Python: Find the two closest distinct numbers in a given a list of numbers

Python Programming Puzzles: Exercise-78 with Solution

Write a Python program to find the two closest distinct numbers in a given list of numbers.

Input: 
[1.3, 5.24, 0.89, 21.0, 5.27, 1.3]
Output:
[5.24, 5.27]

Input: 
[12.02, 20.3, 15.0, 19.0, 11.0, 14.99, 17.0, 17.0, 14.4, 16.8]
Output:
[14.99, 15.0]

Visual Presentation:

Sample Solution:

Python Code:

# License: https://bit.ly/3oLErEI

# Define a function named 'test' that takes a list of numbers as input
def test(nums):
    # Sort the unique elements in the list in ascending order
    s = sorted(set(nums))
    
    # Use list comprehension to find pairs of adjacent elements
    # Then, find the pair with the smallest difference
    return min([[a, b] for a, b in zip(s, s[1:])], key=lambda x: x[1] - x[0])

# Example 1
nums1 = [1.3, 5.24, 0.89, 21.0, 5.27, 1.3]
print("List of numbers:", nums1)
print("Two closest distinct numbers in the said list of numbers:")
print(test(nums1))

# Example 2
nums2 = [12.02, 20.3, 15.0, 19.0, 11.0, 14.99, 17.0, 17.0, 14.4, 16.8]
print("\nList of numbers:", nums2)
print("Two closest distinct numbers in the said list of numbers:")
print(test(nums2))

Sample Output:

List of numbers: [1.3, 5.24, 0.89, 21.0, 5.27, 1.3]
Two closest distinct numbers in the said list of numbers:
[5.24, 5.27]

List of numbers: [12.02, 20.3, 15.0, 19.0, 11.0, 14.99, 17.0, 17.0, 14.4, 16.8]
Two closest distinct numbers in the said list of numbers:
[14.99, 15.0]

Flowchart:

Python Code Editor :

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Convert GPAs to letter grades.
Next: Find the largest negative and smallest positive numbers.