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discussion period begins for Motion P1788.1/M002.01: Required operations



Dear Colleagues,

as Dmitry has moved this motion and Evgenija has seconded it,
(thank you to both of them), this is Motion P1788.1/M002.01:
the discussion period now begins and will end November 2nd.

Best regards
	Nathalie

> On 12 Oct 2015, at 16:17, Evgenija Popova <epopova@xxxxxxxxxx> wrote:
> 
> I second the motion "Required Operations".
> 
> Evgenija Popova
> 
> Institute of Mathematics and Informatics
> Bulgarian Academy of Sciences
> 
>> P-1788:
>> 
>> Does someone second this motion?
>> 
>> Baker (acting as chair)
>> 
>> On 10/12/2015 07:02 AM, Dmitry Nadezhin wrote:
>>> 
>>> Motion "Required Operations".
>>> 
>>> Operations required in all flavors of the standard IEEE 1788-2015
>>> are required also in the simplified standard P1788.1 .
>>> 
>>> Specifically, 4 operations missed in the initial draft are required
> in P1788.1:
>>> - arithmetic operations
>>>  roundTiesToEven(x)
>>>  roundTiesToAway(x)
>>> - cancellative addition and subtraction
>>>  cancelPlus(x,y)
>>>  cancelMinus(x,y) .
>>> 
>>> -----------------
>>> 
>>> Rationale.
>>> 
>>> This (together with better conformance of interval literals) permits
>>> more formal relation between IEEE 1788-2015 and P1788.1 .
>>> It makes P1788.1 become a flavor of IEEE 1788-2015
>>> though text of P1788.1 doesn't need to mention flavors.
>>> If P1788.1 satisfies requirements of IEEE 1788-2015 flavor without
> any exemptions
>>> it starts a good tradition of adding new flavors to IEEE 1788-2015.
>>> 
>>> The specification of roundTiesToXXX(x) and specification
> cancellative operations
>>> doesn't add too much text to the P1788.1 .
>>> 
>>> There are simple implementations of these functions.
>>> 
>>> A possible implementation of roundTiesToXXX(x) operations can be
> found here:
>>> 
> https://java.net/projects/jinterval/sources/svn/content/trunk/jinterval/p1788-launcher-java/src/main/resources/net/java/jinterval/p1788/integerFuns.c?rev=379
> .
>>> And Michel Hack wrote how to do it simpler:
>>> http://grouper.ieee.org/groups/1788/email/msg08423.html .
>>> 
>>> There are subtleties in implementation of cancellative operations
>>> when the answer is nearly a one-point interval (or nearly undefined).
>>> See notes in subsection 12.12.5 of IEEE 1788-2015.
>>> Nevertheless, Marco Nehmeier suggested a solution:
>>> http://grouper.ieee.org/groups/1788/email/msg07858.html .
>>> 
>>> --------------
>>> 
>> 
>> 
>> -- 
>> 
>> ---------------------------------------------------------------
>> Ralph Baker Kearfott,   rbk@xxxxxxxxxxxxx   (337) 482-5346 (fax)
>> (337) 482-5270 (work)                     (337) 993-1827 (home)
>> URL: http://interval.louisiana.edu/kearfott.html
>> Department of Mathematics, University of Louisiana at Lafayette
>> (Room 217 Maxim D. Doucet Hall, 1403 Johnston Street)
>> Box 4-1010, Lafayette, LA 70504-1010, USA
>> ---------------------------------------------------------------
>> 
>> 

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  Nathalie Revol                                                  INRIA Grenoble - Rhone Alpes
  LIP - projet AriC                                                tel: (33) 4 72 72 84 36
  Ecole Normale Superieure de Lyon            fax: (33) 4 72 72 80 80
  69364 Lyon Cedex 07, France                     Nathalie.Revol@xxxxxxxxxxx
                               http://perso.ens-lyon.fr/nathalie.revol/

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