Quadrature formulas for rational functions.
Quasianalytic functions in the sense of Bernstein [Book]
Quotienten-Differenzen-Algorithmus: Beweis der Regeln von Rutishauser (Quotient-Difference Algorithm: Proof of Rutishauser's Ru e)
Rational approximation near zero sets of functions.
The paper deals with the relation between global rational approximation and local approximation off the zero set. Also connections with the problem f2 ∈ R(X) ⇒ f ∈ R(X) are studied.
Rational Chebyshev Approximation on the Unit Disk.
Rational interpolants with preassigned poles, theoretical aspects
Let ⨍ be an analytic function on a compact subset K of the complex plane ℂ, and let denote the rational function of degree n with poles at the points and interpolating ⨍ at the points . We investigate how these points should be chosen to guarantee the convergence of to ⨍ as n → ∞ for all functions ⨍ analytic on K. When K has no “holes” (see [8] and [3]), it is possible to choose the poles without limit points on K. In this paper we study the case of general compact sets K, when such a separation...
Rational interpolation: analytical solution.
Rational modules and higher order Cauchy transforms.
Ray sequences of Laurent-type rational functions.
Remarks of the lemma of Nersesyan in complex approximation
Représentation des fonctions par des séries de polynômes
Rigidité des empilements infinis immergés proprement dans le plan et dans le disque
Sequences of differential operators: exponentials, hypercyclicity and equicontinuity
An eigenvalue criterion for hypercyclicity due to the first author is improved. As a consequence, some new sufficient conditions for a sequence of infinite order linear differential operators to be hypercyclic on the space of holomorphic functions on certain domains of are shown. Moreover, several necessary conditions are furnished. The equicontinuity of a family of operators as above is also studied, and it is characterized if the domain is . The results obtained extend or improve earlier work...
Sobre la estabilización robusta para ciertos tipos de sistemas lineales.
In this paper we consider the problem of robust stabilization of systems with complex pole variations. We show that techniques from the complex function field can also be used to treat these cases. In particular the problem is reduced to one of interpolation theory on the disk.
Solving Complex Approximation Problems by Semiinfmite - Finite Optimization Techniques : A Study on Convergence.
Some applications of the theorem on rational approximation in the mean
Some properties of weighted hyperbolic polynomials.
Some remarks on the space .
Spectral approximation for Segal-Bargmann space Toeplitz operators
Let A stand for a Toeplitz operator with a continuous symbol on the Bergman space of the polydisk or on the Segal-Bargmann space over . Even in the case N = 1, the spectrum Λ(A) of A is available only in a few very special situations. One approach to gaining information about this spectrum is based on replacing A by a large “finite section”, that is, by the compression of A to the linear span of the monomials . Unfortunately, in general the spectrum of does not mimic the spectrum of A as...
Stochastic continuity and approximation
This work is concerned with the study of stochastic processes which are continuous in probability, over various parameter spaces, from the point of view of approximation and extension. A stochastic version of the classical theorem of Mergelyan on polynomial approximation is shown to be valid for subsets of the plane whose boundaries are sets of rational approximation. In a similar vein, one can obtain a version in the context of continuity in probability of the theorem of Arakelyan on the uniform...