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<== Date ==> <== Thread ==>

Subject: Re: Not-a-number (nan) issues
From: Till Straumann <[email protected]>
To: Kay-Uwe Kasemir <[email protected]>
Cc: Jeff Hill <[email protected]>, "'EPICS Tech Talk'" <[email protected]>
Date: Fri, 08 Oct 2004 13:43:28 -0700
I just wanted to point out that while
NaN should certainly not be written to a device,
*reading* NaN from a PV makes perfect sense to
me and is in fact a very useful and IMO legal way
to indicate e.g., that some numbers in an array
are invalid (while others may be good and it
hence doesn't make sense to mark the entire PV
status invalid).

IMO NaN should be handled at the source
(you restore program shouldn't try to send NaN)
and/or destination (don't write NaN to device)
but otherwise propagated (e.g. calc record)

-- Till


References:
RE: Not-a-number (nan) issues Jeff Hill
Re: Not-a-number (nan) issues Kay-Uwe Kasemir

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