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Re: Motion 46: finalise interval literals, amendments NO RATIONALS



20130402Level1and2textV7.1Sent.pdf says about function
text2interval(2): String -> T .
You say about function
text2intval(s): String -> FRbar .

Do they are equivalent when T = FRbar ?

  -Dima

----- Исходное сообщение -----
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Копия: rbk5287@xxxxxxxxxxxxx, nedialk@xxxxxxxxxxx, j.d.pryce@xxxxxxxxxx, stds-1788@xxxxxxxxxxxxxxxxx
Отправленные: Четверг, 11 Июль 2013 г 13:22:38 GMT +04:00 Абу-Даби, Маскат
Тема: Re: Motion 46: finalise interval literals, amendments NO RATIONALS

Baker, John
1.   it is more than that simple motion.
I would further require only the following

" P1788 shall provide a constructor, (converter, transformer, function)
text2intval : String -> FRbar,
                         s \mapsto X   where s is a string representing 
an interval Y
such that Y    \subseteq  X and  for all Z \in FRbar, Y \subsetq Z ==> X 
\subseteq Z

If the underlying type is IEEE754 conformant and provides the 
covertFormat function with rounding, then X =[xlo,xup] can be computed by
  xlo = convertFromDecimalCharacter_down("ylo")
  xup = convertFromDecimalCharacter_up("yup")
where "ylo","yup"  are the corresponding parts of the string s
"
3. The various  nice representations of interval literals should only be 
recommended not mandatory
So I suggest to replace the "shall"  by  "should"
4. There is a typo in 11.11.2
empty instead of entire in the last line
5. In its current form the motion is too losely worded.
Here is what I put on the website:
===== Motion ======
The syntax and semantics of interval literals shall be - as specified in 
Draft 7.1 circulated as 20130402Level1and2textV7.1Sent.pdf; - with the 
addition of the singleton interval form [x] which is equivalent to [x,x]. "
section numbers are required IMHO here 11.11.1. is the main part of the 
corresponding p1788 text,
  but also11.11.2, 11.11.8, 12 are related

6. delete the last paragraph
p1788 is about intervals not about symbolic computing

"The standard will not at this stage include a facility for named 
constants such as pi to be included in the definition of an interval 
literal."

Jürgen

Am 10.07.2013 22:13, schrieb Ralph Baker Kearfott:
> Juergen, Ned,
>
> Do we need a simple motion stating "P-1788 will not specify
> items dealing rational arithmetic" (or other clear phrasing)?
> That would resolve the issue, but would take several weeks to
> process.
>
> Baker
>
> On 07/10/2013 04:47 AM, J. Wolff von Gudenberg wrote:
>> P1788
>> I strongly support Ned's argument against rational endpoints in P1788
>> Jürgen 
>

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