Concept

Logarithm of a matrix

Related publications (21)

SPEEDING UP KRYLOV SUBSPACE METHODS FOR COMPUTING f(A)b VIA RANDOMIZATION

This work is concerned with the computation of the action of a matrix function f(A), such as the matrix exponential or the matrix square root, on a vector b. For a general matrix A, this can be done by computing the compression of A onto a suitable Krylov ...

Siam Publications2024

Efficient lattice Green's function method for bounded domain problems

William Curtin, Max Ludwig Hodapp, Ankit Gupta

The lattice Green's function method (LGFM) is the discrete counterpart of the continuum boundary element method and is a natural approach for solving intrinsically discrete solid mechanics problems that arise in atomistic-continuum coupling methods. Here, ...

Wiley2022

DIVIDE-AND-CONQUER METHODS FOR FUNCTIONS OF MATRICES WITH BANDED OR HIERARCHICAL LOW-RANK STRUCTURE\ast

Daniel Kressner, Stefano Massei, Alice Cortinovis

This work is concerned with approximating matrix functions for banded matrices, hierarchically semiseparable matrices, and related structures. We develop a new divide-and-conquer method based on (rational) Krylov subspace methods for performing low-rank up ...

SIAM PUBLICATIONS2022

Fast deterministic and randomized algorithms for low-rank approximation, matrix functions, and trace estimation

Alice Cortinovis

In this thesis we propose and analyze algorithms for some numerical linear algebra tasks: finding low-rank approximations of matrices, computing matrix functions, and estimating the trace of matrices. In the first part, we consider algorithms for building ...

EPFL2022

Spectra of non-regular elements in irreducible representations of simple algebraic groups

Donna Testerman

We study the spectra of non-regular semisimple elements in irreducible representations of simple algebraic groups. More precisely, we prove that if G is a simply connected simple linear algebraic group and φ : G → GL(V ) is a non-trivial irreducible repres ...

2021

On Randomized Trace Estimates for Indefinite Matrices with an Application to Determinants

Daniel Kressner, Alice Cortinovis

Randomized trace estimation is a popular and well-studied technique that approximates the trace of a large-scale matrix B by computing the average of x(T) Bx for many samples of a random vector X. Often, B is symmetric positive definite (SPD) but a number ...

2022

Automatic Dysarthric Speech Detection Exploiting Pairwise Distance-Based Convolutional Neural Networks

Hervé Bourlard, Ina Kodrasi, Parvaneh Janbakhshi

Automatic dysarthric speech detection can provide reliable and cost-effective computer-aided tools to assist the clinical diagnosis and management of dysarthria. In this paper we propose a novel automatic dysarthric speech detection approach based on analy ...

IEEE2021

Validation of the ICRF antenna coupling code RAPLICASOL against TOPICA and experiments

Olivier Sauter, Basil Duval, Stefano Coda, Timothy Goodman, Yves Martin, Jean-Marc Moret, Duccio Testa, Patrick Blanchard, Bruno Marchand, Holger Reimerdes, Benoît Labit, Christian Gabriel Theiler, Cristian Sommariva, Alessandro Pau, Laurie Porte, Federico Alberto Alfredo Felici, Alexander Karpushov, Marc Gruber, Antoine Pierre Emmanuel Alexis Merle, Joan Decker, Umar Sheikh, Cristian Galperti, Yanis Andrebe, Pedro Andres Molina Cabrera, Pierre Jacquot, Lorenzo Anton-Louis Talà, Haomin Sun, Pamela Solange Valdés Undurraga, Andrea Salmi, Pascal Morel, Jose Felix Vega Stavro, Javier García Hernández, Richard Pitts, Yann Camenen, Jan Horacek, Raffaele Tito D'Agnolo, Roland Behn, Marco Wischmeier, Nicola Vianello, Federico Nespoli, Antonio José Pereira de Figueiredo, Alberto Bottino, Doohyun Kim, Emiliano Fable, Ben McMillan, Wouter Vijvers, Patrycja Nowak-Sliwinska, Andrea Scarabosio, Zhouji Huang, Cedric Kar-Wai Tsui, Kevin Henricus Annemarie Verhaegh, Anna Teplukhina, Dávid Wágner, Hoang Bao Le, Diego Carnevale, Claudio Marini, Thomas Binderup Jensen, Heinz Mueller, Donghyun Kim, Jennifer Kaitlyn Olsen, Himank Anand, Xiao Wang, Janir Nuno Ramos Antunes Da Cruz, Attila Bencze, Jose Vicente Sanchez Mut, Bernhard Sieglin, Michael Oliver Reinke, Allan Svejstrup Nielsen, Otto Asunta, Hartmut Zohm, Erwan Fabrice Koch, Ana Susnjara, Emanuele Poli, Matteo Fontana, Stefano Mattei, Gergely Papp, Lenke Horváth, Thomas Riedl, Wen Bin Chng, Giovanni Tardini, Daniel Molina Romero, Telmo David Ribeiro Da Costa, Dahye Choi

In this paper we validate the finite element code RAPLICASOL, which models radiofrequency wave propagation in edge plasmas near ICRF antennas, against calculations with the TOPICA code. We compare the output of both codes for the ASDEX Upgrade 2-strap ante ...

