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Computation of highly oscillatory Bessel transforms with algebraic singularities

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 نشر من قبل Zhenhua Xu
 تاريخ النشر 2016
  مجال البحث
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In this paper, we consider the Clenshaw-Curtis-Filon method for the highly oscillatory Bessel transform $int_0^1x^alpha (1-x)^beta f(x) J_{ u}(omega x)dx$, where $f$ is a smooth function on $[0, 1]$, and $ ugeq0.$ The method is based on Fast Fourier Transform (FFT) and fast computation of the modified moments. We give a recurrence relation for the modified moments and present an efficient method for the evaluation of modified moments by using recurrence relation. Moreover, the corresponding error bound in inverse powers of $N$ for this method for the integral is presented. Numerical examples are provided to support our analysis and show the efficiency and accuracy of the method.



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