A powerful and versatile method of shape-preserving interpolation is developed in terms of piecewise exponential functions with a tension factor associated with each interval. Knots coincide with data points, and the interpolant is formulated in terms of its values and first derivatives at these points. For a given set of derivatives, this enables the efficient computation of the minimum tensio...

Abstract Given gridded cell-average data of a smooth multivariate function, we present constructive explicit procedure for generating high-order global approximation the function. One contribution is derivation approximations to point-values function directly from data. The second development univariate B-spline-based quasi-interpolation operators using Multivariate spline are obtained by tenso...

Under mild additional assumptions this paper constructs quasi -interpolants in the form f h (x) = +1 X j= 1 f(hj)' h x h j ; x 2 IR; h > 0 (0.1) with approximation order ` 1, where ' h (x) is a linear combination of translates (x jh) of a function in C ` (IR). Thus the order of convergence of such operators can be pushed up to a limit that only depends on the smoothness of the function . This a...

We consider laminar mixing in a steady incompressible Newtonian uid. Through the use of particle tracking methods and analogous techniques applicable to material element vectors on a given velocity eld, residence time distributions, Poincare maps and material element deformations are computed; all of which are useful tools in determining the eecacy of a mixing system. We analyse the accuracy of...

orthogonal zero interpolants (ozi) are polynomials which interpolate the “zero-function” at a finite number of pre-assigned nodes and satisfy orthogonality condition. ozi’s can be constructed by the 3-term recurrence relation. these interpolants are found useful in the solution of constrained approximation problems and in the structure of gauss-type quadrature rules. we present some theoretical...

A quasi-interpolation method for quadratic piecewise polynomials in three variables is described which can be used for the efficient visualization of gridded volume data. We analyze the smoothness properties of the trivariate splines. We prove that the splines yield nearly optimal approximation order while simultaneously its piecewise derivatives provide optimal approximation of the derivatives...

in this article, a numerical approximation to the solution of the newell-whitehead equation (nwe) and cauchy problem of ill-posed non-linear diffusion equation have been studied. the presented scheme is obtained by using the derivative of the cubic b-spline quasi-interpolation (bsqi) to approximate the spatial derivative of the dependent variable and first order forward difference to approximat...