[Python-Dev] PyObject_RichCompareBool identity shortcut

Wed Apr 27 18:40:04 CEST 2011

On 2011年4月27日, Antoine Pitrou wrote:
> Isaac Morland <ijmorlan at uwaterloo.ca> wrote:
>>>> Python could also provide IEEE-754 equality as a function (perhaps in
>> "math"), something like:
>>>> def ieee_equal (a, b):
>> 	return a == b and not isnan (a) and not isnan (b)
>> +1 (perhaps call it math.eq()).

Alexander Belopolsky pointed out to me (thanks!) that isnan is implemented 
in C so my caveat about the implementation of isnan is not an issue. But 
then that made me realize the ieee_equal (or just "eq" if that's 
preferable) probably ought to be implemented in C using a floating point 
comparison - i.e., use the processor implementation of the comparison 
operation..
Isaac Morland			CSCF Web Guru
DC 2554C, x36650		WWW Software Specialist