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Outline

Generalized Bernstein polynomials and total positivity

1999

Abstract

This thesis submitted for Ph.D. degree deals mainly with geometric properties of generalized Bernstein polynomials which replace the single Bernstein polynomial Bn! by a one-parameter family of polynomials B~!. It also provides a triangular decomposition and l-banded factorization of the Vandermonde matrix. We first establish the generalized Bernstein polynomials for monomials, which leads to a definition of Stirling polynomials of the second kind. These are q-analogues of Stirling numbers of the second kind. Some of the properties of the Stirling numbers are generalized to their q-analogues. We show that the generalized Bernstein polynomials are monotonic in degree n, that is B~! ~ B~+d, when the function! is convex. There is also a representation of B~! B~+1!involving second order divided differences of the function j'. Shape preserving properties of the generalized Bernstein polynomials are studied by making use of the concept of total positivity. It is proved that monotonic ...

References (54)

  1. G. E. ANDREWS, The Theory of Partitions, Cambridge University Press, 1998, chapter 3.
  2. H. BOHMAN, On approximation of continuous and of analytic functions, Arkiv for Matematik, 2 (1952), pp. 43-56.
  3. L. CARLITZ, q-Bernoulli numbers and polynomials, Duke Mathematical Journal, 15 (1948), pp. 987-1000.
  4. J. M. CARNICER AND J. PENA, Totally positive bases for shape preserving curve design and optimality of B-splines, Computer Aided Geometric Design, 11 (1994), pp. 633-654.
  5. J. M. CARNICER AND J. M. PENA, Shape preserving representations and optimality of the Bernstein basis, Advances in Computational Mathematics, 1 (1993), pp.173-196.
  6. E. W. CHENEY, Introduction to Approximation Theory, Chelsea, second ed., 1984, chapter 2.
  7. C. W. CRYER, Some properties of totally positive matrices, Linear Algebra and its Applications, 15 (1976), pp. 1-25.
  8. W. DAHMEN, Convexity and Bernstein-Bezier polynomials, in Curves and Surfaces, P. J. Laurent, A. L. Mehaute, and L. L. Schumaker, eds., 1991, pp. 107-134.
  9. P. J. DAVIS, Interpolation and Approximation, Dover, 1975, chapter 6.
  10. C. DE BOOR AND A. PINKUS, Backward error analysis for totally positive systems, Numerische Mathematik, 27 (1977), pp. 485-490.
  11. P. DE CASTELJAU, Shape Mathematics and CAD, Kogan Page Ltd., 1986.
  12. R. A. DEVORE AND G. G. LORENTZ, Constructive Approximation, Springer-Verlag, 1993, chapter 10.
  13. H. EXTON, q-Hypergeometric Functions and Applications, Ellis Horwood, 1983, chapter 2.
  14. G. FARIN, Curves and Surfaces for Computer Aided Geometric Design, A Practical Guide, Academic Press, fourth ed., 1997, chapter 3-5.
  15. R. T. FAROUKI AND T. N. T. GOODMAN, On the optimal stability of the Bernstein basis, Mathematics of Computation, 65 (1996), pp. 1553-1566.
  16. R. T. FAROUKI AND V. T. RAJAN, On the numerical condition of poly- nomials in Bernstein form, Computer Aided Geometric Design, 4 (1987), pp. 191-216.
  17. T. N. T. GOODMAN, Shape preserving representations, in Mathematical Methods in CAGD, T. Lyche and L. Schumaker, eds., Academic Press, Boston, MA, 1989, pp. 333-357.
  18. --, Total positivity and shape of curves, in Total Positivity and its Appli- cations, M. Gasca and C. A. Micchelli, eds., 1996, pp. 157-186.
  19. T. N. T. GOODMAN, H. ORUQ, AND G. M. PHILLIPS, Convexity and gen- eralized Bernstein polynomials, Proceedings of the Edinburgh Mathematical Society, in the press.
  20. T. N. T. GOODMAN AND H. B. SAID, Properties of generalized Ball curves and surfaces, Computer Aided Design, 23 (1991), pp. 554-560.
  21. --, Shape preserving properties of the generalized Ball basis, Computer Aided Geometric Design, 8 (1991), pp. 115-121.
  22. T. N. T. GOODMAN AND A. SHARMA, Factorization of totally positive, symmetric, periodic, banded matrices with applications, Linear Algebra and its Applications, 178 (1993), pp. 85-107.
