Learning Journal Assignment for Unit 3 (Python) - 2020

learning-journal-unit-3.py

from colorama import Fore

# 1. countdown & countup application
#  ✓  The code of your program.
#  ✓  Output for the following input: a positive number, a negative number, and zero.
#  ✓  An explanation of your choice for what to call for input of zero.

# Count down from a positive number
def countdown(n):
    if n == 0:
        print(Fore.YELLOW + 'Blastoff!')
    else:
        print(n)
        countdown(n - 1)

# Count up from a negative number
def countup(n):
    if n == 0:
        print(Fore.GREEN + 'Blastoff!')
    else:
        print(n)
        countup(n + 1)

# I took some creative license here. I ask for your patience; I do start writing the assignment strictly as asked, but then I just keep going and I don't want to submit just the basics of what is asked.


def main():
    # The below was inspired, but not derived from the reference below (Python Basics, n.d.).
    try:
        starting_count = int(input(Fore.RESET + '\nHow long would you like the countdown to be: '))
        # In the end I decided to add this first condition because it will make for faster code. The others would require a function call and I believe 2 more layers to the stack versus my immediate exit with 0.
        if starting_count == 0:
            print('\n' + Fore.RED + 'No countdown for you....Blastoff!')
        elif starting_count < 0:
            return countup(starting_count)
        else:
            return countdown(starting_count)
    # Error handling if the user inputs a non-binary input
    except:
        print('\n' + Fore.RED + 'You caused an error. Please enter numbers only\n')
        main()



# 2. RuntimeError

def main2():
    # Removed the int() method and now input is a string and not a integer, meaning the program will error at runtime.
    starting_count = input(Fore.RESET + '\nHow long would you like the countdown to be: ')
    if starting_count == 0:
        print('\n' + Fore.RED + 'No countdown for you....Blastoff!')
    elif starting_count < 0:
        return countup(starting_count)
    else:
        return countdown(starting_count)


# Calls main and calls the countdown and countup functions.
# I used a try/except because human input is prone to faults and I wanted to control error management.
if __name__ == "__main__":
    main()
    main2()

# Output demonstrating the runtime error, including the error message.
# Error Message:
# How long would you like the countdown to be: d
# Traceback (most recent call last):
#   File "u3.py", line 62, in <module>
#     main2()
#   File "u3.py", line 52, in main2
#     elif starting_count < 0:
# TypeError: '<' not supported between instances of 'str' and 'int'

# An explanation of the error message.
# The above message is due to the input being a string and not a integer.

# An explanation of how to fix the error.
# add the int() method to convert the input to a number. This doesn't prevent non-binary entries from erroring which is why my original code used a Try/Except block.

# Reference
# Python Basics. (n.d.). Try and Except in Python. Retrieved from: https://pythonbasics.org/try-except/