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Author noam
Recipients christian.heimes, gvanrossum, nascheme, noam, rhettinger, tim.peters
Date 2007-12-11.23:07:39
SpamBayes Score 0.22654349
Marked as misclassified No
Message-id <>
In-reply-to <>
If I understand correctly, there are two main concerns: speed and
portability. I think that they are both not that terrible.

How about this:
* For IEEE-754 hardware, we implement decimal/binary conversions, and
define the exact behaviour of floats.
* For non-IEEE-754 hardware, we keep the current method of relying on
the system libraries.

About speed, perhaps it's not such a big problem, since decimal/binary
conversions are usually related to I/O, and this is relatively slow
anyway. I think that usually a program does a relatively few
decimal/binary conversions.
About portability, I think (from a small research I just made) that
S90 supports IEEE-754. This leaves VAX and cray users, which will have
to live with a non-perfect floating-point behaviour.

If I am correct, it will let 99.9% of the users get a deterministic
floating-point behaviour, where eval(repr(f)) == f and
repr(1.1)=='1.1', with a speed penalty they won't notice.
Date User Action Args
2007-12-11 23:07:40noamsetspambayes_score: 0.226543 -> 0.22654349
recipients: + noam, gvanrossum, tim.peters, nascheme, rhettinger, christian.heimes
2007-12-11 23:07:40noamlinkissue1580 messages
2007-12-11 23:07:39noamcreate