Normalized squared Euclidean distance between vectors.
NormalizedSquaredEuclideanDistance[u, v]
NormalizedSquaredEuclideanDistance[{a, b}, {x, y}]
→ ((a - x)^2 + (b - y)^2)/(2*(((-a - b)/2 + a)^2 + ((-a - b)/2 + b)^2 + ((-x - y)/2 + x)^2 + ((-x - y)/2 + y)^2))NormalizedSquaredEuclideanDistance[{1, 2, 3}, {3, 5, 10}]
→ 31/28NormalizedSquaredEuclideanDistance[N[{1, 5, 2, 3, 10}, 50], N[{4, 15, 20, 5, 5}, 50]]
→ 0.88302752293577981651376146788990825688073394495412844036697247706422018348626`49.04429309171878