputT, InputN):
Cinterest = (InputB*(1+(InputI % InputN))**(InputN * InputT))
print("The compound interest for %.InputT years is %.Cinterest" %Cinterest)
B = BankBalance()
I = Interest()
N = CountNumber()
T = Time()
Compount_Interest(B, I, N, T)

Here is how you would do it.
def main():
# Getting input for Balance
balance = float(input("Balance: $ "))
# Getting input for Interest Rate
intRate = float(input("Interest Rate (%) : "))
# Getting input for Number of Years
years = int(input("Years: "))
newBalance = calcBalance(balance, intRate, years)
print ("New baance: $%.2f" %(newBalance))
def calcBalance(bal, int, yrs):
newBal = bal
for i in range(yrs):
newBal = newBal + newBal * int/100
return newBal
# Program run
main()

You are trying to use your variable as a function.
Try this instead :
Cinterest = (InputB * (1+(InputI % InputN))**(InputN * InputT))

Python, and most other programming languages, don't assume that two adjacent mathematical expressions with no operator between them means multiplication. You are missing a multiplication operator (*) between InputB and the rest of the expression:
Cinterest = (InputB * (1+(InputI % InputN))**(InputN * InputT))
# Here -------------^

Python CD annual precentage

I am doing this assignment. when i input the number of months it is one printing one month. rather it be 5 months or 17 months its only printing 1 months total.
https://drive.google.com/file/d/0B_K2RFTege5uZ2M5cWFuaGVvMzA/view?usp=sharing
Here is what i have so far what am i over looking thank you
calc = input('Enter y or n to calculate your CDs worth?')
month= int(input('Select your number of months'))
while calc == 'y':
while month > 0:
amount = int(input('Please enter the amount:'))
percent= float(input('Please enter the annual percentage:'))
calc= amount + amount* percent/ 1200
print(calc)

You would want to use a for loop rather than while in this sense since you are doing a set amount of operations. You also were reusing calc and assigning calc to from a String to a float, generally a bad idea. The main problem is the formula builds upon the previously calculated number, it starts off with the initial amount entered, 10000 + 10000 * 5.75 / 1200 = 10047.91, then uses 10047.91 in the next calculation, instead of 10000, you never were reusing the previously calculated number, so you weren't getting the right answer. This should do it:
calc = input('Enter y or n to calculate your CDs worth?')
if calc == 'y':
month = int(input('Select your number of months'))
amount = int(input('Please enter the amount:'))
percent = float(input('Please enter the annual percentage:'))
for i in range(month):
if i == 0:
calcAmount = amount + ((amount * percent) / 1200)
else:
calcAmount = calcAmount + ((calcAmount * percent) / 1200)
print calcAmount

Calculating mortgage interest in Python

I am currently learning python through a video tutorial on youtube, and have come up against a formula I cannot seem to grasp, as nothing looks right to me. The basic concept of the excersise is to make a mortgage calculator that asks the user to input 3 pieces of information, Loan Amount, Interest Rate, and Loan Term (years)
then it calculates the monthly payments to the user. here is my code:
__author__ = 'Rick'
# This program calculates monthly repayments on an interest rate loan/mortgage.
loanAmount = input("How much do you want to borrow? \n")
interestRate = input("What is the interest rate on your loan? \n")
repaymentLength = input("How many years to repay your loan? \n")
#converting the string input variables to float
loanAmount = float(loanAmount)
interestRate = float(interestRate)
repaymentLength = float(repaymentLength)
#working out the interest rate to a decimal number
interestCalculation = interestRate / 100
print(interestRate)
print(interestCalculation)
#working out the number of payments over the course of the loan period.
numberOfPayments = repaymentLength*12
#Formula
#M = L[i(1+i)n] / [(1+i)n-1]
# * M = Monthly Payment (what were trying to find out)
# * L = Loan Amount (loanAmount)
# * I = Interest Rate (for an interest rate of 5%, i = 0.05 (interestCalculation)
# * N = Number of Payments (repaymentLength)
monthlyRepaymentCost = loanAmount * interestCalculation * (1+interestCalculation) * numberOfPayments / ((1+interestCalculation) * numberOfPayments - 1)
#THIS IS FROM ANOTHER BIT OF CODE THAT IS SUPPOSE TO BE RIGHT BUT ISNT---
# repaymentCost = loanAmount * interestRate * (1+ interestRate) * numberOfPayments / ((1 + interestRate) * numberOfPayments -1)
#working out the total cost of the repayment over the full term of the loan
totalCharge = (monthlyRepaymentCost * numberOfPayments) - loanAmount
print("You want to borrow £" + str(loanAmount) + " over " + str(repaymentLength) + " years, with an interest rate of " + str(interestRate) + "%!")
print("Your monthly repayment will be £" + str(monthlyRepaymentCost))
print("Your monthly repayment will be £%.2f " % monthlyRepaymentCost)
print("The total charge on this loan will be £%.2f !" % totalCharge)
Everything works, but the value it throws out at the end is completely wrong... a £100 loan with an interest rate of 10% over 1 year shouldn't be making me pay £0.83 per month. Any help in getting my head around this equation to help me understand would be greatly appreciated.

