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Re: Motion 3



  
 Dear Juergen,

 before voting Motion 3 I want to ask you:

 Does your interpretation/definition of "interval"
 excludes the possibility to consider
 a pair of two "intervals" again as an "interval"?

 I ask this question because as
we know the natural way to introduce 
negative numbers in mathematics is 
to define them as pairs of positive numbers.
This is natural because positive numbers
do not admit inverse additive.

The situation is same with intervals, and the natural 
way to interval arithmetic is to consider pairs of 
intervals again as intervals. Will the standard
prohibit such a  semantic?

As far as I remember such is the semantic involved 
in your  paper: 

Wolff v.  Gudenberg, J., Determination of Minimum Sets 
of the Set of Zeros of a Function}, Computing 24, 1980, 203--212).

Regards,

Svetoslav


====================


 > Wolff v. Gudenberg   :
 > Dear members of the working group.
  >Please note the following motion concerning the semantics of intervals
  >So it is not about structure and procedure, not to fiX the final 
 > formulation, but about contents
  >Comments welcome
  >Juergen
 
>>
>>
>> ===Motion P1788/M0003.01_Set_of_reals===
>> Proposer: Juergen Wolff von Gudenberg
>> Seconder: required
>>
>> ===Motion text===
>> The P1788 Interval arithmetic standard defines intervals as closed 
>> and connected sets  of real numbers.
>> That means that +/- Infinity may be used to denote an unbounded 
>> interval but are never considered as members of an interval.
>>
>> ===Rationale===
>> The Vienna Proposal section 1.2
>> Kulisch's position paper "Complete Interval Arithmetic"
>> The extensive discussion in the mailing list
>>