Padé-Gegenbauer suppression of Runge phenomenon in the diagonal limit of Gegenbauer approximations

نویسنده

  • Laura B. Lurati
چکیده

Boyd shows in [3] that for a function with singularities in the imaginary plane, the Gegenbauer expansion of the function may have Runge-type oscillations so large that all hope of convergence for the method is lost. We consider the use of Padé-Gegenbauer interpolants to resolve these oscillations. We describe a fast interpolation-based reconstruction for computing the Padé-Gegenbauer approximants and demonstrate its excellent performance on test examples. This method resolves the oscillations and restores accuracy to the Gegenbauer approximation of a function with singularities in the imaginary plane without measuring the proximity of these off-axis singularities.

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عنوان ژورنال:
  • J. Comput. Physics

دوره 222  شماره 

صفحات  -

تاریخ انتشار 2007