On Sat, 12 Jun 2010 15:49:37 -0700, geremy condra wrote: > In Python3.2, calling math.erfc with a value in [-27.2, -30) raises an > OverflowError: math range error. This is inconsistent with the erfc > function from scipy (scipy.special.erfc) as well as with the C99 > function by the same name, both of which return 2. I suspect that this > is the result of the cutoff for the use of the continuing fraction > approximation of erfc beginning when abs(x) > 30, but I'm not sure. Is > this desired behavior or should I file a bug report?
Geremy, I know that as a general rule, whenever a person finds what seems to be a bug in Python (or the standard library) they should suspect their own mistake rather than a bug, but I think this is taking caution to extremes. The domain of erfc is the set of all real numbers, and the result is bounded by [0, 2]. So asking if OverflowError is desired behaviour is a bit like the fellow who bought a new car and then asked if it's supposed to catch fire when starting the engine... :) -- Steven -- http://mail.python.org/mailman/listinfo/python-list
