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



All, 

I do not have a strong opinion either way. The only comment I would make is to give simplicity 
higher priority than formal relations between the two standards. 

Regards, 
Ned
> On Oct 14, 2015, at 8:54 AM, Ralph Baker Kearfott <rbk5287@xxxxxxxxxxxxx> wrote:
> 
> All,
> 
> I am for including cancelMinus and cancelPlus, for practical
> reasons:  (1) I have found them useful when "updating"
> sums by removing previously added terms, such as in the
> interval Gauss--Seidel method; (2) It doesn't seem to add
> complexity to the "simplified" standard.
> 
> Of course, there may be counter arguments associated with them
> not being a part of a closed system, etc.  I'm "all ears."
> 
> Baker
> 
> On 10/12/2015 09:30 AM, Nathalie Revol wrote:
>> 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
>>>> ---------------------------------------------------------------
>>>> 
>>>> 
>> 
>> ------------------------------------------------------------------------------------------------------------
>> 
>>   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/
>> 
>> ------------------------------------------------------------------------------------------------------------
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
> 
> 
> -- 
> 
> ---------------------------------------------------------------
> 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
> ---------------------------------------------------------------