How to Create a List of Tuples in Python?

In Python, creating a list of tuples is a flexible data structure for storing many items. Tuples are immutable, ordered collections that are suitable for grouping similar items. This tutorial will guide you through this with several examples to build and handle lists of tuples.

Understanding Tuples

Tuples are ordered collections of elements. Lists are mutable collections of elements enclosed in square brackets, that combine with tuples to form a list of tuples. List comprehension gives compact code. It also unpacks and assigns variables to each member necessary for quick access. Nesting tuples within lists combines tuples and lists is done for structured data representation.

Example

# Create a list of tuples containing student records
student_records = [
   ("Atharva Shah", 25, "A"),
   ("Student 2", 21, "B"),
   ("Bob Ross", 23, "A"),
]

# Iterate through the list and display each student's details
for record in student_records:
   name, age, grade = record
   print(f"Name: {name}, Age: {age}, Grade: {grade}")

Create a list of student_records with three tuples representing student details: name, age, and grade. Iterate through the list, unpack each tuple, and print the details using f-string formatting.

Example 2: Using List Comprehension

numbers = [1, 2, 3, 4, 5]
squares = [num ** 2 for num in numbers]
cubes = [num ** 3 for num in numbers]

# Combine lists into a list of tuples
result = list(zip(numbers, squares, cubes))

# Display the list of tuples
print(result) # [(1, 1, 1), (2, 4, 8), (3, 9, 27), (4, 16, 64), (5, 25, 125)]

Start with two lists of integers, squares, and cubes. Apply list comprehension to compute the square and cube of each number. Combine the lists element by element into a list of tuples, generating a new tuple for each set. Using the list function, convert the zip object to a list. Output the tuple list that includes the original integer, square, and cube. Then, make a list of student records that has three tuples reflecting student information: name, age, and grade. Iterate through the list, unpacking each tuple and printing the information in f-string format.

Alternatives

Loop to append tuples to an empty list

data = []
for i in range(1, 6):
   data.append((i, i ** 2))

#[(1, 1), (2, 4), (3, 9), (4, 16), (5, 25)]

Map - Apply a function to each element in a list

numbers = [4, 5]
squares = list(map(lambda x: (x, x ** 2), numbers))

# [(4, 16), (5, 25)]

Combine two lists into a list of tuples with zip()

names = ["Alice", "Bob", "Charlie"]
ages = [25, 30, 22]
person_info = list(zip(names, ages))

# [('Alice', 25), ('Bob', 30), ('Charlie', 22)]

Dynamic values with comprehension

even = [num for num in range(2, 11, 4)]
tuples_with_squares = [(num, num ** 2) for num in even]

# [(2, 4), (6, 36), (10, 100)]

Applications

• Lists of tuples are used to store and manipulate complex information.

• Each tuple corresponds to a row in a database table. Efficient data grouping and management.

• Applied in game development to store information. (Characters, scores, and achievements, for tracking, comparison, and unlocking new levels/prizes).

• Simplified extraction of information.

• Linguistic analysis in natural language processing (NLP).

• They are the basic data structure for arranging and manipulating complicated data.

Conclusion

This guide was all about making lists of tuples in Python for manipulating data. Indexing and slicing are techniques, as are loops for iterating over items. We have also discussed examples of real-world applications (DBMS and scientific data processing). Understanding these principles provides you with the tools to manage complicated data structures and improve your programming abilities.