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Related papers: Fourier series windowed by a bump function

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For each $f\!:\!\mathbb{R}\to\mathbb{C}$ that is Henstock--Kurzweil integrable on the real line, or is a distribution in the completion of the space of Henstock--Kurzweil integrable functions in the Alexiewicz norm, it is shown that the…

Classical Analysis and ODEs · Mathematics 2025-01-29 Erik Talvila

Truncated Fourier, Gauss, Kummer and exponential sums can be used to factorize numbers: for a factor these sums equal unity in absolute value, whereas they nearly vanish for any other number. We show how this factorization algorithm can…

Quantum Physics · Physics 2011-02-21 A. A. Rangelov

For each $f\in L^p({\mathbb R)}$ ($1\leq p<\infty$) it is shown that the Fourier transform is the distributional derivative of a H\"older continuous function. For each $p$ a norm is defined so that the space Fourier transforms is…

Classical Analysis and ODEs · Mathematics 2025-02-26 Erik Talvila

In this paper, we introduce the fractional Fourier series on the fractional torus and study some basic facts of fractional Fourier series, such as fractional convolution and fractional approximation. Meanwhile, fractional Fourier inversion…

Functional Analysis · Mathematics 2024-07-08 Zunwei Fu , Xianming Hou , Qingyan Wu

By recourse to tempered ultradistributions, we show here that the effect of a q-Fourier transform (qFT) is to map {\it equivalence classes} of functions into other classes in a one-to-one fashion. This suggests that Tsallis' q-statistics…

Mathematical Physics · Physics 2015-07-22 A. Plastino , M. C. Rocca

In this paper we construct directionally sensitive functions that can be viewed as directional time-frequency representations. We call such a sequence a rotational uniform covering frame and by studying rotations of the frame, we derive the…

Functional Analysis · Mathematics 2017-10-20 Wojciech Czaja , Weilin Li

If a function $f:\mathbb{R}\to\mathbb{R}$ can be represented as the sum of $n$ periodic functions as $f=f_1+\dots+f_n$ with $f(x+\alpha_j)=f(x)$ ($j=1,\dots,n$), then it also satisfies a corresponding $n$-order difference equation…

Classical Analysis and ODEs · Mathematics 2013-12-16 Bálint Farkas , Szilárd Révész

We use a noncommutative generalization of Fourier analysis to define a broad class of pseudo-probability representations, which includes the known bosonic and discrete Wigner functions. We characterize the groups of quantum unitary…

Mathematical Physics · Physics 2020-05-19 Sang Jun Park , Cedric Beny , Hun Hee Lee

We study Fourier-Bessel series on a q-linear grid, defined as expansions in complete q-orthogonal systems constructed with the third Jackson q-Bessel function, and obtain sufficient conditions for uniform convergence. The convergence…

Classical Analysis and ODEs · Mathematics 2017-10-25 L. D. Abreu , R. Álvarez-Nodarse , J. L. Cardoso

We introduce a rigorous arithmetic--spectral construction associating planar geometric objects with additive prime factor statistics. Let $\mathrm{sopfr}(n)$ denote the sum of prime factors of $n$, counted with multiplicity, and define the…

General Mathematics · Mathematics 2026-02-17 Dimitris Vartziotis

In this paper, we study the error behavior of the nonequispaced fast Fourier transform (NFFT). This approximate algorithm is mainly based on the convenient choice of a compactly supported window function. Here we consider the continuous…

Numerical Analysis · Mathematics 2021-08-25 Daniel Potts , Manfred Tasche

In this paper we generalize the continuous quaternion windowed Fourier transform called the multivariate two sided continuous quaternion windowed Fourier transform. Using the two sided quaternion Fourier transform we derive several…

Classical Analysis and ODEs · Mathematics 2019-06-21 Kamel Brahim , Emna Tefjeni

In this paper, we define a new transform called the Gabor quaternionic Fourier transform (GQFT), which generalizes the classical windowed Fourier transform to quaternion valued-signals, we give several important properties such as the…

Classical Analysis and ODEs · Mathematics 2019-01-07 Mohammed El Kassimi , Said Fahlaoui

We study Fourier theory on quantum Euclidean space. A modified version of the general definition of the Fourier transform on a quantum space is used and its inverse is constructed. The Fourier transforms can be defined by their Bochner's…

Mathematical Physics · Physics 2011-08-08 Kevin Coulembier

In this paper Fourier transform of multivariate orthogonal polynomials on the simplex is presented. A new family of multivariate orthogonal functions is obtained by using the Parseval's identity and several recurrence relations are derived.

Classical Analysis and ODEs · Mathematics 2021-01-12 Esra Güldoğan-Lekesiz , Rabia Aktaş , Iván Area

A trigonometric series strongly bounded at two points and with coefficients forming a log-quasidecreasing sequence is necessarily the Fourier series of a function belonging to all $L^{p}$ spaces, $1\leq p < \infty$. We obtain new results on…

Classical Analysis and ODEs · Mathematics 2017-04-24 Muharem Avdispahić , Zenan Šabanac

In this work, we are interested by the $q$-Bessel Fourier transform with a new approach. Many important results of this $q$-integral transform are proved with a new constructive demonstrations and we establish in particular the associated…

Classical Analysis and ODEs · Mathematics 2013-02-01 Lazhar Dhaouadi

We consider functions on the lattice generated by the integer powers of $q^2$ for $0<q<1$ and construct the $q$-analog of Fourier transform based on the Jackson integral in the space of distributions on the lattice.

q-alg · Mathematics 2007-05-23 M. Olshanetsky , V. Rogov

Following previous investigations by {\"U}st{\"u}nel [22] about the invertibility of some transformations on the Wiener space, we find some entropic conditions under which a random change of time is invertible on the Poisson space. As a…

Probability · Mathematics 2026-04-02 Laure Coutin , Laurent Decreusefond

We develop an alternative approach to the study of Fourier series, based on the Short-Time-Fourier Transform (STFT) acting on $L_{\nu }^{2}(0,1)$, the space of measurable functions $f$ in ${R}$, square-integrable in $ (0,1)$, and…

Functional Analysis · Mathematics 2024-12-31 L. D. Abreu , F. Luef , M. Ziyat