Search Results - "Jawecki, Tobias"

Computable upper error bounds for Krylov approximations to matrix exponentials and associated φ-functions by Jawecki, Tobias, Auzinger, Winfried, Koch, Othmar

“…An a posteriori estimate for the error of a standard Krylov approximation to the matrix exponential is derived. The estimate is based on the defect (residual)…”
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A study of defect-based error estimates for the Krylov approximation of φ-functions by Jawecki, Tobias

“…Prior recent work, devoted to the study of polynomial Krylov techniques for the approximation of the action of the matrix exponential e t A v , is extended to…”
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Unitarity of some barycentric rational approximants by Jawecki, Tobias, Singh, Pranav

“…The exponential function maps the imaginary axis to the unit circle and for many applications this unitarity property is also desirable from its…”
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Computable upper error bounds for Krylov approximations to matrix exponentials and associated $${\varvec{\varphi }}$$-functions by Jawecki, Tobias, Auzinger, Winfried, Koch, Othmar

“…An a posteriori estimate for the error of a standard Krylov approximation to the matrix exponential is derived. The estimate is based on the defect (residual)…”
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On the restriction to unitarity for rational approximations to the exponential function by Jawecki, Tobias

“…In the present work we consider rational best approximations to the exponential function that minimize a uniform error on a subset of the imaginary axis…”
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The error of Chebyshev approximations on shrinking domains by Jawecki, Tobias

“…Previous works show convergence of rational Chebyshev approximants to the Pad\'e approximant as the underlying domain of approximation shrinks to the origin…”
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Computable upper error bounds for Krylov approximations to matrix exponentials and associated \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\varvec{\varphi }}$$\end{document}φ-functions by Jawecki, Tobias, Auzinger, Winfried, Koch, Othmar

“…An a posteriori estimate for the error of a standard Krylov approximation to the matrix exponential is derived. The estimate is based on the defect (residual)…”
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A review of the Separation Theorem of Chebyshev-Markov-Stieltjes for polynomial and some rational Krylov subspaces by Jawecki, Tobias

“…The accumulated quadrature weights of Gaussian quadrature formulae constitute bounds on the integral over the intervals between the quadrature nodes. Classical…”
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Efficient Magnus-type integrators for solar energy conversion in Hubbard models by Auzinger, Winfried, Dubois, Juliette, Held, Karsten, Hofstätter, Harald, Jawecki, Tobias, Kauch, Anna, Koch, Othmar, Kropielnicka, Karolina, Singh, Pranav, Watzenböck, Clemens

“…Strongly interacting electrons in solids are generically described by Hubbard-type models, and the impact of solar light can be modeled by an additional…”
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Unitary rational best approximations to the exponential function by Jawecki, Tobias, Singh, Pranav

“…Rational best approximations (in a Chebyshev sense) to real functions are characterized by an equioscillating approximation error. Similar results do not hold…”
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A study of defect-based error estimates for the Krylov approximation of $\varphi$-functions by Jawecki, Tobias

“…Prior recent work, devoted to the study of polynomial Krylov techniques for the approximation of the action of the matrix exponential ${\rm e}^{tA}v$, is…”
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Unitarity of some barycentric rational approximants by Jawecki, Tobias, Singh, Pranav

“…The exponential function maps the imaginary axis to the unit circle and, for many applications, this unitarity property is also desirable from its…”
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Computable upper error bounds for Krylov approximations to matrix exponentials and associated $\varphi$-functions by Jawecki, Tobias, Auzinger, Winfried, Koch, Othmar

“…BIT (2019) An a posteriori estimate for the error of a standard Krylov approximation to the matrix exponential is derived. The estimate is based on the defect…”
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Some Aspects on [numerical] Stability of Evolution Equations of Stiff Type; Use of Computer Algebra by Auzinger, Winfried, Jawecki, Tobias, Koch, Othmar, Pukach, Petro, Stolyarchuk, Roksolyana, Weinmuller, Ewa

“…We are dealing with stiffness phenomena in initial value problems for systems of ordinary differential equations. Such problems appear in many physical…”
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Efficient Magnus-type integrators for solar energy conversion in Hubbard models by Auzinger, Winfried, Dubois, Juliette, Held, Karsten, Hofstätter, Harald, Jawecki, Tobias, Kauch, Anna, Koch, Othmar, Kropielnicka, Karolina, Singh, Pranav, Watzenböck, Clemens

“…Strongly interacting electrons in solids are generically described by Hubbardtype models, and the impact of solar light can be modeled by an additional…”
Get full text