Hypergeometric 2F1() specfunc: cases x=1

[Brian Gough]

At Tue, 11 Dec 2007 22:14:27 +0100,
Richard Mathar wrote:
> It would be nice if the implementation of the Gaussian hypergeometric
> functions would catch the special case of unit argument and compute it
> via the standard formula with the Gamma functions (Abramowitz & Stegun 15.1.20).

Sounds reasonable --- can you write some test cases with high
precision values for specfunc/test_hyperg.c to make sure it's working.

-- 
Brian Gough