Guido van Rossum wrote:
> Guido van Rossum added the comment:
> 
> i suggest abandoning any attempts at implementing math ourselves.  I
> also suggest not combining this with #1635 but reviewing and
> (eventually) applying the latter first.

How do you like a compromise? I rip out the new functions for the math
module except isnan(), isinf() and sign(). The new patch would contain
the inf and nan roundtrip plus the helper methods.

Mark is right. My naive functions are a numerical nightmare for small
and large numbers. I copied them from my math handbook 'cause I couldn't
find solid implementations in my numerical handbook. It contains all
sort of algorithms for approximations, ODE, PDE, FFT but no sample of
the inverse hyperbolic functions.

We could reuse the functions from the BSD libm. They are used in
numerous C runtime libraries (BSD, Mac OS X, uclibc).
http://packages.e.kth.se/common/src/os/NetBSD/1.3.2/lib/libm/src/

Christian