Overview and Notes: 3.10 - Lists

Make sure you complete the challenge in the challenges section while we present the lesson!

Add your OWN Notes for 3.10 here:

lists are collections of data
store unlimited data
info can be used with loops and functions
index used to locate an item
most indexes start at 0, pseudocode starts 1

Fill out the empty boxes:

Pseudocode Operation	Python Syntax	Description
aList[i]	aList[i]	Accesses the element of aList at index i
x ← aList[i]	x = aList[i]	Assigns the element of aList at index i to a variable 'x'
aList[i] ← x	aList(i) = x	Assigns the value of a variable 'x' to the element of a List at index i
aList[i] ← aList[j]	aList[i] = aList[j]	Assigns value of aList[j] to aList[i]
INSERT(aList, i, value)	aList.insert(i, value)	value is placed at index i in aList. Any element at an index greater than i will shift one position to the right.
APPEND(aList, value)	aList.append(value)	value is added as an element to the end of aList and length of aList is increased by 1
REMOVE(aList, i)	aList.pop(i) OR aList.remove(value)	Removes item at index i and any values at indices greater than i shift to the left. Length of aList decreased by 1.

Overview and Notes: 3.8 - Iteration

Add your OWN Notes for 3.8 here:

iteration is the repetition of a function
done with loops(for, while)
loops are often used with lists/dictionaries

Homework Assignment

Instead of us making a quiz for you to take, we would like YOU to make a quiz about the material we reviewed.

We would like you to input questions into a list, and use some sort of iterative system to print the questions, detect an input, and determine if you answered correctly. There should be at least five questions, each with at least three possible answers.

You may use the template below as a framework for this assignment.

questions = [
    (1, "What is 2 + 2?", "four", "zero", "one"),
    (3, "What is 6 x 7?", "five", "eight", "forty two"),
    (2, "What is 4 / 4?", "two", "one", "five"),
    (3, "What is 9 - 2?", "five", "two", "seven"),
    (1, "What is 7 squared?", "forty nine", "twenty three", "nine")
]

def questionloop(qlist):
    score = 0
    for sub in qlist:
        print("question: " + sub[1])
        print("answer 1: " + sub[2])
        print("answer 2: " + sub[3])
        print("answer 3: " + sub[4])
        res = input("Choose an answer number: ")
        if int(res) == sub[0]:
            score += 1
            continue
        else:
            continue

    percent = score * 100 / 5
    passfail = ""

    if percent < 70:
        passfail = "failed"
    else:
        passfail = "passed"

    print("You " + str(passfail) + " the test with " + str(percent) + "%.")

questionloop(questions)

question: What is 2 + 2?
answer 1: four
answer 2: zero
answer 3: one
question: What is 6 x 7?
answer 1: five
answer 2: eight
answer 3: forty two
question: What is 4 / 4?
answer 1: two
answer 2: one
answer 3: five
question: What is 9 - 2?
answer 1: five
answer 2: two
answer 3: seven
question: What is 7 squared?
answer 1: forty nine
answer 2: twenty three
answer 3: nine
You failed the test with 40.0%.

Hacks

Here are some ideas of things you can do to make your program even cooler. Doing these will raise your grade if done correctly.

Add more than five questions with more than three answer choices
Randomize the order in which questions/answers are output
At the end, display the user's score and determine whether or not they passed

Challenges

Important! You don't have to complete these challenges completely perfectly, but you will be marked down if you don't show evidence of at least having tried these challenges in the time we gave during the lesson.

3.10 Challenge

Follow the instructions in the code comments.

grocery_list = ['apples', 'milk', 'oranges', 'carrots', 'cucumbers']

# Print the fourth item in the list
print(grocery_list[3])

# Now, assign the fourth item in the list to a variable, x and then print the variable
x = grocery_list[3]
print(x)
# Add these two items at the end of the list : umbrellas and artichokes
grocery_list.append("umbrellas")
grocery_list.append("artichokes")


# Insert the item eggs as the third item of the list 
grocery_list.insert(2,"eggs")

# Remove milk from the list 
grocery_list.remove("milk")

# Assign the element at the end of the list to index 2. Print index 2 to check
grocery_list[2] = grocery_list[6]
print(grocery_list[2])

# Print the entire list, does it match ours ? 
print(grocery_list)

# Expected output
# carrots
# carrots
# artichokes
# ['apples', 'eggs', 'artichokes', 'carrots', 'cucumbers', 'umbrellas', 'artichokes']

carrots
carrots
artichokes
['apples', 'eggs', 'artichokes', 'carrots', 'cucumbers', 'umbrellas', 'artichokes']

3.8 Challenge

Create a loop that converts 8-bit binary values from the provided list into decimal numbers. Then, after the value is determined, remove all the values greater than 100 from the list using a list-related function you've been taught before. Print the new list when done.

Once you've done this with one of the types of loops discussed in this lesson, create a function that does the same thing with a different type of loop.

binarylist = [
    "01001001", "10101010", "10010110", "00110111", "11101100", "11010001", "10000001"
]
newlist = []
def binary_convert(binary):
    dec = 0
    i = 7
    for num in str(binary):
        if int(num) == 1:
            dec += 2**i
            i -= 1
            continue
        else:
            i -= 1
            continue
    newlist.append(dec)

for x in binarylist:
    binary_convert(x)

print(newlist)

for new in newlist:
    if new > 100:
        newlist.remove(new)

print(newlist)

[73, 170, 150, 55, 236, 209, 129]
[73, 150, 55, 209]