Inverse Theorems of Approximation

Inverse Theorems of Approximation PDF Author: G. G. Lorentz
Publisher:
ISBN:
Category : Analytic functions
Languages : en
Pages : 34

Book Description
This paper contains several theorems which give a lower estimate for the degree of approximation of functions f of a given class by means of linear compinations a1 g1 + ... + an gn. The distance from f to P is measured in the C- and the L1-norm.

Inverse Theorems on the Best Approximation of Functions of a Complex Variable

Inverse Theorems on the Best Approximation of Functions of a Complex Variable PDF Author: G. P. Safronova
Publisher:
ISBN:
Category :
Languages : en
Pages : 14

Book Description
Results announced without proof by S.M. Lozinskii are transferred to the complex domain. The author considers functions continuous on D and analytic in D, where D is the interior of a Jordan curve formed by a finite number of smooth arcs with non-zero angles at the join points. The method of the proof differs only in insignificant details from that yielding the theorems of Lozinskii. (Author).

Smoothing and Approximation of Functions

Smoothing and Approximation of Functions PDF Author: Harold S. Shapiro
Publisher:
ISBN:
Category : Mathematics
Languages : en
Pages : 152

Book Description


Approximation Theory and Approximation Practice, Extended Edition

Approximation Theory and Approximation Practice, Extended Edition PDF Author: Lloyd N. Trefethen
Publisher: SIAM
ISBN: 1611975948
Category : Mathematics
Languages : en
Pages : 375

Book Description
This is a textbook on classical polynomial and rational approximation theory for the twenty-first century. Aimed at advanced undergraduates and graduate students across all of applied mathematics, it uses MATLAB to teach the field’s most important ideas and results. Approximation Theory and Approximation Practice, Extended Edition differs fundamentally from other works on approximation theory in a number of ways: its emphasis is on topics close to numerical algorithms; concepts are illustrated with Chebfun; and each chapter is a PUBLISHable MATLAB M-file, available online. The book centers on theorems and methods for analytic functions, which appear so often in applications, rather than on functions at the edge of discontinuity with their seductive theoretical challenges. Original sources are cited rather than textbooks, and each item in the bibliography is accompanied by an editorial comment. In addition, each chapter has a collection of exercises, which span a wide range from mathematical theory to Chebfun-based numerical experimentation. This textbook is appropriate for advanced undergraduate or graduate students who have an understanding of numerical analysis and complex analysis. It is also appropriate for seasoned mathematicians who use MATLAB.

Approximation Theorems in Commutative Algebra

Approximation Theorems in Commutative Algebra PDF Author: J. Alajbegovic
Publisher: Springer Science & Business Media
ISBN: 9401127166
Category : Mathematics
Languages : en
Pages : 339

Book Description
Various types of approximation theorems are frequently used in general commutative algebra, and they have been found to be useful tools in valuation theory, the theory of Abelian lattice ordered groups, multiplicative ideal theory, etc. Part 1 of this volume is devoted to the investigation of approximation theorems from a classical point of view. The chapters of this part deal with fields and rings, partly ordered groups, and with multirings and d-groups. Part II investigates approximation theorems from a general, categorical point of view. This part is essentially self-contained and requires only a basic knowledge of category theory and first-order logic. For researchers and graduate students of commutative algebra, category theory, as well as applications of logic.

Inverse and Direct Theorems for Best Uniform Approximation by Polynomials

Inverse and Direct Theorems for Best Uniform Approximation by Polynomials PDF Author: Shayne Waldron
Publisher:
ISBN:
Category : Approximation theory
Languages : en
Pages : 5

Book Description


Approximation with Positive Linear Operators and Linear Combinations

Approximation with Positive Linear Operators and Linear Combinations PDF Author: Vijay Gupta
Publisher: Springer
ISBN: 3319587951
Category : Mathematics
Languages : en
Pages : 193

Book Description
This book presents a systematic overview of approximation by linear combinations of positive linear operators, a useful tool used to increase the order of approximation. Fundamental and recent results from the past decade are described with their corresponding proofs. The volume consists of eight chapters that provide detailed insight into the representation of monomials of the operators Ln , direct and inverse estimates for a broad class of positive linear operators, and case studies involving finite and unbounded intervals of real and complex functions. Strong converse inequalities of Type A in terminology of Ditzian–Ivanov for linear combinations of Bernstein and Bernstein–Kantorovich operators and various Voronovskaja-type estimates for some linear combinations are analyzed and explained. Graduate students and researchers in approximation theory will find the list of open problems in approximation of linear combinations useful. The book serves as a reference for graduate and postgraduate courses as well as a basis for future study and development.

Theory of Uniform Approximation of Functions by Polynomials

Theory of Uniform Approximation of Functions by Polynomials PDF Author: Vladislav K. Dzyadyk
Publisher: Walter de Gruyter
ISBN: 3110208245
Category : Mathematics
Languages : en
Pages : 497

Book Description
A thorough, self-contained and easily accessible treatment of the theory on the polynomial best approximation of functions with respect to maximum norms. The topics include Chebychev theory, Weierstraß theorems, smoothness of functions, and continuation of functions.

Approximation Theory and Methods

Approximation Theory and Methods PDF Author: M. J. D. Powell
Publisher: Cambridge University Press
ISBN: 9780521295147
Category : Mathematics
Languages : en
Pages : 356

Book Description
Most functions that occur in mathematics cannot be used directly in computer calculations. Instead they are approximated by manageable functions such as polynomials and piecewise polynomials. The general theory of the subject and its application to polynomial approximation are classical, but piecewise polynomials have become far more useful during the last twenty years. Thus many important theoretical properties have been found recently and many new techniques for the automatic calculation of approximations to prescribed accuracy have been developed. This book gives a thorough and coherent introduction to the theory that is the basis of current approximation methods. Professor Powell describes and analyses the main techniques of calculation supplying sufficient motivation throughout the book to make it accessible to scientists and engineers who require approximation methods for practical needs. Because the book is based on a course of lectures to third-year undergraduates in mathematics at Cambridge University, sufficient attention is given to theory to make it highly suitable as a mathematical textbook at undergraduate or postgraduate level.

Approximation Theory

Approximation Theory PDF Author: Narenda Govil
Publisher: CRC Press
ISBN: 9780824701857
Category : Mathematics
Languages : en
Pages : 560

Book Description
"Contains the contributions of 45 internationally distinguished mathematicians covering all areas of approximation theory-written in honor of the pioneering work of Arun K. Varma to the fields of interpolation and approximation of functions, including Birhoff interpolation and approximation by spline functions."