Tuples in Python
Python Tuples
In Python, tuples are a built-in data type used to store multiple items in a single variable. Tuples are similar to lists but have some key differences, making them a useful choice in specific situations. This lesson will cover the characteristics of tuples, how to create them, and their usage in Python.
1. What is a Tuple?
A tuple is a collection that is both ordered and unchangeable (immutable). This means that once a tuple is created, you cannot change its contents (i.e., you cannot add, remove, or modify items).
Characteristics of Tuples:
- Ordered: The items in a tuple have a defined order, and that order will not change.
- Unchangeable: Tuples cannot be modified after creation.
- Allow Duplicates: Tuples can contain multiple items with the same value.
Example: Create a Tuple
python
1thistuple = ("apple", "banana", "cherry")
2print(thistuple) # Output: ('apple', 'banana', 'cherry')
2. Tuple Items
Tuple items are indexed, with the first item having index [0]
, the second item having index [1]
, and so forth.
Example: Allowing Duplicate Values
python
1thistuple = ("apple", "banana", "cherry", "apple", "cherry")
2print(thistuple) # Output: ('apple', 'banana', 'cherry', 'apple', 'cherry')
3. Tuple Length
To determine how many items are in a tuple, you can use the len()
function.
Example: Print the Number of Items
python
1thistuple = ("apple", "banana", "cherry")
2print(len(thistuple)) # Output: 3
4. Creating a Tuple with One Item
To create a tuple with only one item, you must include a trailing comma after the item. Without the comma, Python will not recognize it as a tuple.
Example: One Item Tuple
python
1thistuple = ("apple",) # This is a tuple
2print(type(thistuple)) # Output: <class 'tuple'>
3
4# NOT a tuple
5thistuple = ("apple") # This is a string, not a tuple
6print(type(thistuple)) # Output: <class 'str'>
5. Tuple Items - Data Types
Tuple items can be of any data type. You can have tuples containing strings, integers, booleans, and even other tuples.
Example: Different Data Types
python
1tuple1 = ("apple", "banana", "cherry") # Tuple of strings
2tuple2 = (1, 5, 7, 9, 3) # Tuple of integers
3tuple3 = (True, False, False) # Tuple of booleans
4
5# A tuple with mixed data types
6mixed_tuple = ("abc", 34, True, 40, "male")
6. What is the Data Type of a Tuple?
From Python's perspective, tuples are defined as objects with the data type 'tuple'.
Example: Check the Data Type
python
1mytuple = ("apple", "banana", "cherry")
2print(type(mytuple)) # Output: <class 'tuple'>
7. The tuple() Constructor
You can also create a tuple using the tuple()
constructor. This method is useful when you want to create a tuple from an iterable.
Example: Using the tuple() Method
python
1thistuple = tuple(("apple", "banana", "cherry")) # Note the double round-brackets
2print(thistuple) # Output: ('apple', 'banana', 'cherry')