In this work we present a numerical scheme to compute the two-variable hypergeometric function F1(α, β, β′, γ; x, y) of Appell for complex parameters α, β, β′ and γ, and real values of the variables x and y. We implement a set of analytic continuations that allow us to obtain the F1 function outside the region of convergence of the series definition. These continuations can be written in terms of the Horn's G2 function, Appell's F2 function related, and the F1 hypergeometric itself. The computation of the function inside the region of convergence is achieved by two complementary methods. The first one involves a single-index series expansion of the F1 function, while the second one makes use of a numerical integration of a third order ordinary differential equation that represents the system of partial differential equations of the F1 function. We briefly sketch the program and show some examples of the numerical computation. © 2001 Elsevier Science B.V.
Documento: | Artículo |
Título: | Numerical evaluation of Appell's F1 hypergeometric function |
Autor: | Colavecchia, F.D.; Gasaneo, G.; Miraglia, J.E. |
Filiación: | Centro Atómico Bariloche, Consejo Nacional De Investigaciones Científicas Y Técnicas, 8400 S.C. de Bariloche, Argentina Departmento De Física, Universidad Nacional del Sur, Av. Alem 1453, 8000 Bahía Blanca, Argentina Instituto De Física Y Astronomía del Espacio, Consejo Nacional De Investigaciones Científicas Y Técnicas, 1428 Buenos Aires, Argentina Theoretical Division (T-12, MS B268), Los Alamos National Laboratory, Los Alamos, NM 87545, United States |
Palabras clave: | Appell functions; Gauss function; Hypergeometric functions; Numerical methods; Special functions; Computational complexity; Computational geometry; Convergence of numerical methods; Integration; Ordinary differential equations; Partial differential equations; Appell's function; Horn's function; Hypergeometric functions; Function evaluation |
Año: | 2001 |
Volumen: | 138 |
Número: | 1 |
Página de inicio: | 29 |
Página de fin: | 43 |
DOI: | http://dx.doi.org/10.1016/S0010-4655(01)00186-2 |
Título revista: | Computer Physics Communications |
Título revista abreviado: | Comput Phys Commun |
ISSN: | 00104655 |
CODEN: | CPHCB |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00104655_v138_n1_p29_Colavecchia |