Results 21 to 30 of about 282,700 (287)

Rational approximation, II

open access: yesAdvances in Mathematics, 1978
Let \(\pi_m\) denote the class of all real polynomials of degree at most \(m\) and \(\pi_{m,n}\) denote the collection of all rational functions \(r_{m,n}(x)=\frac{p(x)}{q(x)}, p\in\pi_m, q\in\pi_n\). Let \(\lambda_{m,n}\equiv\lambda_{m,n}(f^{-1})=\inf_{r_{m,n}\in\pi_{m,n}}\left\|\frac1{f(x)}-\gamma_{m,n}(x)\right\|_{l_{\infty}[0,\infty]}\) where \(f\),
Erdös, Paul   +2 more
openaire   +1 more source

Generalized Hypergeometric Function 3F2 Ratios and Branched Continued Fraction Expansions

open access: yesAxioms, 2021
The paper is related to the classical problem of the rational approximation of analytic functions of one or several variables, particulary the issues that arise in the construction and studying of continued fraction expansions and their multidimensional ...
Tamara Antonova   +2 more
doaj   +1 more source

Numerical integration for high order pyramidal finite elements [PDF]

open access: yes, 2010
We examine the effect of numerical integration on the convergence of high order pyramidal finite element methods. Rational functions are indispensable to the construction of pyramidal interpolants so the conventional treatment of numerical integration ...
Nigam, Nilima, Phillips, Joel
core   +1 more source

Fast and accurate con-eigenvalue algorithm for optimal rational approximations [PDF]

open access: yes, 2012
The need to compute small con-eigenvalues and the associated con-eigenvectors of positive-definite Cauchy matrices naturally arises when constructing rational approximations with a (near) optimally small $L^{\infty}$ error. Specifically, given a rational
Beylkin, G., Haut, T. S.
core   +1 more source

Detecting and diagnosing faults in dynamic stochastic distributions using a rational b-splines approximation to output PDFs [PDF]

open access: yes, 2003
Describes the process of detecting and diagnosing faults in dynamic stochastic distributions using a rational b-splines approximation to output ...
G. A. Smook   +16 more
core   +1 more source

Rational approximation

open access: yesAdvances in Mathematics, 1976
Several authors have investigated the question of approximating certain functions by reciprocals of polynomials under the uniform norm on the positive real axis. In this paper, the authors survey many of the known results in this direction. They also provide simplified proofs in some cases and obtain several new results as well.
Erdös, Paul, Reddy, A.R
openaire   +1 more source

Non-linear Least-Squares Optimization of Rational Filters for the Solution of Interior Hermitian Eigenvalue Problems

open access: yesFrontiers in Applied Mathematics and Statistics, 2019
Rational filter functions can be used to improve convergence of contour-based eigensolvers, a popular family of algorithms for the solution of the interior eigenvalue problem. We present a framework for the optimization of rational filters based on a non-
Jan Winkelmann, Edoardo Di Napoli
doaj   +1 more source

On the closedness of approximation spectra [PDF]

open access: yes, 2009
Generalizing Cusick's theorem on the closedness of the classical Lagrange spectrum for the approximation of real numbers by rational ones, we prove that various approximation spectra are closed, using penetration properties of the geodesic flow in cusp ...
Parkkonen, Jouni, Paulin, Frédéric
core   +3 more sources

Algebraic Solution of Tropical Best Approximation Problems

open access: yesMathematics, 2023
We introduce new discrete best approximation problems, formulated and solved in the framework of tropical algebra, which deals with semirings and semifields with idempotent addition.
Nikolai Krivulin
doaj   +1 more source

Compressed Passive Macromodeling [PDF]

open access: yes, 2012
This paper presents an approach for the extraction of passive macromodels of large-scale interconnects from their frequency-domain scattering responses. Here, large scale is intended both in terms of number of electrical ports and required dynamic model ...
Grivet-Talocia, S.   +1 more
core   +1 more source

Home - About - Disclaimer - Privacy