README  special functions

    erf.c       : the error function
    ibeta.c     : the incomplete beta function
    igamma.c    : the incomplete gamma function
    inv_erf.c   : the inverse of the error function
    s_erf.c     : the error function (from glib.c)


SIAM Activity Group on Orthogonal Polynomials and Special Functions
 at: http://www.math.yorku.ca/Who/Faculty/Muldoon/siamopsf/

http://www.letlib.org/
Look in NETLIB under random for dcdflib.c.  This has CDF's and inverse CDF's
for many functions.  The file is called a tar, but it is really a gz.  So
you must rename it before you can open it.  Well documented and complies
easily under gcc or VC.
Example Netlib Search at URL http://www.netlib.org/utk/misc/netlib_query.html
and in the search box enter "complementary incomplete gamma" 
(including the quotation marks).

http://lib.stat.cmu.edu/
Just get AS 66 for the normal distribution function, and AS 241 for its
inverse.  The Applied Statistics algorithms were published by the
Royal Statistical Society.  They can be downloaded from statlib
(http://lib.stat.cmu.edu).  They are both in Fortran, though some of the
RSS algorithms were in Algol and Pascal, and one was in C.

Erf:
http://www.netlib.org/specfun/erf.

Phi, InvPhi:
Alan Miller, Retired Scientist (Statistician)
CSIRO Mathematical & Information Sciences
Alan.Miller -at- vic.cmis.csiro.au
http://www.ozemail.com.au/~milleraj

InvPhi:
http://www.math.uio.no/~jacklam/notes/invnorm/

Gamma:
Stephen L. Moshier wins the prize.  He has the gamma function written at
hardware precisions from float to double to 80 bit long double and 128 bit
long double as well as an extended precision version called qfloat.  It's at
Netlib, in the Cephes collection.  Have fun.

* Factorial(z) = Gamma(z+1)
*
*         - y(z) - z - 1               z + 1              2            7
*       %e               (y(z) + z + 1)      sqrt(%pi (2 y (z) + 2 z + -))
*                                                                      3
*  z! ~ ------------------------------------------------------------------,
*                                     z + 1
*
*         0.5396181799525381 z + 1.0327346262650376
* y(z) := -----------------------------------------
*                   z + 1.7997957966258356
*
* The relative is extremal at z =  .0, .22033623, 1.181958, and 5.769305.
* It is +- 1.35e-7.
*