Author skrah
Recipients mark.dickinson, skrah
Date 2009-11-07.20:41:37
SpamBayes Score 1.63366e-07
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Message-id <1257626499.13.0.928047451376.issue7281@psf.upfronthosting.co.za>
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Sorry to report so many obscure corner cases. With the combination
Opensolaris/suncc/Python3.x copysign() gives reversed results when the
second argument is a NaN. The bug is in the C99 copysign() function
(OpenSolaris/suncc), but Python2.6 seems to have a workaround: 

Python 3.2a0 (py3k:76144, Nov  7 2009, 18:50:00) [C] on sunos5
Type "help", "copyright", "credits" or "license" for more information.
>>> from math import *
>>> copysign(1.0, float("nan"))
-1.0
>>> copysign(1.0, float("-nan"))
1.0

Python 2.6.2 (r262:71600, Nov  7 2009, 19:29:52) [C] on sunos5
Type "help", "copyright", "credits" or "license" for more information.
>>> from math import copysign
>>> copysign(1.0, float("nan"))
1.0
>>> copysign(1.0, float("-nan"))
-1.0
>>>
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Date User Action Args
2009-11-07 20:41:39skrahsetrecipients: + skrah, mark.dickinson
2009-11-07 20:41:39skrahsetmessageid: <1257626499.13.0.928047451376.issue7281@psf.upfronthosting.co.za>
2009-11-07 20:41:38skrahlinkissue7281 messages
2009-11-07 20:41:37skrahcreate