Highly Efficient and Accurate Spectral Approximation of the Angular Mathieu Equation for any Parameter Values <i>q</i>


Alici H., Shen J.

JOURNAL OF MATHEMATICAL STUDY, cilt.51, sa.2, ss.131-149, 2018 (ESCI) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 51 Sayı: 2
  • Basım Tarihi: 2018
  • Doi Numarası: 10.4208/jms.v51n2.18.02
  • Dergi Adı: JOURNAL OF MATHEMATICAL STUDY
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI)
  • Sayfa Sayıları: ss.131-149
  • Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

The eigenpairs of the angular Mathieu equation under the periodicity condition are accurately approximated by the Jacobi polynomials in a spectral-Galerkin scheme for small and moderate values of the parameter q. On the other hand, the periodic Mathieu functions are related with the spheroidal functions of order +/- 1/2. It is well-known that for very large values of the bandwidth parameter, spheroidal functions can be accurately approximated by the Hermite or Laguerre functions scaled by the square root of the bandwidth parameter. This led us to employ the Laguerre polynomials in a pseudospectral manner to approximate the periodic Mathieu functions and the corresponding characteristic values for very large values of q.