Metric (mathematics) Updated +Created
A metric is a function that give the distance, i.e. a real number, between any two elements of a space.
A metric may be induced from a norm as shown at: Section "Metric induced by a norm".
Metric space vs normed vector space vs inner product space Updated +Created
TODO examples:
Figure 1.
Hierarchy of topological, metric, normed and inner product spaces
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