Tuple indexing and slicing in Python - Mini Project: Build & Apply

Tuple indexing and slicing

📖 Scenario: You are organizing a list of your favorite fruits stored in a tuple. You want to practice how to get specific fruits or groups of fruits from this tuple using indexing and slicing.

🎯 Goal: Learn how to access single items and slices from a tuple using indexing and slicing.

📋 What You'll Learn

Create a tuple with exact fruit names

Create variables for index positions

Use tuple indexing and slicing

Print the results

💡 Why This Matters

🌍 Real World

Tuples are used to store fixed collections of items like days of the week, colors, or menu options.

💼 Career

Understanding tuple indexing and slicing helps in data processing, filtering lists, and working with fixed data sets in many programming jobs.

1

Create a tuple of fruits

Create a tuple called fruits with these exact items in order: 'apple', 'banana', 'cherry', 'date', 'elderberry', 'fig', 'grape'.

Python

# Your code here

Hint

Remember, tuples use parentheses and commas between items.

2

Set index variables

Create two variables: first_index set to 0 and last_index set to 4.

Python

fruits = ('apple', 'banana', 'cherry', 'date', 'elderberry', 'fig', 'grape')
# Your code here

Hint

Variables hold numbers to use for indexing later.

3

Use indexing and slicing on the tuple

Create a variable first_fruit that gets the fruit at first_index from fruits. Then create a variable some_fruits that slices fruits from first_index up to but not including last_index.

Python

fruits = ('apple', 'banana', 'cherry', 'date', 'elderberry', 'fig', 'grape')
first_index = 0
last_index = 4
# Your code here

Hint

Use square brackets for indexing and slicing.

4

Print the results

Print first_fruit and then print some_fruits on separate lines.

Python

fruits = ('apple', 'banana', 'cherry', 'date', 'elderberry', 'fig', 'grape')
first_index = 0
last_index = 4
first_fruit = fruits[first_index]
some_fruits = fruits[first_index:last_index]
# Your code here

Hint

Use two print statements, one for each variable.

Practice

1.

What does my_tuple[2] return if my_tuple = (10, 20, 30, 40)?

easy

A. 30

B. 20

C. 40

D. 10

Solution

1. Step 1: Understand tuple indexing

   Indexing starts at 0, so index 2 means the third item in the tuple.

2. Step 2: Identify the item at index 2

   The tuple is (10, 20, 30, 40), so the item at index 2 is 30.

3. Final Answer:

   30 -> Option A

4. Quick Check:

   Index 2 in tuple = 30 [OK]

Hint: Remember: indexing starts at zero in tuples [OK]

Common Mistakes:

• Counting from 1 instead of 0
• Confusing index 2 with index 3
• Mixing up tuple with list indexing

2.

Which of the following is the correct syntax to get the last item of a tuple t?

easy

A. t[1]

B. t[-1]

C. t[last]

D. t[len(t)]

Solution

1. Step 1: Recall negative indexing in tuples

   Negative index -1 accesses the last item in a tuple.

2. Step 2: Check each option

   t[-1] correctly accesses the last item. t[1] accesses second item, t[last] is invalid syntax, t[len(t)] causes IndexError because indexing starts at 0.

3. Final Answer:

   t[-1] -> Option B

4. Quick Check:

   Last item index = -1 [OK]

Hint: Use -1 to get last item from any tuple [OK]

Common Mistakes:

• Using len(t) as index (out of range)
• Trying to use variable 'last' as index
• Confusing positive and negative indexes

3.

What is the output of this code?

t = (5, 10, 15, 20, 25)
print(t[1:4])

medium

A. (10, 15, 20)

B. (10, 15, 20, 25)

C. (5, 10, 15)

D. (15, 20, 25)

Solution

1. Step 1: Understand slicing syntax

   Slicing t[1:4] means start at index 1 up to but not including index 4.

2. Step 2: Extract the slice from the tuple

   Tuple is (5, 10, 15, 20, 25). Index 1 is 10, index 2 is 15, index 3 is 20. Index 4 (25) is excluded.

3. Final Answer:

   (10, 15, 20) -> Option A

4. Quick Check:

   Slicing excludes end index [OK]

Hint: Slice excludes the end index, so stop before it [OK]

Common Mistakes:

• Including the end index in slice
• Confusing indexes with values
• Using parentheses instead of brackets for slicing

4.

Find the error in this code:

t = (1, 2, 3, 4, 5)
print(t[5])

medium

A. Prints 5

B. SyntaxError

C. IndexError: tuple index out of range

D. Prints 1

Solution

1. Step 1: Check tuple length and indexing

   Tuple has 5 items indexed 0 to 4. Index 5 is outside this range.

2. Step 2: Understand what happens when accessing invalid index

   Accessing t[5] causes an IndexError because the index is out of range.

3. Final Answer:

   IndexError: tuple index out of range -> Option C

4. Quick Check:

   Index must be less than length [OK]

Hint: Index must be less than tuple length [OK]

Common Mistakes:

• Using index equal to length
• Confusing SyntaxError with IndexError
• Assuming last index is length instead of length-1

5.

Given t = (2, 4, 6, 8, 10, 12), which expression returns a tuple with every second item starting from the last item going backwards?

hard

A. t[1::2]

B. t[::2]

C. t[-2::-1]

D. t[::-2]

Solution

1. Step 1: Understand slicing with negative step

   A negative step means slicing backwards. t[::-2] starts from the end and takes every second item backwards.

2. Step 2: Check what t[::-2] returns

   Tuple is (2,4,6,8,10,12). t[::-2] picks 12 (last), 8, 4, resulting in (12, 8, 4).

3. Final Answer:

   t[::-2] -> Option D

4. Quick Check:

   Negative step slices backwards skipping items [OK]

Hint: Use negative step in slice to go backwards [OK]

Common Mistakes:

• Using positive step for backward slicing
• Starting slice incorrectly
• Confusing slice start and step positions