  23. H. W. GOULD, q-Stirling numbers of first and second kinds, Duke Mathe- matical Journal, 28 (1961), pp. 281-289.
  24. J. HOSCHEK AND D. LASSER, Fundamentals of Computer Aided Geometric Design, A K Peters, 1993, chapter 4.
  25. F. H. JACKSON, On q-functions and a certain difference operator, Transac- tions of the Royal Society of Edinburgh, 46 (1908), pp. 253-281.
  26. --, On q-definite integrals, Quarterly Journal of Pure and Applied Math- ematics, 41 (1910), pp. 193-203.
  27. --, Basic integration, Quarterly Journal of Mathematics, Oxford Series, 2 (1951), pp. 1-16.
  28. S. KARLIN, Total Positivity, Stanford University Press, 1967, chapter 6.
  29. Z. F. KOQAK AND G. M. PHILLIPS, An identity involving the q-factorial, in Applications of Fibonacci numbers, Kluwer, 1996.
  30. J. KONVALIN, Generalized-Binomial Coefficients and the Subset-Subspace
  31. Problem, Advances in Applied Mathematics, 21 (1998), pp. 228-240.
  32. P. P. KOROVKIN, On convergence oj linear positive operators in the space oj continuous Junctions, Doklady Akademii Nauk SSSR, 114 (1957), pp. 961- 964.
  33. L. KOSMAK, A note on Bernstein polynomials oj a convex Junction, Math- ematica (Cluj), 2 (1960), pp. 281-282.
  34. S. L. LEE AND G. M. PHILLIPS, Polynomial interpolation at the points oj a geometric progression, Proceedings of the Royal Society Edinburgh, 108A (1988), pp. 75-87.
  35. G. G. LORENTZ, Bernstein polynomials, University of Toronto Press, 1953, chapter 1-2.
  36. I. G. MACDONALD, Symmetric Functions and Hall polynomials, Clarendon Press Oxford, 1979, chapter 1.
  37. A. D. MEDICS AND P. LEROUX, Generalized Stirling numbers, convolution Jormula and p, q-analogues, Canadian Journal Mathematics, 47(3) (1995), pp.474-499.
  38. L. M. MILNE-THOMSON, Calculus oj Finite Differences, Macmillan, 1951, chapter 1.
  39. E. NEUMAN, On complete symmetric Junctions, SIAM Journal on Mathe- matical Analysis, 19 (1988), pp. 736-750.
  40. H. ORUg AND G. M. PHILLIPS, A generalization oj Bernstein polynomials, Proceedings of the Edinburgh Mathematical Society, in the press.
  41. G. M. PHILLIPS, A de Casteljau algorithm Jor generalized Bernstein poly- nomials, BIT, 36:1 (1996), pp. 232-236.
  42. --, On generalized Bernstein polynomials, in Numerical Analysis: A.R. Mitchell 75th Birthday Volume, D. Griffiths and G. Watson, eds., 1996, pp. 263-269.
  43. --, Bernstein polynomials based on q-integers, Annals of Numerical Math- ematics,4 (1997), pp. 511-518.
  44. G. M. PHILLIPS AND P. J. TAYLOR, Theory and Applications of Numerical Analysis, Academic Press, second ed., 1996, chapter 5.
  45. G. POLYA AND I. J. SCHOENBERG, Remarks on the de la Vallee Poussin means and convex conformal maps of the circle, Pacific Journal of Mathe- matics, 8 (1958), pp. 295-334.
  46. L. RAMSHAW, Blossoms are polar forms, Computer Aided Geometric De- sign, 6 (1989), pp. 323-358.
  47. T. J. RIVLIN, An Introduction to the Approximation of functions, Dover, 1969, chapter 1.
  48. I. J. SCHOENBERG, On smoothing operations and their generating functions, Bulletin of the American Mathematical Society, 59 (1953), pp. 199-230.
  49. --, On variation diminishing approximation methods, in On Numerical Approximation Methods, R. E. Langer, ed., 1959, pp. 249-271.
  50. --, On polynomial interpolation at the points of a geometric progression, Proceedings of the Royal Society Edinburgh, 90A (1981), pp. 195-207.
  51. I. TOMESCU, Introduction to Combinatorics, London and Wellingborough: Collet's, 1975, chapter 2.
  52. T.POPOVICIU, Sur l'approximation desfonctions convexes d'ordre superieur, Mathematica, 10 (1935), pp. 49-54.
  53. E. VORONOVSKAYA, Determination de la Jorme asymptotique d 'approximation des Junctions par les polynomes de M. Bernstein, Doklady Akademii Nauk SSSR, 4 (1932), pp. 79-85.
  54. R. WEBSTER, Convexity, Oxford Science Publication, 1994, chapter 5.