With the help of examples, this is what I did.
# Formula for mortgage calculator
# M = L(I(1 + I)**N) / ((1 + I)**N - 1)
# M = Monthly Payment, L = Loan, I = Interest, N = Number of payments, ** = exponent
# Declares and asks for user to input loan amount. Then converts to float
loanAmount = input('Enter loan amount \n')
loanAmount = float(loanAmount)
# Declares and asks user to input number of payments in years. Then converts to float. Years * 12 to get
# total number of months
years = input('How many years will you have the loan? \n')
years = float(years) * 12
# Declares and asks user to input interest rate. Then converts to float and input interest rate is /100/12
interestRate = input('Enter Interest Rate \n')
interestRate = float(interestRate) / 100 / 12
# Formula to calculate monthly payments
mortgagePayment = loanAmount * (interestRate * (1 + interestRate)
** years) / ((1 + interestRate) ** years - 1)
# Prints monthly payment on next line and reformat the string to a float using 2 decimal places
print("The monthly mortgage payment is\n (%.2f) " % mortgagePayment)

This mortgage package does it nicely:
>>> import mortgage
>>> m=mortgage.Mortgage(interest=0.0375, amount=350000, months=360)
>>> mortgage.print_summary(m)
Rate: 0.037500
Month Growth: 1.003125
APY: 0.038151
Payoff Years: 30
Payoff Months: 360
Amount: 350000.00
Monthly Payment: 1620.91
Annual Payment: 19450.92
Total Payout: 583527.60

I also watched this youtube video and had the same problem.
I'm a python newbie so bear with me.
The instructors in the video were using python3 and I am using python2
so I am not sure if all the syntax are the same. But using some information found in this thread and info from this link: (http://www.wikihow.com/Calculate-Mortgage-Payments) I was able to get the answer. (My calculations matched an online mortgage calculator)
#!/usr/bin/env python
# The formula I used:
M = L * ((I * ((1+I) ** n)) / ((1+I) ** n - 1))
# My code (probably not very eloquent but it worked)
# monthly payment
M = None
# loan_amount
L = None
# interest rate
I = None
# number of payments
n = None
L = raw_input("Enter loan amount: ")
L = float(L)
print(L)
I = raw_input("Enter interest rate: ")
I = float(I)/100/12
print(I)
n = raw_input("Enter number of payments: ")
n = float(n)
print(n)
M = L * ((I * ((1+I) ** n)) / ((1+I) ** n - 1))
M = str(M)
print("\n")
print("Monthly payment is " + M)

Apparently you copied the formula wrong.
wrong: * numberOfPayments
correct: ** numberOfPayments
note: it appears twice in the formula
note: in python, ** is "to the power of" operator.

