Machine Learning & AI

Basic

Euclidean Distance (KNN)

Straight-line distance between two points; the default metric for k-nearest neighbours.

Formula

d(\mathbf{p},\mathbf{q}) = \sqrt{\sum_i (p_i-q_i)^2}

Variables

\mathbf{p},\mathbf{q}Two vectors

p_i,q_iComponents

Example

p=(0,0), q=(3,4): d=5

Did You Know?

KNN is a "lazy" learner — it does no training and simply memorises the data.

distance knn clustering

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