On Tue, Aug 30, 2011 at 11:46 AM, Spectral One <ghostwriter402@gmail.com> wrote:
Wandering about, looking up statistics info for a program I was writing, I found a recommendation to add various useful 'special functions' to C's math library: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1069.pdf
The arguments in that paper make a lot of sense to me, and apply well to Python. They came up with a good list, IMnsHO. I'd recommend implementing this list in some form as library functions in Python.
Blindly copying wouldn't end up particularly 'Pythonic;' tweaking the API is required. Some of the selection choices, such as returning real only, ought to be reevaluated, for example. Obviously, any of the decisions to keep things C-like rather than object-oriented ought to shift, as well.
Function names are only important as far as they are clear. I suggest naming per <general category><specific case> e.g. distribution_t(), or dist_F(), and include modification for algebraic order, as well, so gamma() and log_gamma(). That said, anything clear is fine.
Thoughts on the matter? I noticed that the math library in 2.7+ added the gamma and log(gamma) functions, already, which was nice. Obviously, most, if not all, are already present in extensions modules such as NumPy, but there is value in having these things built into the language. "Batteries included, "and all that.
By the by, if that is far too much for one suggestion, then please just treat this as a suggestion to add just the incomplete beta function. (P-values for binomial, F, and t are all nice, too, though with inc. beta, they aren't terrible to generate. I really think they should be included in the standard library.)
I'm not sure that many people who could make tons of use from statistical functions don't already have cause to be using numpy/scipy. I would certainly be unfortunate if having a little more statistics functionality in the stdlib discouraged people who should be using numpy from doing so. "Batteries included" has always been a bit of an oversell, and as a Python user I don't have any expectation of being able to do fairly-specialized work without third-party modules, nor do I think it's necessarily a net gain for Python if I could. -0 Mike