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Author mark.dickinson
Recipients BTaskaya, lemburg, mark.dickinson, pablogsal, rhettinger, stutzbach, tim.peters, vstinner, xdegaye
Date 2019-12-08.20:28:00
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1575836881.44.0.404510292154.issue38992@roundup.psfhosted.org>
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So if I'm understanding correctly, the cause of the issue is that the value `1.7**(i+1)` computed in the last iteration (i=999) of the list comprehension doesn't exactly match the `-1.7**1000` value, because the former is computed at runtime using the libm's pow, while the latter is constant-folded and likely uses something more accurate than `pow`.

I think it should be easy to rewrite the test so that it precomputes the powers of `1.7`, and then makes sure to use those computed values (i.e., so that we're only computing `1.7**1000` once rather than twice, eliminating the possibility of getting different results).
History
Date User Action Args
2019-12-08 20:28:01mark.dickinsonsetrecipients: + mark.dickinson, lemburg, tim.peters, rhettinger, vstinner, stutzbach, xdegaye, pablogsal, BTaskaya
2019-12-08 20:28:01mark.dickinsonsetmessageid: <1575836881.44.0.404510292154.issue38992@roundup.psfhosted.org>
2019-12-08 20:28:01mark.dickinsonlinkissue38992 messages
2019-12-08 20:28:00mark.dickinsoncreate