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Groups > comp.lang.python > #106962
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| From | Peter Otten <__peter__@web.de> |
| Newsgroups | comp.lang.python |
| Subject | Re: sum accuracy |
| Date | Wed, 13 Apr 2016 19:03:06 +0200 |
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| Lines | 17 |
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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.
"""
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Re: sum accuracy Peter Otten <__peter__@web.de> - 2016-04-13 19:03 +0200
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