Find the tuples containing the given element from a list of tuples in Python

A list can have tuples as its elements. In this article we will learn how to identify those tuples which contain a specific search element from a list of tuples using different methods.

Using List Comprehension with Condition

We can use list comprehension with a conditional statement to filter tuples that contain the target element ?

listA = [('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
test_elem = 'Mon'

# Given list
print("Given list:")
print(listA)
print("Check value:")
print(test_elem)

# Using list comprehension with condition
res = [item for item in listA if item[0] == test_elem]

# printing result
print("The tuples containing the element:")
print(res)

Given list:
[('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
Check value:
Mon
The tuples containing the element:
[('Mon', 3), ('Mon', 2)]

Using filter() with Lambda Function

We can use the filter() function along with a lambda function. The in operator checks for the presence of the element anywhere in the tuple ?

listA = [('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
test_elem = 'Mon'

# Given list
print("Given list:")
print(listA)
print("Check value:")
print(test_elem)

# Using lambda and filter with 'in' operator
res = list(filter(lambda x: test_elem in x, listA))

# printing result
print("The tuples containing the element:")
print(res)

Given list:
[('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
Check value:
Mon
The tuples containing the element:
[('Mon', 3), ('Mon', 2)]

Using a Simple Loop

For better readability, you can use a simple for loop to iterate through the list and check each tuple ?

listA = [('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
test_elem = 'Mon'

# Given list
print("Given list:")
print(listA)
print("Check value:")
print(test_elem)

# Using simple loop
res = []
for item in listA:
    if test_elem in item:
        res.append(item)

# printing result
print("The tuples containing the element:")
print(res)

Given list:
[('Mon', 3), ('Tue', 1), ('Mon', 2), ('Wed', 3)]
Check value:
Mon
The tuples containing the element:
[('Mon', 3), ('Mon', 2)]

Comparison of Methods

Conclusion

Use list comprehension for simple and fast filtering of tuples. The filter() function works well for functional programming approaches, while simple loops offer the best readability for complex conditions.