Message 59211 - Python tracker

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In-reply-to
Author	tim.peters
Recipients	Rhamphoryncus, christian.heimes, gvanrossum, mark.dickinson, tim.peters
Date	2008年01月04日.03:51:25
SpamBayes Score	0.17410327
Marked as misclassified	No
Message-id	<1199418685.94.0.940898681977.issue1640@psf.upfronthosting.co.za>

Content
The functionality of what was called (and I agree confusingly so) "sign()" here is supplied by "signbit()" in C99. That standard isn't free, but the relevant part is incorporated in the free Open Group standards: http://www.opengroup.org/onlinepubs/000095399/functions/signbit.html The 754 standard says NaNs have sign bits, but assigns no meaning to them. In particular, the value of the sign bit of a NaN resulting from a string->double routine applied to the string "nan" isn't defined by 754, or (AFAICT) by C99 either.

Content

The functionality of what was called (and I agree confusingly so)
"sign()" here is supplied by "signbit()" in C99. That standard isn't
free, but the relevant part is incorporated in the free Open Group
standards:
http://www.opengroup.org/onlinepubs/000095399/functions/signbit.html
The 754 standard says NaNs have sign bits, but assigns no meaning to
them. In particular, the value of the sign bit of a NaN resulting from
a string->double routine applied to the string "nan" isn't defined by
754, or (AFAICT) by C99 either.

History
Date	User	Action	Args
2008年01月04日 03:51:26	tim.peters	set	spambayes_score: 0.174103 -> 0.17410327 recipients: + tim.peters, gvanrossum, mark.dickinson, Rhamphoryncus, christian.heimes
2008年01月04日 03:51:26	tim.peters	set	spambayes_score: 0.174103 -> 0.174103 messageid: <1199418685.94.0.940898681977.issue1640@psf.upfronthosting.co.za>
2008年01月04日 03:51:25	tim.peters	link	issue1640 messages
2008年01月04日 03:51:25	tim.peters	create

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