Abstract
Numerous versions of the Lanczos τ-methods have been extensively used to produce polynomial approximations for functions verifying a linear differential equation with polynomial coefficients. In the case of an initial-value problem, an adapted τ-method based on Chebyshev series and the use of symbolic computation lead to a rational approximation of the solution on a region of the complex plane. Numerical examples show that the simplicity of the method does not prevent a high accuracy of results.
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References
M. Abramowitz and I.A. Stegun, eds., Handbook ofMathematical Functions with Formulas, Graphs and Mathematical Tables, Applied Math. Series, Vol. 5 (National Bureau of Standards, Washington, DC, 9th ed., 1964).
E. Borel, Leçon sur les SériesDivergentes (Gauthier-Villars, Paris, 1928).
C. Clenshaw, Numericalsolution of linear differential equations in Chebyshev series, Proc. Cambridge Phi. Soc. 53 (1957) 134–149.
J.P. Coleman, Complex polynomialapproximation by the Lanczos τ-method: Dawson's integral, J. Comput. Appl. Math. 20 (1987) 137–151.
J.P. Coleman, Polynomialapproximations in the complex plane, J. Comput. Appl. Math. 18 (1987) 193–211.
L. Fox and I.B. Parker, Chebyshev Polynomials inNumerical Analysis (Oxford University Press, London, 1968).
K. Geddes, Symbolic computation of recurrence equations for the Chebyshev series solution of linear ODEs, in: MACSYMA Users Conf. (1997) pp. 405–423.
J.F. Hart et al., Computer Approximations (Wiley, New York,1968).
E.L. Ince, Ordinary Differential Equations (Dover, NewYork, 1956).
C. Lanczos, Applied Analysis (Prentice-Hall, London, 1956).
G.O. Olaefe, On Tchebyschev method of solution ofordinary differential equations, J. Math. Anal. Appl. 60 (1977) 1–7.
L. Rebillard, Séries de Chebyshev formelles, Rapport deRecherche RR 960, Laboratoire de Modélisation et de Calcul, LMC-IMAG, Grenoble, France (September 1996).
T. Rivlin, ChebyshevPolynomials (Wiley, New York, 1974).
G. Szegö,Orthogonal Polynomials (Amer. Math. Soc., New York, 1959).
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Rebillard, L. Rational approximation in the complex plane using a τ-method and computer algebra. Numerical Algorithms 16, 187–208 (1997). https://doi.org/10.1023/A:1019143231331
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DOI: https://doi.org/10.1023/A:1019143231331