<mathematics> A real-valued function modelling the length of a vector. The norm must be homogeneous and symmetric and fulfil the following condition: the shortest way to reach a point is to go straight toward it. Every convex symmetric closed surface surrounding point 0 introduces a norm by means of Minkowski functional; all vectors that end on the surface have the same norm then.
The most popular norm is the Euclidean norm.
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Nearby terms: NorCroft « NORD PL « NORDUnet « norm » normal distribution » normal form » normalisation