(j3.2006) out_of_range and sNaN

[Bill Long]

On Oct 4, 2016, at 6:41 AM, Dan Nagle <danlnagle at me.com> wrote:

> Hi,
> 
> IEEE_CLASS can touch a signaling NaN safely
> and return IEEE_SIGNALING_NAN.
> 
> What about OUT_OF_RANGE ?  If IEEE_SUPPORT_NAN has the value true,
> does OUT_OF_RANGE return true? or does it explode?

The description spells out the case for the argument X being a NaN, so I assume you area asking about the result?   The whole point (at least  my impression) of OUT_OF_RANGE is to tell the user whether the conversion of X to a type/kind specified by MOLD *would be* out of range if the conversion were attempted. The conversion is not actually done, so the chances of ?explode? are zip.  If the conversion would result in a NaN or Infinity, then the result is .true. - i.e. it is out of range. 

Cheers,
Bill



> 
> If it explodes, should it safely return false?
> I think the more useful course is to tell the user,
> but there may be other issues I haven't considered yet
> (or words I missed in 007).
> 
> Just askin'  No pressing issue here.
> If the consensus is that the words could be better,
> I'll write a paper.
> 
> --
> 
> Cheers!
> Dan Nagle
> 
> 
> 
> 
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Bill Long                                                                       longb at cray.com
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