Étude et convergence de fonctions «spline» complexes
Evaluation de l'erreur dans la méthode des éléments finis.
Extending n-convex functions
We are given data α₁,..., αₘ and a set of points E = x₁,...,xₘ. We address the question of conditions ensuring the existence of a function f satisfying the interpolation conditions , i = 1,...,m, that is also n-convex on a set properly containing E. We consider both one-point extensions of E, and extensions to all of ℝ. We also determine bounds on the n-convex functions satisfying the above interpolation conditions.
Extension via interpolation
We suggest a modification of the Pawłucki and Pleśniak method to construct a continuous linear extension operator by means of interpolation polynomials. As an illustration we present explicitly the extension operator for the space of Whitney functions given on the Cantor ternary set.
Extensions and Selections in Subspaces of C(K).
Fonctions d'échelle interpolantes, polynômes de Bernstein et ondelettes non stationnaires.
The theory of convergence for (non-stationary) scaling functions and the approximation of interpolating scaling filters by means of Bernstein polynomials, allow us to construct a non-stationary interpolating scaling function with interesting approximation properties.
Fonctions spline par moyennes locales sur un ouvert borné de
Formation of Singularities in Fluid Interfaces
General Order Newton-Padé Approximants for Multivariate Functions.
Generalized Birkhoff interpolation schemes: conditions for almost regularity.
Generalized Pólya condition for Birkhoff interpolation with lacunary polynomials.
Global smoothness preservation by some nonlinear max-product operators
Harmonic interpolating sequences, and BMO
Let be a sequence in the upper half plane. If and ifhas solution in the class of Poisson integrals of functions for any sequence , then we show that is an interpolating sequence for . If , has solution in the class of Poisson integrals of BMO functions whenever , then is again an interpolating sequence for . A somewhat more general theorem is also proved and a counterexample for the case is described.
Harmonic interpolation based on Radon projections along the sides of regular polygons
Given information about a harmonic function in two variables, consisting of a finite number of values of its Radon projections, i.e., integrals along some chords of the unit circle, we study the problem of interpolating these data by a harmonic polynomial. With the help of symbolic summation techniques we show that this interpolation problem has a unique solution in the case when the chords form a regular polygon. Numerical experiments for this and more general cases are presented.
Hermite interpolation: a survey of univariate computational methods.
Se considera la interpolación de Hermite de funciones de una variable mediante polinomios generalizados. Se pretende mostrar que técnicas computacionales conocidas para interpolación polinómica se pueden aplicar también a interpolación mediante polinomios generalizados. Como aplicación se estudia con cierto detalle la interpolación mediante funciones racionales con polos prefijados. La interpolación polinómica corresponde al caso particular en que todos los polos prefijados están en el infinito.
Hermite interpolation and an inequality for entire functions of exponential type.
Hyperbolic splines with given derivatives at the knots
Ideal interpolation: Mourrain's condition vs. D-invariance
Mourrain [Mo] characterizes those linear projectors on a finite-dimensional polynomial space that can be extended to an ideal projector, i.e., a projector on polynomials whose kernel is an ideal. This is important in the construction of normal form algorithms for a polynomial ideal. Mourrain's characterization requires the polynomial space to be 'connected to 1', a condition that is implied by D-invariance in case the polynomial space is spanned by monomials. We give examples to show that, for more...
Independence with respect to families of characters
Inequalities for Fourier transforms