ON LAGRANGE INTERPOLATION FOR |X|~α (0 < α < 1)

We study the optimal order of approximation for |x|α (0 < α < 1) by Lagrange interpolation polynomials based on Chebyshev nodes of the first kind. It is proved that the Jackson order of approximation is attained.     

ON LAGRANGE INTERPOLATION TO |x|α(1 ＜α＜ 2) WITH EQUALLY SPACED NODES

S.M. Lozinskii proved the exact convergence rate at the zero of Lagrange interpolation polynomials to |x| based on equidistant nodes in [-1, 1]. In 2000, M. Rever generalized S.M. Lozinskii's result to |x|α(0 ≤α≤ 1). In this paper we will present the exact rate of convergence at the point zero for the interpolants of |x|α(1 ＜α＜ 2)..     

ON LAGRANGE INTERPOLATION FOR |X|~α (0 &lt; α &lt; 1)

We study the optimal order of approximation for |x|α (0 &lt; α &lt; 1) by Lagrange interpolation polynomials based on Chebyshev nodes of the first kind. It is proved that the Jackson order of approximation is attained.     

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|α (2＜α＜4) AT EQUIDISTANT NODES

It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to |x| at equally spaced nodes in [-1, 1] diverges everywhere, except at zero and the end-points. In the present paper, we prove that the sequence of Lagrange interpolation polynomials corresponding to |x|α(2 ＜α＜ 4) on equidistant nodes in [-1,1] diverges everywhere, except at zero and the end-points.     

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|~a

This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the function f(x) =|x|~a(1相似文献   

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|α

This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the function f(x) = |x|α(1 ＜α＜ 2) on [-1, 1] can diverge everywhere in the interval except at zero and the end-points.     

ON LAGRANGE INTERPOLATION TO |x|α(1 < α < 2) WITH EQUALLY SPACED NODES

S.M.Lozinskii proved the exact convergence rate at the zero of Lagrange interpolation polynomials to |x| based on equidistant nodes in [-1,1]. In 2000, M. Rever generalized S.M.Lozinskii's result to |x|α(0 <≤ α≤ 1). In this paper we will present the exact rate of convergence at the point zero for the interpolants of |x|α1(1 < α < 2)..     

ON THE ORDER OF APPROXIMATION FOR THE RATIONAL INTERPOLATION TO |x|

The order of approximation for Newman-type rational interpolation to |x| is studied in this paper. For general set of nodes, the extremum of approximation error and the order of the best uniform approximation are estimated. The result illustrates the general quality of approximation in a different way. For thespecial case where the interpolation nodes are xi= (i/n)(i= 1,2,…,n;r>0) , it is proved that the exact order of approximation is O(1/n),O(1/nlogn) and O(1/n), respectively, corresponding to O1.     

ON BIRKHOFF INTERPOLATION (0;2) CASE

P. Turan and his associates considered in detail the problem of (0.2) interpolation based on the zeros of πn(x). Motivated by these results and an earlier result of Szabados and Varma[9] here we consider the problem of existence, uniqueness and explicit representation of the interpolatory polynomial Rn (x) satisfying the function values at one set of nodes and the second derivative on the other set of nodes. It is important to note that this problem has a unique solution provided these two sets of nodes are chosen properly. We also promise to have an interesting convergence theorem in the second paper of this series, which will provide a solution to the related open problem of P. Turan.     

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR ｜x｜^α

This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the rune tion f（z） =｜x｜^α（1〈α〈2） on [-1,1] can diverge everywhere in the interval except at zero and the end-points.     

ON FUNDAMENTAL SOLUTIONS FOR MULTIVARIATE SINGULAR INTERPOLATION

The objective of this paper is to give a constructive approach to the solution of the fundamental functions for cardinal interpolation from a shift-invariant space generated by the (multi-)integer translates of some compactly supported function whose polynomial symbol has a non-empty zero set.This problem was first introduced by Chut,Diamond,and Raphael,where explicit solutions were given for various zero sets.Later,de Boor,Hollig,and Riemenschneider gave an existence proof for zero sets which are more general.In this pa-per,we give an integral representation of the fundamental solutions that can be made explicit in some cases and we will also give a growth condition of such fundamental solutions.The four-directional box splines will be used as an illustrative example.     

THE EXACT CONVERGENCE RATE AT ZERO OF LAGRANGE INTERPOLATION POLYNOMIAL TO |x|α

In this paper we present a generalized quantitative version of a result due to M. Revers concerning the exact convergence rate at zero of Lagrange interpolation polynomial to f(x) = |x|α with on equally spaced nodes in [-1, 1].     

A NOTE ON LAGRANGE INTERPOLATION OF FUNCTIONS OF GENERALIZED BOUNDED VARIATION

In this paper we solve a remained problem in[2],whether the following estimate approximation for theclass f∈C[-1,1]∩BV by Lagrange interpolation based on the Jacobi abscissasi,L_n~(α,β)(f,x)-f(x)=Ο(1/n)holds,ifα≠β≥-1.     

ON THE FUNDAMENTAL FUNCTION FOR CARDINAL L-SPLINE INTERPOLATION

§1 IntroductionFor any set T={t_j}~n_(j=0) of n+1 real numbers, we consider theconstant coefficient differential operator L_(n+1) (D)=multiply from j=0 to n (D-t_j),D=d/dx and denote by S_n(T) the collection of all functions S∈     

ON A PROBLEM OF (0,2)INTERPOLATION

1. IntroductionGiven n points' in[-1,1]-1≤t_n相似文献   

Ⅲa＝0（－1＜n＜0，0＜l＜1）类二次系统存在极限环的充要条件

本文利用旋转向量场理论得到了系统ｘ＝－ｙ＋δｘ＋ｌｘ２＋ｍｘｙ＋ｎｙ２，ｙ＝ｘ（１＋ｙ），｛（－１＜ｎ＜０，０＜ｌ＜１）存在极限环的充要条件．     

ON INTERPOLATION BY S_3~1(△_mn~(1))(I)

§0 Introduction Let △_(mn)~(1) be a subdivision of D: [a,b]x[c,d] (Fig.1). l_1,_2be lengths of [a,b] and [c,d] respectively, and h_1=l_1/m, h_2=l_2/n,l=max(l_1,l_2). Suppose that S∈S1/3(△_(mn)~(1)). In §1-§5 we consider thefollowing interpolation problem:     

APPROXIMATION PROPERTIES OF LAGRANGE INTERPOLATION POLYNOMIAL BASED ON THE ZEROS OF （1- x^2）cosnarccosx

We study some approximation properties of Lagrange interpolation polynomial based on the zeros of （1-x^2）cosnarccosx. By using a decomposition for f（x） ∈ C^τC^τ＋1 we obtain an estimate of ‖f（x） -Ln＋2（f, x）‖ which reflects the influence of the position of the x＇s and ω（f^（r＋1）,δ）j,j = 0, 1,... , s,on the error of approximation.     

ON STABILITY OF m-VARIATE C~1 INTERPOLATION

A.simplicial mesh(triangulation)is constructed that generalizes the two-dimensional 4-directionmesh to R~m.This mesh,with symmetric,shift-invariant values at the vertices,is shown to admit a boundedC~1 interpolant if and only if the alternating sum of the values at the vertices of any 1-cube is zero.This im-plies thai interpolation at the vertices of an m-dimensional,simplicial mesh by a C~1 piecewise polynomial ofdegree m+1 with one piece per simplex is unstable.