Steven D'Aprano added the comment:

I have changed the algorithm for statistics.sum to use long integer summation 
of numerator/denominator pairs.

This removes the concerns Mark raised about the float addition requiring 
correct rounding. Unless I've missed something, this now means that 
statistics.sum is now exact, including for floats and Decimals.

The cost is that stats.sum(ints) is a little slower, sum of Decimals is a lot 
slower (ouch!) but sum of floats is faster and of Fractions a lot faster. 
(Changes are relative to my original implementation.) In my testing, 
algorithmic complexity is O(N) on the number of items, at least up to 10 
million items.

----------
Added file: http://bugs.python.org/file31473/statistics_newsum.patch

_______________________________________
Python tracker <rep...@bugs.python.org>
<http://bugs.python.org/issue18606>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

Reply via email to