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<== Date ==> <== Thread ==>
Subject: calc/calcout and NAN
From: Korhonen Timo <[email protected]>
To: [email protected]
Date: Tue, 26 Mar 2002 16:15:35 +0100
Hello all,

I was implementing some calculations with calcout records and
faced the following problem: with certain input values, the
result from the formula is NAN (not a number.) However, there
is no indication from the record itself that something is wrong.
(medm can display an INF but does not react to NAN.)

I would like to be able to raise an alarm (INVALID) if the result
from the calculation is NAN (at least, and maybe also for INF).

A quick try to modify the return from calcPerform (libCom/calc/calPerform.c)so that

instead of (line 514)

return(0);

I made a simple check:

return(isnan(*presult));

and that seemed to give the effect that I wanted.

Does this look like a reasonable thing to do?

Timo

--
Timo Korhonen PSI (Paul Scherrer Institut), SLS
CH-5232 Villigen PSI
tel + 41- 56 3103262 fax + 41 - 56 310 3151
e-mail: [email protected]

Replies:
Re: calc/calcout and NAN Marty Kraimer
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