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arXiv · 2307.06588

On approximation by tight wavelet frames on the field of $p$-adic numbers

S. F. Lukomskii·A. M. Vodolazov
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Abstract

We discuss the problem on approximation by tight step wavelet frames on the field $\mathbb{Q}_p$ of $p$-adic numbers. Let $G_n=\{x=\sum_{k=n}^\infty x_k p^k\}$, $X$ be a set of characters. We define a step function $\lambda({\chi})$ that is constant on cosets ${G}_n^\bot\setminus{G}_{n-1}^\bot$ by equalities $\lambda ({G}_n^\bot\setminus{G}_{n-1}^\bot)=\lambda_n>0$ for which $\sum\frac{1}{\lambda_n}<\infty$. We find the order of approximation of functions $f$ for which $\int_X|\lambda( {\chi})\hat{f}(\chi)|^2d\nu(\chi)<\infty$

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S. F. Lukomskii, A. M. Vodolazov. 2023-07-13. On approximation by tight wavelet frames on the field of $p$-adic numbers. https://arxiv.org/abs/2307.06588

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