Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 4

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: positive linear operator

Sortuj według:

Ogranicz wyniki do:

Multivariate and abstract approximation theory for Banach space valued functions

Anastassiou G. A.

Demonstratio Mathematica

2017

Vol. 50, nr 1

208--222

Here we study quantitatively the high degree of approximation of sequences of linear operators acting on Banach space valued Fréchet differentiable functions to the unit operator, as well as other basic approximations including those under convexity. These operators are bounded by real positive linear companion operators. The Banach spaces considered here are general and no positivity assumption is made on the initial linear operators for which we study their approximation properties. We derive pointwise and uniform estimates, which imply the approximation of these operators to the unit assuming Fréchet differentiability of functions, and then we continue with basic approximations. At the end we study the special case where the approximated function fulfills a convexity condition resulting into sharp estimates. We give applications to Bernstein operators.

Statistical approximation in multivariate modular function spaces

Belen C., Yildirim M.

Commentationes Mathematicae

2011

Vol. 51, [Z] 1

39-53

In this paper, using the concept of A-statistical convergence we prove a Korovkin type approximation theorem in multivariate modular function spaces. Furthermore, giving an example via bivariate operators of Kantorovich type, it is shown that our theorem is stronger than its classical case.

A Korovkin type approximation theorem and its application

Büyükyazici Í.

Fasciculi Mathematici

2010

Nr 45

13-23

In this paper, we investigate a Korovkin-type approximation theorem for sequences of positive linear operators on the space of all continuous real valued functions defined on [a,b]. We also obtain some approximation properties for sequences of positive linear operators constructed by means of the Bernstein operator.

Approximation by bivariate Mazhar-Totik operators

Wachnicki E.

Commentationes Mathematicae

2010

Vol. 50, [Z] 2

141-153

The aim of this paper is to study a bivariate version of the operator investigated in [2], [4]. We shall present Voronovskaya type theorem and theorems giving a rate of convergence of this operator. Some applications for the limit problem are indicated.