An endless loop

[Ron Schleimer]

I am writing a program for my beginning program class as a final project. I got it all done, except when I run through a module, it causes an endless loop through the same module. Maybe I need a way to clear the choice () every time it runs.

#This program will help a person keep their budget
totalBudget = 4000

#the main function
def main ():
    print 'Welcome to my personal budget calculator'
    print
    choice ()
    
#this function will start the menu selection
def choice ():
    print 'Menu Selection'
    print '1 - Add an Expense'
    print '2 - Remove an Expense'
    print '3 - Add a Revenue'
    print '4 - Remove a Revenue'
    print '5 - Exit'
    selection = input ('Enter menu selection ')
    while selection  !=5:
        if selection == 1:
            addExpense (totalBudget)
        if selection == 2:
            removeExpense (totalBudget)
        if selection == 3:
            addRevenue (totalBudget)
        if selection == 4:
            removeRevenue (totalBudget)
        if selection == 5:
            print 'Goodbye'
    
#this function will add an expense
def addExpense (totalBudget):
    addAmount = input ('Enter the amount of the expense to be added. ')
    addFrequency = input ('Enter the frequency of the expense. ')
    addTotal = addAmount * addFrequency
    if totalBudget > addTotal:
        totalBudget = totalBudget - addTotal
        print 'The new budget is', totalBudget
        return totalBudget
    elif totalBudget < addTotal:
        print 'The expense exceeds current budget. Try again'
        
    
#this function will remove an expense
def removeExpense (totalBudget):
    removeAmount = input ('Enter the amount of the expense to be removed. ')
    removeFrequency = input ('Enter the frequency of the expense. ')
    removeTotal = removeAmount * removeFrequency
    if removeTotal > totalBudget:
        print 'Expenses exceed the budget. Try again.'
    elif removeTotal < totalBudget:
        totalBudget = totalBudget + removeTotal
        print 'The new budget is', totalBudget
        return totalBudget
      
#this function will add a revenue
def addRevenue (totalBudget):
    addIncome = input ('Enter the amount of the revenue to be added. ')
    totalBudget = addIncome + totalBudget
    print 'Your new budget is', totalBudget
    return totalBudget
   
#this function will remove a revenue
def removeRevenue (totalBudget):
    removeIncome = input ('Enter the amount of the revenue to be removed. ')
    if removeIncome > totalBudget:
        print 'Your income exceeds budget. Try again.'
    elif removeIncome < totalBudget:
        totalBudget = totalBudget - removeIncome
        print 'Your new budget is', totalBudget
        return totalBudget

main()

[Glenton]

Hi. Thanks for posting

The issue is that the selection variable is set at the beginning of choice, and is then never allowed to change again. This is because you then enter into a loop, and the loop goes around and around, but selection never changes!

Adjusting choice as follows would sort you out:

def choice ():
    while True:
        print
        print 'Menu Selection'
        print '1 - Add an Expense'
        print '2 - Remove an Expense'
        print '3 - Add a Revenue'
        print '4 - Remove a Revenue'
        print '5 - Exit'
        selection = input ('Enter menu selection ')
        if selection == 1:
            addExpense (totalBudget)
        if selection == 2:
            removeExpense (totalBudget)
        if selection == 3:
            addRevenue (totalBudget)
        if selection == 4:
            removeRevenue (totalBudget)
        if selection == 5:
            print 'Goodbye'
            break

Good luck!

By the way, I made two other changes that weren't really necessary:
1. I made the loop say "while True:" and then included a break statement. You could easily have stayed with the way you did it ("while selection!-5").
2. I added a print to clear a line at the top of the menu.

The other thing I wanted to say, was that running your code with:

if __name__=="__main__": main()

is better, because then you can import your code without running it (ie get your functions somewhere else, without running the main loop), but if you run this particular script, then it runs as normal.