Abstract
This paper concerns two fundamental interpolants to convex bivariate scattered data. The first,u, is the supremum over all convex Lagrange interpolants and is piecewise linear on a triangulation. The other,l, is the infimum over all convex Hermite interpolants and is piecewise linear on a tessellation. We discuss the existence, uniqueness, and numerical computation ofu andl and the associated triangulation and tessellation. We also describe how to generate convex Hermite data from convex Lagrange data.
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L. E. Andersson, T. Elfving, G. Iliev and K. Vlachkova, Interpolation of convex scattered data in ℝ3 based upon an edge convex minimum norm network, J. Approx. Theory 80 (1995) 299–320.
J. M. Carnicer, Multivariate convexity preserving interpolation by smooth functions, Adv. Comput. Math. 3 (1995) 395–404.
J. M. Carnicer and W. Dahmen, Convexity preserving interpolation and Powell-Sabin elements, Comput. Aided Geom. Design 9 (1992) 279–289.
W. Dahmen and C. A. Micchelli, Convexity of multivariate Bernstein polynomials and box spline surfaces, Studia Sci. Math. Hungar. 23 (1988) 265–287.
H. Edelsbrunner and R. Seidel, Voronoi diagrams and arrangements, Discrete Comput. Geom. 1 (1986) 25–44.
C. L. Lawson, Generation of a triangular grid with application to contour plotting, Jet Propulsion Laboratory, Internal Technical Memorandum No. 299, Pasadena, CA (1972).
B. Mulansky, Interpolation of scattered data by a bivariate convex function I: Piecewise linearC 0-interpolation, Memorandum No. 858, University of Twente (1990).
F. P. Preparata and M. I. Shamos,Computational Geometry (Springer, New York, 1985).
R. T. Rockafellar,Convex Analysis (Princeton University Press, Princeton, 1970).
L. L. Schumaker, Triangulation methods, in:Topics in Multivariate Approximation, eds. C. K. Chui, L. L. Schumaker and F. Utreras (Academic Press, New York, 1987) pp. 219–232.
D. S. Scott, The complexity of interpolating given data in three-space with a convex function in two variables, J. Approx. Theory 42 (1984) 52–63.
R. Sibson, Locally equiangular triangulations, Computer J. 21 (1978) 243–245.
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Communicated by M. Gasca
Research partially supported by the EU Project FAIRSHAPE, CHRX-CT94-0522. The first author was also partially supported by DGICYT PB93-0310 Research Grant.
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Carnicer, J.M., Floater, M.S. Piecewise linear interpolants to Lagrange and Hermite convex scattered data. Numer Algor 13, 345–364 (1996). https://doi.org/10.1007/BF02207700
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DOI: https://doi.org/10.1007/BF02207700