Python: Remove the duplicate numbers from a given list of numbers

Last update on April 17 2025 13:01:00 (UTC/GMT +8 hours)

Remove Duplicates from List

Write a Python program to remove duplicate numbers from a given list of numbers.

Sample Solution:

Python Code:

# Define a function named unique_nums that returns a list of numbers occurring only once in the given list (nums).
def unique_nums(nums):
    # Use list comprehension to create a list of numbers that occur exactly once in the input list.
    return [i for i in nums if nums.count(i) == 1]

# Test the function with different lists and print the results.

# Test case 1
nums = [1,2,3,2,3,4,5]
print("Original list of numbers:", nums)
print("After removing the duplicate numbers from the said list:")
print(unique_nums(nums))

# Test case 2
nums = [1,2,3,2,4,5]
print("\nOriginal list of numbers:", nums)
print("After removing the duplicate numbers from the said list:")
print(unique_nums(nums))

# Test case 3
nums = [1,2,3,4,5]
print("\nOriginal list of numbers:", nums)
print("After removing the duplicate numbers from the said list:")
print(unique_nums(nums))

Sample Output:

Original list of numbers: [1, 2, 3, 2, 3, 4, 5]
After removing the duplicate numbers from the said list:
[1, 4, 5]

Original list of numbers: [1, 2, 3, 2, 4, 5]
After removing the duplicate numbers from the said list:
[1, 3, 4, 5]

Original list of numbers: [1, 2, 3, 4, 5]
After removing the duplicate numbers from the said list:
[1, 2, 3, 4, 5]

Explanation:

Here is a breakdown of the above Python code:

• Function definition:
• The code defines a function named "unique_nums()" that returns a list of numbers occurring only once in the given list (nums).
• List comprehension:
• The function uses list comprehension to create a list of numbers (i) from the input list (nums) if the count of that number in the list is equal to 1.
• Test cases:
• The function is tested with different lists, and the results are printed using print(unique_nums(...)).

Visual Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to remove duplicate numbers from a list while preserving the order of elements.
• Write a Python program to filter a list of integers to include only unique values without sorting the list.
• Write a Python program to eliminate duplicates from an array using a set and list comprehension to maintain order.
• Write a Python program to create a new list containing only the unique elements from a given list.

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• Python Basic Exercises Home ↩
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Python Code Editor:

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