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From: Peter Otten <__peter__@web.de>
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Subject: Re: sum accuracy
Date: Wed, 13 Apr 2016 19:03:06 +0200
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Xref: csiph.com comp.lang.python:106962

Robin Becker wrote:

> Does anyone know if sum does anything special to try and improve accuracy?
> My simple tests seem to show it is exactly equivalent to a for loop
> summation.

If you are worried about accuracy and your values are floating point numbers 
use math.fsum():

"""
fsum(...)
    fsum(iterable)
    
    Return an accurate floating point sum of values in the iterable.
    Assumes IEEE-754 floating point arithmetic.
"""