Python Tuples Explained With Code Samples

In my earlier article, I had covered Python Lists.  In this article, I will be covering Python tuples.

What is a Tuple

Just like a Python list, a tuple is a set of values.  Unlike a List, a tuple is immutable, so you cannot modify it after it is created. Also, the values in a List are enclosed in square brackets, a tuple on the other hand, uses parentheses.

Creating a Tuple

You can create a tuple by specifying comma separated values directly or within parentheses.  The following code demonstrates this:

mytuple1 = (1,"two",2.5,"three")mytuple2 = 1,5,7print(mytuple1)print(mytuple2)

 

As you can see from the code above, a Python tuple can contain values of different data types. The above code creates a tuple mytuple1 that has values of type Integer, Decimal and String. It also creates mytuple2 using simple comma separated values. So this code prints the following output:

(1, 'two', 2.5, 'three')(1, 5, 7)

Accessing values in a Tuple

You can access the values in a tuple via the slice operator. It consists of [] or [:]. You can access Python tuples both in the forward as well as backward direction.  In the forward direction,tuples start from position 0 for the first element in the tuple. In the backward direction, tuples start at position -1 for the last value in the list.

The following code demonstrates this:

mytuple = (2,4,'Hello',10.5,"World")print (mytuple) print(mytuple[2]) print(mytuple[0:2]) print(mytuple[2:]) print(mytuple[:3])print(mytuple[-1])

This code prints the following output:

(2, 4, 'Hello', 10.5, 'World')Hello(2, 4)('Hello', 10.5, 'World')(2, 4, 'Hello')World

Updating a Tuple

As mentioned earlier, a tuple is immutable. So you cannot update a value from a tuple. If you try to update a value in a tuple, an error occurs. The following code demonstrates this:

 

mytuple = ("cat","dog","cow","monkey")mytuple[2] = "horse"print(mytuple)

This code tries to update the value at position 2. So an error occurs as follows:

Traceback (most recent call last):File "tupledemo.py", line 20, in <module>mytuple[2] = "horse"TypeError: 'tuple' object does not support item assignment

Removing a value from a Tuple

You cannot delete an individual value from a tuple. However, you can delete the entire tuple. The following code demonstrates this:

mytuple = ("cat","dog","cow","monkey")del mytupleprint(mytuple)

The above code deletes mytuple and then tries to print it. So it causes an exception as follows:

Traceback (most recent call last):File "tupledemo.py", line 21, in <module>print(mytuple)NameError: name 'mytuple' is not defined

Concatenating Tuples

You can concatenate tuples using the concatenation operator(+ operator). The following code demonstrates this:

mytuple1 = ('apple','orange')mytuple2 = ('banana','mango','cherry')mytuple3 = mytuple1+mytuple2print(mytuple3)

This code concatenates mytuple1 and mytuple2 and creates mytuple3 . So it prints the following output:

('apple', 'orange', 'banana', 'mango', 'cherry')

Using Repetition Operator

You can use the repetition operator(*) with tuples. The following code demonstrates this:

mytuple1 = ('apple','orange')mytuple3 = mytuple1*3;print(mytuple3)

This code creates a new tuple mytuple3 which repeats the contents of mytuple1 3 times. So it prints the following output:

('apple', 'orange', 'apple', 'orange', 'apple', 'orange')

Obtaining length of a tuple

Python has a built-in function len. This returns the length of the object passed in. You can use this function to obtain the length of a tuple. The following code demonstrates this:

mytuple1 = ('apple','orange')print(len(mytuple1))

So this code prints the following output:

2

Further Learning

The Python Masterclass
Everything you need to know about Python
Python for beginners
Python for finance

Conclusion

So in this article, we understood what Python tuples are. We also understood how you can create a tuple, access an element from a tuple, concatenate tuples, use the repetition operator with tuples and obtain the length of a tuple. We also saw that tuples cannot be modified once they are created.

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