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arXiv · 1912.04340

A note on functions preserving positive definiteness

Piotr Niemiec
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Abstract

The aim of the paper is to give a full characterization of functions f from I into the real line R (where I is an interval in R that satisfies certain natural conditions) such that for any I-valued positive definite kernel K defined on an arbitrary set X the kernel formed by composing f with K is positive definite as well.

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Piotr Niemiec. 2019-12-09. A note on functions preserving positive definiteness. https://arxiv.org/abs/1912.04340

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