Question

Python 3.7 to be used. Just a simple design a program that depends on its own. You should also not need to import anything. No code outside of a function!

Median List Traversal and Exception Handling Create a menu-driven program that will accept a collection of non-negative integers from the keyboard, calculate the mean and median values and display those values on the screen. Your menu should have 6 options 50% below 50% above Add a number to the list/array Display the mean Display the median Print the list/array to the screen 5 1 4 Print the list/array in reverse order 6 Quit Program particulars: Use a list of type int to store the integers entered by the user. There must be error checking on the input integer. If it is negative, the program will print an error message and re-prompt. This process will continue until a non-negative integer is entered. You must use a try-except structure to trap both types of input errors (like letters where numbers should go) and range errors (like -1) There must be error checking on the menu choice entered. If the user enters a choice not on the menu, the program will print an error message, re-display the menu and re-prompt. This process will continue until a valid option val ue is entered. Your solution must be modular. The design of your functions is up to you, but the rules of "highly cohesive" and "loosely coupled" must be followed. Your program should be well-documented. Explain what you're doing in your code. Be sure to include the usual name and assignment notes. Note your program will have to sort your array before you can find the median.

Answer 1

Below is the complete program as per the requirements. It is well explained inside the code using comments.

# function will display the menu
def menu():
    print('\n1. Add a number to the list/array')
    print('2. Display the mean')
    print('3. Display the median')
    print('4. Print the list/array to the screen')
    print('5. Print the list/array in reverse order')
    print('6. Quit')

# function adds a number to list
def add(lst):
    # keep asking until user enters a valid number
    while(True):
        try:
            # ask and read for a number
            num = int(input('Enter the number: '))
            # add the number to list
            lst.append(num)
            # return
            return
        except ValueError:
            # print error message to user and ask to enter again
            print('Invalid Number. Try Again.')
            num = int(input('Enter the number: '))

# function displays the mean
def display(lst):
    # initialize total
    total = 0
    # iterate through each number and add to total
    for n in lst:
        total += n

    # calcualte mean
    mean = total/len(lst)

    # print the mean
    print('Mean:',mean)

# function displays the median
def displayMedian(lst):
    median = 0
    # get sorted list
    lst.sort()

    # size of list
    size = len(lst)

    # median index
    mid = int(size/2)

    # if there are even numbers
    if size % 2 == 0:
        # calculate median by taking average of 2 middle elements
        median = (lst[mid] + lst[mid-1])/2
    else:
        median = lst[mid]

    # print the median
    print('Median:',median)
      
# function prints list to the screen
def printList(lst):
    print(lst)

# function prints list in reverse order
def printReverse(lst):
    # get reverse sorted list
    reverse = sorted(lst, reverse=True)

    # print reverse sorted list
    print(reverse)

# main function
def main():
    # initialize the choice
    choice = 0

    # declare a list
    lst = []

    # read menu choice
    # keep asking until user enters a valid choice
    while(True):
        try:
            # display the menu
            menu()
            # ask and read for a number
            choice = int(input('Enter your choice [1-6]: '))

            if choice == 1:
                add(lst)
            elif choice == 2:
                display(lst)
            elif choice == 3:
                displayMedian(lst)
            elif choice == 4:
                printList(lst)
            elif choice == 5:
                printReverse(lst)
            elif choice == 6:
                break;
            else:
                print('Invalid Choice. Try Again.')
          
       except ValueError:
            # print error message to the user and ask to enter again
            print('Invalid Choice. Try Again.')
          
# call the main function
main()

Below is the screenshot of code, in case if indentation is an issue:

function will display the menu def menu (): print \nl. Add a number to the list/array') print 2. Display the mean') print('3. Display the median') print 4. Print the list/array to the screen') print 5. Print the list/array in reverse order') print('6. Quit') function adds a number to list def add (lst): keep asking until user enters a valid number while (True) try: #ask and read for a number int (input ('Enter the number ')) num = # add the number to list 1st.append (num) # return return except ValueError: print error message to user and ask to enter again print 'Invalid Number. Try Again.') num int (input ('Enter the number: ') ) # function displays the mean def display (lst) initialize total total = 0 iterate through each number and add to total for nin lst: total += n # calcualte mean total/len (lst) mean = # print the mean print ('Mean:',mean)

function displays the median def displayMedian (lst) median 0 get sorted list 1st.sort () # size of list len (1st) size= #median index int (size/2) mid if there are even numbers if size 2 =0: calculate median by taking average of 2 middle (1st [mid] lst [mid-11)/2 elements median else 1st [mid] median = print the median print Median:',median) function prints list to the screen def printList (lst): print (1st) function prints list in reverse order def printReverse (1st): get reverse sorted list reverse = sorted (lst, reverse-True) # print reverse sorted list print (reverse)

#main function def main () initialize the choice choice 0 # declare a list lst # read menu choice # keep asking until user enters a valid choice while (True): try: display the menu menu () ask and read for a number choice int (input ('Enter your choice [l-6] ')) if choice 1: add (1st) elif choice = 2: display (lst) elif choice == 3: displayMedian (lst) elif choice 4: printList lst) elif choice == 5 printReverse (lst) elif choice = 6: break else print 'Invalid Choice. Try Again. ) except ValueError: # print error message to user and ask to enter again print 'Invalid Choice. Try Again.') call main function main

Below is the sample output:

1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-61: 1 Enter the number: 54 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-61 1 Enter the number: 83 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-6]: 1 Enter the number: 12 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-61 2 Mean 49.666666666666664

1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-6]: 3 Median: 54 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-6] 4 [12, 54, 83] 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Quit Enter your choice [1-6] 5 [83, 54, 12] 1. Add a number to the list/array 2. Display the mean 3. Display the median 4. Print the list/array to the screen 5. Print the list/array in reverse order 6. Ouit Enter your choice [1-61: 6

This completes the requirement. Let me know if you have any queries.

Thanks!