Currently provides AMOS and Faddeeva. AMOS (from Netlib) is a
portable package for Bessel Functions of a Complex Argument and
Nonnegative Order; it contains subroutines for computing Bessel
functions and Airy functions. Faddeeva allows computing the
various error functions of arbitrary complex arguments (Faddeeva
function, error function, complementary error function, scaled
complementary error function, imaginary error function, and Dawson function);
given these, one can also easily compute Voigt functions, Fresnel integrals,
and similar related functions as well.