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Related papers: A New Formula for the Inverse Wavelet Transform

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The pseudoinverse of a matrix, a generalized notion of the inverse, is of fundamental importance in linear algebra and, thereby, in many different fields. Despite its proven existence, an algorithmic approach is typically necessary to…

Numerical Analysis · Mathematics 2026-01-21 Holger Boche , Adalbert Fono , Gitta Kutyniok

This article presents the numerical verification and validation of several inversion algorithms for V-line transforms (VLTs) acting on symmetric 2-tensor fields in the plane. The analysis of these transforms and the theoretical foundation…

Numerical Analysis · Mathematics 2024-07-04 Gaik Ambartsoumian , Rohit Kumar Mishra , Indrani Zamindar

We present a novel approach to the regression of quantum mechanical energies based on a scattering transform of an intermediate electron density representation. A scattering transform is a deep convolution network computed with a cascade of…

Machine Learning · Computer Science 2016-05-23 Matthew Hirn , Nicolas Poilvert , Stéphane Mallat

Understanding the mechanisms underlying deep neural networks remains a fundamental challenge in machine learning and computer vision. One promising, yet only preliminarily explored approach, is feature inversion, which attempts to…

Computer Vision and Pattern Recognition · Computer Science 2025-08-15 Jan Rathjens , Shirin Reyhanian , David Kappel , Laurenz Wiskott

We introduce a technique for recovering a sufficiently smooth function from its ray transform over a wide class of curves in a general region of Euclidean space. The method is based on a complexification of the underlying vector fields…

Complex Variables · Mathematics 2010-11-17 Nicholas Hoell , Guillaume Bal

Synthetic turbulence models are a useful tool that provide realistic representations of turbulence, necessary to test theoretical results, to serve as background fields in some numerical simulations, and to test analysis tools. Models of 1D…

Fluid Dynamics · Physics 2016-11-15 Francesco Malara , Francesca Di Mare , Giuseppina Nigro , Luca Sorriso-Valvo

We suggest an adaptive sampling rule for obtaining information from noisy signals using wavelet methods. The technique involves increasing the sampling rate when relatively high-frequency terms are incorporated into the wavelet estimator,…

Statistics Theory · Mathematics 2007-06-13 Peter Hall , Spiridon Penev

The inhomogeneous wave equation, triggered by point sources, forms the basis for the most modern computational techniques of seismic inversion. In this work, we propose to transfer the inhomogeneous wave equation into a homogeneous…

Computational Physics · Physics 2022-09-30 Marcos Vinícius Cândido Henriques

The polar wavelet transform (PWT) has been proven to be a powerful mathematical tool for signal and image processing in recent years. Due to the increasing demand for directional representations of signals in engineering, it is impossible…

General Mathematics · Mathematics 2023-12-13 Hui Zhao , Bing-Zhao Li

In this article we provide a fast computational method in order to calculate the Moore-Penrose inverse of singular square matrices and of rectangular matrices. The proposed method proves to be much faster and has significantly better…

Numerical Analysis · Mathematics 2011-02-10 Vasilios N. Katsikis , Dimitrios Pappas , Athanassios Petralias

We review scale-discretized wavelets on the sphere, which are directional and allow one to probe oriented structure in data defined on the sphere. Furthermore, scale-discretized wavelets allow in practice the exact synthesis of a signal…

Information Theory · Computer Science 2013-12-10 J. D. McEwen , P. Vandergheynst , Y. Wiaux

We apply the Hilbert transform to the physics of internal waves in two-dimensional fluids. Using this demodulation technique, we can discriminate internal waves propagating in different directions: this is very helpful in answering several…

Fluid Dynamics · Physics 2015-04-07 Matthieu Mercier , Nicolas Garnier , Thierry Dauxois

The spectral properties of the Ruelle transfer operator which arises from a given polynomial wavelet filter are related to the convergence question for the cascade algorithm for approximation of the corresponding wavelet scaling function.

Functional Analysis · Mathematics 2007-05-23 Ola Bratteli , Palle E. T. Jorgensen

We introduce continuous supersymmetric transformations to manipulate the modal content in systems of optical waveguides, providing a systematic method to design efficient and robust integrated devices such as tapered waveguides,…

Optics · Physics 2019-01-31 G. Queraltó , V. Ahufinger , J. Mompart

When a matrix has a banded inverse there is a remarkable formula that quickly computes that inverse, using only local information in the original matrix. This local inverse formula holds more generally, for matrices with sparsity patterns…

Numerical Analysis · Mathematics 2016-10-06 Gilbert Strang , Shev MacNamara

In this paper we present a novel algorithm for computing a congruence on an inverse semigroup from a collection of generating pairs. This algorithm uses a myriad of techniques from the theories of groups, automata, and inverse semigroups.…

Group Theory · Mathematics 2025-12-08 Luna Elliott , Alex Levine , James D. Mitchell

An index transform, involving the square of Whittaker's function is introduced and investigated. The corresponding inversion formula is established. Particular cases cover index transforms of the Lebedev type with products of the modified…

Classical Analysis and ODEs · Mathematics 2025-04-01 Semyon Yakubovich

An improved inverse simulated annealing method is presented to determine the structure of complex disordered systems from first principles in agreement with available experimental data or desired predetermined target properties. The…

Materials Science · Physics 2014-10-07 Jan H. Los , Silvia Gabardi , Marco Bernasconi , Thomas D. Kühne

We propose a general proximal algorithm for the inversion of ill-conditioned matrices. This algorithm is based on a variational characterization of pseudo-inverses. We show that a particular instance of it (with constant regularization…

Numerical Analysis · Mathematics 2009-04-07 Pierre Maréchal , Aude Rondepierre

The classical Talbot method for the computation of the inverse Laplace transform is improved for the case where the transform is analytic in the complex plane except for the negative real axis. First, by using a truncated Talbot contour…

Numerical Analysis · Mathematics 2014-07-04 Benedict Dingfelder , J. A. C. Weideman
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