Get the First Element of a Tuple in Python

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How to get the first element of a tuple in Python? In Python, tuples are ordered collections of elements, and you can access individual elements of a tuple using index notation. To get the first element of a tuple, you can use indexing. In Python, tuples are zero-indexed, which means that the first element is at index 0.

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You can get the first element of a tuple using many ways, for example, by using indexing notation [0], list comprehension, for loop, map() & operator.itemgetter(), zip(), and map() with lambda expression. In this article, I will explain how to get the first element of a tuple by using all these functions with examples.

1. Quick Examples of Getting the First Element of a Tuple

If you are in a hurry, below are some quick examples of getting the first element of a tuple.


# Quick examples of the first element of a tuple

# Example 1: Get the first element of a tuple
tuples = (2, 5, 8)
first_element = tuples[0]

# Example 2: Get the first element of a tuple
tuples = ('Python','Pandas','Java','Hadoop')
first_element = tuples[0]

# Example 3: Get first element in list of tuples
# Using  list comprehension
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
first_element = [x[0] for x in list_tuples]

# Example 4: Use a For Loop 
first_element = []
for tup in list_tuples:
    first_element.append(tup[0])

# Example 5: Using map() and operator.itemgetter() functions
first_element =map(itemgetter(0), list_tuples)

# Example 6: Using zip() function
first_element = list(zip(*list_tuples))[0]

# Example 7: Using map() with lambda expression
first_element = map(lambda x: x[0], list_tuples)

2. Get the First Element of a Tuple

In Python, You can use index notation [0] to get the first element of a tuple. For example, you can create a tuple called tuples containing the integers 2, 5, and 8. Then you can use indexing to get the element at the index 0, which is the first element of the tuple, and assign it to the variable first_element. Finally, you can print the value of first_element, which is 2. 


# Initialization tuple
tuples = (2, 5, 8)
print("Orginal tuples: ",tuples)

# Get the first element of a tuple
first_element = tuples[0]
print("Get the first element of a tuple:", first_element)

Yields below output.

python tuple get first

To get the first element from a tuple of strings in Python, you can use the same indexing notation [0] that you would use for any other type of tuple. For example, you can define a tuple called tuples with four elements. Then you can use indexing to get the first element of the tuple, which is Python, and assign it to the variable first_element. 


# Initialization tuple
tuples = ('Python','Pandas','Java','Hadoop')
print("Orginal tuples: ",tuples)

# Get the first element of a tuple
first_element = tuples[0]
print("Get the first element of a tuple:", first_element)

Yields below output.

python tuple get first

3. Get the First Element of the List of Tuples

You can also use list comprehension to get the first element of each tuple in a list of tuples. For instance, you can define a list of tuples list_tuples containing three tuples. Then you can use list comprehension to extract the first element of each tuple and create a new list called first_element.

The syntax x[0] refers to the first element of each tuple and for x in list_tuple indicates that you want to perform this operation on each tuple in list_tuples. Finally, you can print the result list, which contains the first elements of each tuple in list_tuples. 


# Initialize the list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ", list_tuples)

# Get first element in list of tuples
# Using  list comprehension
first_element = [x[0] for x in list_tuples]
print("Get first element in list of tuples:", first_element)

Yields below output.

python tuple get first

4. Get the First Element in the List of Tuples Using a For Loop

You can also use a for loop to iterate through a list of tuples and append the first element of each tuple to a new list. For example, you can define a list of tuples list_tuples containing three tuples and also, creating an empty list first_element to store the first elements of each tuple.

Then you can use a for loop to iterate through each tuple in list_tuples. Within the loop, you can use indexing tup[0] to access the first element of each tuple, and first_element.append() to add it to the first_element list.


# Initialize the list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ", list_tuples)

# Use a For Loop & get the first element
first_element = []

for tup in list_tuples:
    first_element.append(tup[0])
print("Get first element in list of tuples:", first_element)

Yields the same output as above.

5. Using map() and operator.itemgetter() Functions

You can also use the map() function with operator.itemgetter() function are powerful tool in Python for working with collections of data, such as lists of tuples. For example, first, import the itemgetter() function from the operator module. Then can define a list of tuples called list_tuples containing three tuples.

To extract the first element of each tuple, you can use map() with the itemgetter(0) function as the first argument, which returns a new collection containing the first element of each tuple in list_tuples. Then you can convert the result to a list using the list() function.


from operator import itemgetter

# Initialize the list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ", list_tuples)

# Using map() and operator.itemgetter() functions
first_element =map(itemgetter(0), list_tuples)
print("Get first element in list of tuples:", list(first_element))

Yields the same output as above.

6. Get the First Element Using the zip() Function

To get the first element in the list of tuples use the zip() function. For example, you have a list of tuples called list_tuples that contains two elements in each tuple, a string representing a technology name and an integer representing its fees.

You can use the zip() function to transpose the list of tuples so that you have a tuple of technology names and a tuple of fees, and then you use indexing notation [0] to get the first element of the tuple of technology names.


# list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ", list_tuples)

# Using zip() function
first_element = list(zip(*list_tuples))[0]
print("Get first element in list of tuples:", first_element)

# Output
# Orginal list of tuples:  [('Python', 2000), ('Spark', 2500), ('Pandas', 3000)]
# Get first element in list of tuples: ('Python', 'Spark', 'Pandas')

7. Using map() with Lambda Expression

To get the first element in the list of tuples use map() along with a lambda expression. For instance, a list of tuples called list_tuples is defined with each tuple containing two elements, a string representing a technology name and an integer representing its fees.

A lambda function is defined to extract the first element of each tuple. This lambda function is then used with the map() function to apply it to each element of list_tuples and create a new iterable called first_element which contains the first element of each tuple.


# list of tuples
list_tuples = [("Python", 2000), ("Pandas", 2500), ("Java", 3000)]
print("Orginal list of tuples: ", list_tuples)

# Using map() with lambda expression
first_element = map(lambda x: x[0], list_tuples)
print("Get first element in list of tuples:", list(first_element))

# Output:
# Orginal list of tuples:  [('Python', 2000), ('Pandas', 2500), ('Java', 3000)]
# Get first element in list of tuples: ['Python', 'Pandas', 'Java']

Conclusion

In this article, I have explained how to get the first element of a tuple in Python by using the indexing notation [0], list comprehension, for loop, map() & operator.itemgetter(), zip(), and map() with lambda expressions. Also explained how to get the first element of a list of tuples with examples.

Happy Learning !!

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