This paper analysis the local behavior of the bivariate quadratic function approximation to a bivariate function which has a given power series expansion about the origin. It is shown that the bivariate quadratic Hermite-Padé form always defines a bivariate quadratic function and that this function is analytic in a neighborhood of the origin.
In this paper,we propose a method to deal with numerical integral by using two kinds of C^2 quasi-interpolation operators on the bivariate spline space,and also dis- cuss the convergence properties and error estimates.Moreover,the proposed method is applied to the numerical evaluation of 2-D singular integrals.Numerical exper- iments will be carried out and the results will be compared with some previously published results.
The polynomials related with cubic Hermite-Padé approximation to the exponential function are investigated which have degrees at most n, m, s respectively. A connection is given between the coefficients of each of the polynomials and certain hypergeometric functions, which leads to a simple expression for a polynomial in a special case. Contour integral representations of the polynomials are given. By using of the saddle point method the exact asymptotics of the polynomials are derived as n, m, s tend to infinity through certain ray sequence. Some further uniform asymptotic aspects of the polynomials are also discussed.
Semialgebraic sets are objects which are truly a special feature of real algebraic geometry. This paper presents the piecewise semialgebraic set, which is the subset of Rn satisfying a boolean combination of multivariate spline equations and inequalities with real coefficients. Moreover, the stability under projection and the dimension of C^μ piecewise semialgebraic sets are also discussed.
In this paper, we propose a new approach to solve the approximate implicitization problem based on RBF networks and MQ quasi-interpolation. This approach possesses the advantages of shape preserving, better smoothness, good approximation behavior and relatively less data etc. Several numerical examples are provided to demonstrate the effectiveness and flexibility of the proposed method.
In this note, we investigate the necessity for the measure dψ being a strong distribution, which is associated with the coefficients of the recurrence relation satisfied by the orthogonal Laurent polynomials. We also give out a representation of the greatest zeros of orthogonal Laurent polynomials in the case of dψ being a strong distribution.
