🚀 go-pugleaf

   I often have to perform numerical integrals of the form


          /\ infinity
         / 
        /      f(x) dx
       /
     \/ 0

where f(x) is oscillating and the integral of |f(x)| diverges
[f(x) often behaves like sin(omega*x+phi)/sqrt(x) for large x].
Are there any really accurate numerical integration methods for
this class of problems (I need at least 7 digit precision),
apart from rotating the integration contour in the complex plane
to imaginary x?  (contour integration works very well, but takes
a lot of analytical effort: I have identify all poles and cuts
of f, which is a very complicated transcendent function,
depending on parameters...)

   Thanks in advance,

-- 
        Massimo Campostrini, 
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa,
Piazza Torricelli 2, I-56126 Pisa, Italy  ||  Phone: (+39)(50)42093
Internet: campo@sunthpi3.difi.unipi.it    ||  Fax:   (+39)(50)48277