Local Lagrange Interpolation with Bivariate Splines of Arbitrary Smoothness

Abstract We describe a method which can be used to interpolate function values at a set of scattered points in a planar domain using bivariate polynomial splines of any prescribed smoothness. The method starts with an arbitrary given triangulation of the data points, and involves refining some of the triangles with Clough-Tocher splits. The construction of the interpolating splines requires some additional function values at selected points in the domain, but no derivatives are needed at any point. Given n data points and a corresponding initial triangulation, the interpolating spline can be computed in just O(n) operations. The interpolation method is local and stable, and provides optimal order approximation of smooth functions.

[1]  D. Wilhelmsen,et al.  A Markov inequality in several dimensions , 1974 .

[2]  Frank Zeilfelder,et al.  Lagrange Interpolation by C1 Cubic Splines on Triangulated Quadrangulations , 2004, Adv. Comput. Math..

[3]  A. Ženíšek,et al.  A general theorem on triangular finite $C^{(m)}$-elements , 1974 .

[4]  L. R. Scott,et al.  The Mathematical Theory of Finite Element Methods , 1994 .

[5]  G. Nürnberger,et al.  Fundamental Splines on Triangulations , 2003 .

[6]  Frank Zeilfelder,et al.  Local Lagrange Interpolation by Cubic Splines on a Class of Triangulations , 2001 .

[7]  Frank Zeilfelder,et al.  Lagrange Interpolation by C1 Cubic Splines on Triangulations of Separable Quadrangulations , 2002 .

[8]  Frank Zeilfelder,et al.  Local Lagrange interpolation by bivariate C 1 cubic splines , 2001 .

[9]  Schumaker,et al.  Upper and Lower Bounds on the Dimension of Superspline Spaces , 2003 .

[10]  Frank Zeilfelder,et al.  Bivariate spline interpolation with optimal approximation order , 2001 .

[11]  Frank Zeilfelder,et al.  Scattered Data Fitting by Direct Extension of Local Polynomials to Bivariate Splines , 2004, Adv. Comput. Math..

[12]  Larry L. Schumaker,et al.  On the approximation power of bivariate splines , 1998, Adv. Comput. Math..

[13]  Frank Zeilfelder,et al.  Local Lagrange Interpolation on Powell-Sabin Triangulations and Terrain Modelling , 2001 .

[14]  P. Sablonnière,et al.  Triangular finite elements of HCT type and classCρ , 1994, Adv. Comput. Math..

[15]  Charles K. Chui,et al.  Construction of local C1 quartic spline elements for optimal-order approximation , 1996, Math. Comput..

[16]  Frank Zeilfelder,et al.  Lagrange Interpolation by Bivariate C1-Splines with Optimal Approximation Order , 2004, Adv. Comput. Math..

[17]  L. Schumaker,et al.  Scattered Data Interpolation Using C 2 Supersplines of Degree Six , 1997 .

[18]  Larry L. Schumaker,et al.  Smooth macro-elements based on Clough-Tocher triangle splits , 2002, Numerische Mathematik.

[19]  Frank Zeilfelder,et al.  Developments in bivariate spline interpolation , 2000 .

[20]  A. Ženíšek Interpolation polynomials on the triangle , 1970 .

[21]  Tracy Whelan,et al.  A representation of a C2 interpolant over triangles , 1986, Comput. Aided Geom. Des..

[22]  Don Hong,et al.  Stability of optimal-order approximation by bivariate splines over arbitrary triangulations , 1995 .

[23]  Larry L. Schumaker,et al.  C1 Quintic Splines on Type-4 Tetrahedral Partitions , 2004, Adv. Comput. Math..

[24]  Gerald E. Farin,et al.  A modified Clough-Tocher interpolant , 1985, Comput. Aided Geom. Des..