IOP Publishing Ltd2019

Rational Krylov for Stieltjes matrix functions: convergence and pole selection

Stefano Massei

Evaluating the action of a matrix function on a vector, that is

x=f(\mathcal M)v

, is an ubiquitous task in applications. When

\mathcal M

is large, one usually relies on Krylov projection methods. In this paper, we provide effective choices for the pole ...

2019

Method of displaying an image on a see-through display

Sabine Süsstrunk, Adrien Birbaumer, Martinus Bosch

The present invention concerns a method of displaying an image on a see-through display. The method comprises: obtaining (101) a first electromagnetic radiation matrix of an object, the first matrix comprising first matrix elements representing radiation i ...

2019

Daylighting simulation for external Venetian blinds based on HDR sky luminance monitoring with matrix algebraic approach

Jean-Louis Scartezzini, Jérôme Henri Kämpf, Yujie Wu

An accurate daylighting simulation can potentially improve the quality of pre-planing buildings and regulating daylighting to achieve the goal of green buildings. However, standard sky models can hardly reproduce real skies in real-time for a specific loca ...

Elsevier2019

Fast multiscale reconstruction for Cryo-EM

Michaël Unser, Laurène Donati, Masih Nilchian

We present a multiscale reconstruction framework for single-particle analysis (SPA). The representation of three-dimensional (3D) objects with scaled basis functions permits the reconstruction of volumes at any desired scale in the real-space. This multisc ...

Elsevier2018

The Mutual Information in Random Linear Estimation Beyond i.i.d. Matrices

Nicolas Macris, Jean François Emmanuel Barbier, Florent Gérard Krzakala

There has been definite progress recently in proving the variational single-letter formula given by the heuristic replica method for various estimation problems. In particular, the replica formula for the mutual information in the case of noisy linear esti ...

IEEE2018

Unified Theory for Recovery of Sparse Signals in a General Transform Domain

Kyong Hwan Jin

Compressed sensing is provided a data-acquisition paradigm for sparse signals. Remarkably, it has been shown that the practical algorithms provide robust recovery from noisy linear measurements acquired at a near optimal sampling rate. In many real-world a ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2018

Spin polarization and attosecond time delay in photoemission from solids

Mauro Fanciulli

In the photoemission process electrons are emitted from a solid upon excitation with UV light. From the measurement of their energy and momentum, angle-resolved photoemission spectroscopy (ARPES) allows to reconstruct the electronic properties of the solid ...

EPFL2018

Semi-analytical solution of flow to a well in an unconfined-fractured aquifer system separated by an aquitard

David Andrew Barry

Semi-analytical solutions are presented for flow to a well in an extensive homogeneous and anisotropic unconfined-fractured aquifer system separated by an aquitard. The pumping well is of infinitesimal radius and screened in either the overlying unconfined ...

2018

Algebraic and topological methods in combinatorics

Adrian Claudiu Valculescu

The present thesis deals with problems arising from discrete mathematics, whose proofs make use of tools from algebraic geometry and topology. The thesis is based on four papers that I have co-authored, three of which have been published in journals, and o ...

EPFL2017

An experimentalist's guide to the matrix element in angle resolved photoemission

Simon Karl Moser

Angle resolved photoemission spectroscopy (ARPES) is commonly known as a powerful probe of the one-electron removal spectral function in ordered solid state. With increasing efficiency of light sources and spectrometers, experiments over a wide range of em ...

Elsevier Science Bv2017

Solar photovoltaic module

Christophe Ballif, Franz-Josef Haug, Philipp Friedrich Hermann Löper, Philippe Wyss, Josua Andreas Stückelberger

In the present invention a new solar photovoltaic module is proposed comprising a solar cell comprising a silicon layer having a first (1 a) surface and a second surface (1a) opposite to said first surface. The solar cell further comprises a passivating la ...

2017

Localization of Sound Sources in a Room with One Microphone

Pierre Vandergheynst, Hervé Lissek, Helena Peic Tukuljac

Estimation of the location of sound sources is usually done using microphone arrays. Such settings provide an environment where we know the difference between the received signals among different microphones in the terms of phase or attenuation, which enab ...

Spie-Int Soc Optical Engineering2017