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Ray Donnelly 96fc528397 sqrt: Fix NaN propagation for IEEE Std 754-2008
The R language has some hacks specifically for mingw-w64 that
were caused by our handling of NaNs in sqrt(x). R uses a
special valued NaN to mean 'Not Available' and expects it to
be retained through various calculations. Our sqrt(x) doesn't
do this, instead it normalises such a NaN (retaining sign).

From:

http://wwwf.imperial.ac.uk/~drmii/M3SC_2016/IEEE_2008_4610935.pdf

"6.2.3 NaN propagation

An operation that propagates a NaN operand to its result and
has a single NaN as an input should produce a NaN with the
payload of the input NaN if representable in the destination
format."

There might even be a slight speed-up from this too.

Thanks to Duncan Murdoch for finding the reference.
2016-08-22 14:17:58 +02:00
..
2016-08-17 10:58:04 +02:00
2012-11-23 13:22:47 +00:00
2013-11-07 00:19:52 +00:00
2012-11-23 13:22:47 +00:00
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2012-11-23 13:22:47 +00:00
2013-11-07 00:19:52 +00:00
2012-11-23 13:22:47 +00:00
2016-05-24 10:25:18 +02:00

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