
Boost : 
From: Gabriel Dos Reis (Gabriel.DosReis_at_[hidden])
Date: 20001020 06:43:24
"David Abrahams" <abrahams_at_[hidden]> writes:
  Original Message 
 From: "Gabriel Dos Reis" <Gabriel.DosReis_at_[hidden]>


 >
 > Actually, the rules are simple and they should not be hard to follow..
 >
 > If the system is conforming to LIA then the floating point values set is
 > symmetric because LIA's model is signmagnitude.
 >
 > For nonLIA system (actually, only systems using radiccomplement
 > representation should exhibit that behaviour) there is a notion of
 > mostnegative value which is quite distinct from what one calls min()
 > in case of floating point values.
 >
 > Yes, the terminology is quite confusing, but I weren't there when
 > LIA1 was adopted as an international standard.


 Gaby,

 I think you and Matt have both missed my point (I explained this to Matt in
 a private email).
Probably because the original question didn't reflect what you
intended? ;)
 ... Suppose you have an arbitrary type T (possibly
 userdefined) for which numeric_limits<> is specialized. How do you find the
 minimum representable value?
If is an integer type, then you're done; else you have a floating
point type and the canonical model is signmagnitude and you take
max(). Yes that assumes only integer and floating point types are
supported by numeric_limits<>.
Floating point types which don't use signmagnitude aren't covered 
actually I don't think they are widely used, since LIA or IEEE models
tends to be the standard; both models use signmagnitude.
Am I still missing your point? :)
 Gaby
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