FW: Numerical Hypergeometric Functions

["Daniel Lozier" <lozier@nist.gov>]

Editor's Note:  A recently updated report by Frank Olver and me,
"Numerical Evaluation of Special Functions," contains an extensive
listing of available software.  It is available on the Web at
http://math-i.nist.gov/mcsd/Reports/2001/nesf/.

Dan Lozier

Sender: David Strozzi <dstrozzi@MIT.EDU>
Subject: Numerical Hypergeometric Functions


I am looking for a way to numerically compute the hypergeometric
function (the famous 2F1).  I need it for complex parameters (namely the
a and b in F(a,b;c;z) Abramowitz and Stegun notation) and analytically
continued outside the unit disk (along the negative real axis).

Any ideas?  Is there code for this on the web?  Is there a good article
or book that can be followed in a somewhat cookbook manner?

The function I need happens to be of the form F(a , b; a+b; -real^2),
and this can be "simplified" (A+S 15.3.10) to an infinite sum of Psi
functions.

Thanks a lot.

--
David Strozzi                             dstrozzi@mit.edu
home: 472 Putnam Ave., Apt. 2B     office: Bldg. NW 16-223
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