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Reliable operations on oscillatory functions

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 نشر من قبل Gheorghe Adam
 تاريخ النشر 1999
  مجال البحث
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Approximate $p$-point Leibniz derivation formulas as well as interpolatory Simpson quadrature sums adapted to oscillatory functions are discussed. Both theoretical considerations and numerical evidence concerning the dependence of the discretization errors on the frequency parameter of the oscillatory functions show that the accuracy gain of the present formulas over those based on the exponential fitting approach [L. Ixaru, Computer Physics Communications, 105 (1997) 1--19] is overwhelming.

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