An adaptive contour code for the numerical evaluation of the oscillatory cuspoid canonical integrals and their derivatives

Abstract
We present a code to compute the oscillatory cuspoid canonical integrals and their first order partial derivatives. The algorithm is based on the method of Connor and Curtis [J. Phys. A 15 (1982) 1179–1190], in which the integration path along the real axis is replaced by a more convenient contour in the complex plane, rendering the oscillatory integrand more amenable to numerical quadrature. Our code is a modern implementation of this method, presented in a modular fashion as a Fortran 90 mo...

Title of program: cuspint
Catalogue Id: ADMP_v1_0

Nature of problem
The theoretical treatment of short wavelength scattering phenomena often involves the uniform asymptotic evaluation of oscillating integrals with several coalescing saddle points. An important practical problem then is the numerical evaluation of the cuspoid canonical integrals and their first order partial derivatives.

Versions of this program held in the CPC repository in Mendeley Data
ADMP_v1_0; cuspint; 10.1016/S0010-4655(00)00126-0

This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)