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arXiv · 2005.08678

Sign retrieval in shift-invariant spaces with totally positive generator

José Luis Romero
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Abstract

We show that a real-valued function $f$ in the shift-invariant space generated by a totally positive function of Gaussian type is uniquely determined, up to a sign, by its absolute values $\{|f(\lambda)|: \lambda \in \Lambda \}$ on any set $\Lambda \subseteq \mathbb{R}$ with lower Beurling density $D^{-}(\Lambda)>2$.

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José Luis Romero. 2020-05-18. Sign retrieval in shift-invariant spaces with totally positive generator. https://arxiv.org/abs/2005.08678

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