Computation of parabolic cylinder functions having complex argument

Numerical methods for the computation of the parabolic cylinder function U(a,z) for real a and complex z are presented. The main tools are recent asymptotic expansions involving exponential and Airy functions, with slowly varying analytic coefficient functions involving simple coefficients, and stab...

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Detalles Bibliográficos
Autores: Dunster, T.M., Gil Gómez, Amparo|||0000-0002-7449-4205, Segura Sala, José Javier|||0000-0002-0841-5636
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/31000
Acceso en línea:https://hdl.handle.net/10902/31000
Access Level:acceso abierto
Palabra clave:Parabolic cylinder functions
Asymptotic expansions
Numerical quadrature
Numerical algorithms
Descripción
Sumario:Numerical methods for the computation of the parabolic cylinder function U(a,z) for real a and complex z are presented. The main tools are recent asymptotic expansions involving exponential and Airy functions, with slowly varying analytic coefficient functions involving simple coefficients, and stable integral representations; these two main methods can be complemented with Maclaurin series and a Poincaré asymptotic expansion. We provide numerical evidence showing that the combination of these methods is enough for computing the function with 5 × 10-13 relative accuracy in double precision floating point arithmetic.