[SciPy-dev] scipy.special.bdtrik bug (ticket #1076)

[Anne Archibald]

Hi,

I was recently doing some calculations with scipy.stats.binom().ppf
and found a nasty bug ( http://projects.scipy.org/scipy/ticket/1076 ).
If the binomial probability is tiny, totally wrong answers emerge. The
problem turns out to be in the function scipy.special.bdtrik. There's
no documentation anywhere about what this is supposed to do, but from
context it's pretty clear it exists to calculate this value. It's a
cephes function, and I got a little lost trying to track down its
implementation. Maybe someone who's more familiar with cephes could
point me to the code, and how to put it in __all__?

Thanks,
Anne