Magnitude is an invariant of metric spaces, defined for finite and compact metric spaces. The observed metric space is often considered alongside the family of its dilations, yielding the magnitude function. The limit of the magnitude function as the space is shrunk completely is equal to 1 for some classes of spaces - e.g. the ones embeddable into $\mathbb{R}^n$ with the 1-norm or the Euclidean norm. This is referred to as the space having the one-point property. For spaces lacking the one-point property, the limit in question can be any real number greater than 1.
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