Re: Feature suggestion: sum() ought to use a compensated summation algorithm

From: Ivan Illarionov <ivan.illarionov@xxxxxxxxx>
Date: Sat, 3 May 2008 21:37:25 +0000 (UTC)

On Sat, 03 May 2008 20:44:19 +0200, Szabolcs Horvát wrote:

Arnaud Delobelle wrote:

sum() works for any sequence of objects with an __add__ method, not
just floats! Your algorithm is specific to floats.

This occurred to me also, but then I tried

sum(['abc', 'efg'], '')

Interesting, I always thought that sum is like shortcut of
reduce(operator.add, ...), but I was mistaken.

reduce() is more forgiving:
reduce(operator.add, ['abc', 'efg'], '' ) # it works
'abcefg'

--
Ivan
.

Follow-Ups:
- Re: Feature suggestion: sum() ought to use a compensated summation algorithm
  - From: Thomas Dybdahl Ahle

References:
- Feature suggestion: sum() ought to use a compensated summation algorithm
  - From: Szabolcs Horvát
- Re: Feature suggestion: sum() ought to use a compensated summation algorithm
  - From: Arnaud Delobelle
- Re: Feature suggestion: sum() ought to use a compensated summation algorithm
  - From: Szabolcs Horvát

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