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Exponential fitting of restricted rational approximations to the exponential function

  • Syvert P. Norsett
  • Stewart R. Trickett
Numerical Methods
Part of the Lecture Notes in Mathematics book series (LNM, volume 1105)

Abstract

Let Rn/m(z, γ)=Pn(z; γ)/(1-γz)m be a restricted rational approximation to exp(z), zεℂ, of order n for all real γ. In this paper we discuss how γ can be used to obtain fitting at a real non-positive point z1. It is shown that there are exactly min(n+1, m) different positive values of γ with this property.

Keywords

Rational Approximation Laguerre Polynomial Exponential Fitting Real Polis Pade Approximation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • Syvert P. Norsett
    • 1
  • Stewart R. Trickett
    • 2
  1. 1.Department of Computer ScienceUniversity of WaterlooWaterlooCanada
  2. 2.Department of Applied MathematicsUniversity of WaterlooWaterlooCanada

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