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3 matches

Find k Closest Points to Origin in Python

Sorts a list of (x, y) point tuples by their Euclidean distance from the origin and returns the k nearest points.

import math

def k_closest(points, k):
    points.sort(key=lambda p: math.sqrt(p[0]**2 + p[1]**2))
    return points[:k]

if __name__ == "__main__":
    points = [(1, 2), (3, 4), (-1, 0), (5, 5), (0, 1)]
    k = 3
    result = k_closest(points, k)
    print(f"Original points: {points}")
    print(f"K closest points (k…

12 0 Open

Algorithms & data structures easy

How to Compute Cosine Similarity Between Two Vectors in Python

This code calculates the cosine similarity between two numeric vectors using the dot product and Euclidean norms, returning a value between -1 and 1.

cosine similarity vectors math

Python

import math

def cosine_similarity(vec_a, vec_b):
    if len(vec_a) != len(vec_b):
        raise ValueError("Vectors must have the same length")
    
    dot_product = sum(a * b for a, b in zip(vec_a, vec_b))
    norm_a = math.sqrt(sum(a * a for a in vec_a))
    norm_b = math.sqrt(sum(b * b for b in vec_b))
    
    i…

14 0 Open

Algorithms & data structures easy

Pair Elements with Next Cyclic Neighbor in Python

Create tuples pairing every element with its next element, wrapping around to the first element for the last one.

pairs cyclic list

Python

def cyclic_pairs(lst):
    if not lst:
        return []
    return [(lst[i], lst[(i + 1) % len(lst)]) for i in range(len(lst))]


if __name__ == "__main__":
    sample = [1, 2, 3, 4, 5]
    result = cyclic_pairs(sample)
    print(result)

14 0 Open

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