This worked pretty well for me. Not exact, as loan calculators usually go by days, and I'm lazy so I go by months but here's a simple one I wrote that is accurate enough to be practical.
L = input("How much will you be borrowing? ")
L = float(L)
print(L)
N = input("How many years will you be paying this loan off? ")
N = float(N) *12
print(N)
I = input("What is the interest in percents that you will be paying? Ex, 10% = 10, 5% = 5, etc. ")
I = float(I)/100
print(I)
M = (L/N) + I*(L/N)
float(M)
print("Your monthly payment will be: ")
print(M)

I also came accross this problem and this is my solution
loan = input('Enter Loan Amount: ')
loan = float(loan)
numberOfPayments = input('Enter Loan payments in years: ')
numberOfPayments = float(numberOfPayments) * 12
interest = input('Annuel interest Rate: ')
interest = float(interest)/100/12
monthlyPayments = loan * (interest * (1 + interest) ** numberOfPayments) / ((1 + interest) ** numberOfPayments - 1)
print (round(monthlyPayments))

Mismatch but don't know what is wrong...(python)

So I need help with programming.
My assignment is this:
Write a program to prompt the user for hours and rate per hour using raw_input to compute gross pay. Award time-and-a-half for the hourly rate for all hours worked above 40 hours. Use 45 hours and a rate of 10.50 per hour to test the program (the pay should be 498.75). You should use raw_input to read a string and float() to convert the string to a number. Do not worry about error checking the user input - assume the user types numbers properly.
I did this:
inp = raw_input ('Enter Hours: ')
hours = float(inp)
inp = raw_input ('Enter Rate: ')
rate = float(inp)
print rate, hours
if hours <= 40 :
pay = hours * rate
else :
pay = rate * 40 + (rate * 1.5 * ( hours - 40 ))
print pay
And it seemed to be okay but when I click on check the code, I enter hours 45, and then rate I tried entering 10.50, 10.5 but every time I get this:
10.5 45.0 ← Mismatch
498.75
The answer 498.75 is correct but I keep getting mismatch there so I cannot finish my assignment. Anyone knows what am i doing wrong?

To print float with your format you should use format string (examples).
So you should change line:
print rate, hours
to:
print("Rate = %.2f, Hours = %.0f" % (rate, hours))
# ^ ^
# | Remove all chars after point (may be you need to change that
# according your task)
# Use to chars after comma (no zeros removing)

By using a function you can do it
def computepay(h,r):
if (h>40) :
pay = (40*r)+(h-40)*1.5*r
else:
pay = (h*r)
return pay
try:
inp = raw_input("Please enter hours: ")
hours=float(inp)
inp = raw_input("Please enter rate: ")
rate= float(inp)
except:
print "Please enter a number as input"
quit()
print computepay(hours,rate)

It seems that print rate, hours produces output which the checking program does not expect, and cannot cope with. Simply comment out that line.

hrs = raw_input("Enter Hours:")
h = float(hrs)
rate = raw_input("Enter rate:")
r = float(rate)
pay = h * r
print pay
This would be the answer to your question #user3578390

4.6 Write a program to prompt the user for hours and rate per hour using input to compute gross pay. Pay should be the normal rate for hours up to 40 and time-and-a-half for the hourly rate for all hours worked above 40 hours. Put the logic to do the computation of pay in a function called computepay() and use the function to do the computation. The function should return a value. Use 45 hours and a rate of 10.50 per hour to test the program (the pay should be 498.75). You should use input to read a string and float() to convert the string to a number. Do not worry about error checking the user input unless you want to - you can assume the user types numbers properly. Do not name your variable sum or use the sum() function.
def computepay(h,r):
if h <= 40:
return h * r
elif h > 40:
return (40 * r + ((h - 40) * 1.5 * r))
hrs = float(input("Enter Hours:"))
rate = float(input("Enter Rate:"))
p = computepay(hrs, rate)
print("Pay",p)

I did this:
hrs = raw_input("Enter Hours:")
h = float(hrs)
rate = raw_input("Enter rate:")
r = float(rate)
pay = h * r
if h <=40:
pay = h * r
else:
pay = r * 40 + (r * 1.5 * ( h - 40 ))
print pay