Big Idea 1 'Identifying and Correcting Errors'
Practice with identifying and correcting code blocks
alphabet = "abcdefghijklmnopqrstuvwxyz"
alphabetList = []
for i in alphabet:
alphabetList.append(i)
print(alphabetList)
The intended outcome is to determine where the letter is in the alphabet using a while loop
- What is a good test case to check the current outcome? Why?
- Make changes to get the intended outcome.
letter = input("What letter would you like to check?")
i = 0
while i < 26:
if alphabetList[i] == letter:
print("The letter " + letter + " is the " + str(i) + " letter in the alphabet")
i += 1
The intended outcome is to determine where the letter is in the alphabet using a for loop
- What is a good test case to check the current outcome? Why?
- Make changes to get the intended outcome.
letter = input("What letter would you like to check?")
for i in alphabetList:
count = 0
if i == letter:
print("The letter " + letter + " is the " + str(count) + " letter in the alphabet")
count += 1
This code outputs the even numbers from 0 - 10 using a while loop.
- Analyze this code to determine what can be changed to get the outcome to be odd numbers. (Code block below)
evens = []
i = 0
while i <= 10:
evens.append(i)
i += 2
print(evens)
This code should output the odd numbers from 0 - 10 using a while loop.
odds = []
i = 0
while i <= 10:
odds.append(i)
i += 2
print(odds)
This code outputs the even numbers from 0 - 10 using a for loop.
- Analyze this code to determine what can be changed to get the outcome to be odd numbers. (Code block below)
numbers = [0,1,2,3,4,5,6,7,8,9,10]
evens = []
for i in numbers:
if (numbers[i] % 2 == 0):
evens.append(numbers[i])
print(evens)
This code should output the odd numbers from 0 - 10 using a for loop.
numbers = [0,1,2,3,4,5,6,7,8,9,10]
odds = []
for i in numbers:
if (numbers[i] % 2 == 0):
odds.append(numbers[i])
print(odds)
The intended outcome is printing a number between 1 and 100 once, if it is a multiple of 2 or 5
- What values are outputted incorrectly. Why?
- Make changes to get the intended outcome.
numbers = []
newNumbers = []
i = 0
while i < 100:
numbers.append(i)
i += 1
for i in numbers:
if numbers[i] % 5 == 0:
newNumbers.append(numbers[i])
if numbers[i] % 2 == 0:
newNumbers.append(numbers[i])
print(newNumbers)
Challenge
This code segment is at a very early stage of implementation.
- What are some ways to (user) error proof this code?
- The code should be able to calculate the cost of the meal of the user
Hint:
- write a “single” test describing an expectation of the program of the program
- test - input burger, expect output of burger price
- run the test, which should fail because the program lacks that feature
- write “just enough” code, the simplest possible, to make the test pass
Then repeat this process until you get program working like you want it to work.
menu = {"burger": 3.99,
"fries": 1.99,
"drink": 0.99}
total = 0
#shows the user the menu and prompts them to select an item
print("Hello! Welcome to our Python restaurant! What would you like?")
print("Menu")
for k,v in menu.items():
print(k + " $" + str(v)) #why does v have "str" in front of it?
#ideally the code should prompt the user multiple times
order = True
while order:
item = input("Please select an item from the menu")
if item in menu.keys():
total+= menu[item]
print(total)
else:
order = False
#code should add the price of the menu items selected by the user
print("Have a nice day!")
Hacks
Now is a good time to think about Testing of your teams final project...
- What errors may arise in your project?
- What are some test cases that can be used?
- Make sure to document any bugs you encounter and how you solved the problem.
- What are “single” tests that you will perform on your project? Or, your part of the project?
- As Hack Design and Test plan action … Divide these “single” tests into Issues for Scrum Board prior to coding. FYI, related tests could be in same Issue by using markdown checkboxes to separate tests.