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Euclidean Distance

Euclidean distance (L2 distance) is the straight-line distance between two vectors in n-dimensional space, computed as the square root of the sum of squared differences.

What is Euclidean Distance?

Euclidean distance (L2 distance) is the straight-line distance between two vectors in n-dimensional space, computed as the square root of the sum of squared differences.

Euclidean distance (L2 distance) is the straight-line distance between two vectors in n-dimensional space, computed as the square root of the sum of squared differences.

Where is it used?

FAISS `IndexFlatL2` and `sklearn.neighbors.NearestNeighbors(metric='euclidean')` use L2; some image embedding models (CLIP variants) are trained with L2-based contrastive loss.

How to build it

Use `torch.cdist(a.unsqueeze(0), b.unsqueeze(0))` or `np.linalg.norm(a-b)`; in FAISS, `IndexFlatL2` returns squared L2 distances, so compare without sqrt for ranking.