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Re: Representing a set of value pairs?

From: Bill Naylor <Bill.Naylor@mcs.vuw.ac.nz>
Date: Mon, 21 Jul 2003 10:52:02 +1200 (NZST)
To: Stan Devitt <jsdevitt@stratumtek.com>
cc: "Roger L. Costello" <costello@mitre.org>, www-math@w3.org, davidc@nag.co.uk, jhd@cs.bath.ac.uk
Message-ID: <Pine.SOL.4.51.0307211034430.2139@debretts.mcs.vuw.ac.nz>


I think this is an interesting example. I would suggest that the meaning
of these examples could be made more precise by using the definitionURL
attribute, attached to the <ci> inside the bvar, to point to OpenMath CDs:

<set>
  <bvar><ci
defintionURL="http://www.openmath.org/cd/units_imperial2#inch">i</ci></bvar>
  <bvar><ci
defintionURL="http://www.openmath.org/cd/units_metric2#centimeter">c</ci></bvar>
  <condition>
  <apply><eq/>
    <ci>c</ci>
    <apply><times/>
      <ci>i</ci>
      <cn>2.54</cn>
    </apply>
  </apply>
  </condition>
  <list><ci>i</ci><ci>c</ci></list>
</set>

at least I would have, until I noticed that these symbols do not exist :-!
David, James: do you think that these *_imperial2, *_metric2 cds should be
written. This example from R. Costello provides a pretty clear raison
d'ettre for them, I don't see how his example could be marked up otherwise
without using Private cds?

Bill

> >
> >Stan Devitt wrote:
> >
> >
> >>This type of set constructor should have a final argument which is
> >>a sample of the thing being constructed as in
> >>
> >><set>
> >>  <bvar><ci>i</ci></bvar>
> >>  <bvar><ci>c</ci></bvar>
> >>  <condition>
> >>  <apply><eq/>
> >>    <ci>c</ci>
> >>    <apply><times/>
> >>      <ci>i</ci>
> >>      <cn>2.54</cn>
> >>    </apply>
> >>  </apply>
> >>  </condition>
> >>  <list><ci>i</ci><ci>c</ci></list>
> >></set>
> >>
> >>They should be grouped in some way, for example, using a set,
> >>list or vector.
> >>
> >>Stan Devitt
> >>StratumTek
> >>
> >>Roger L. Costello wrote:
> >>
> >>
> >>
> >>>Hi Folks,
> >>>
> >>>Suppose that I want to represent the set of all inch/centimeter pairs,
> >>>e.g,
> >>>
> >>>  {i, c | c = i * 2.54}
> >>>
> >>>Examples in this set include:
> >>>
> >>>  (1.0, 2.54), (2.0, 5.08), etc
> >>>
> >>>Is this the correct way to represent this set in MathML:
> >>>
> >>><math>
> >>>   <declare type="set">
> >>>       <ci>S<ci>
> >>>       <set>
> >>>           <bvar><ci>i</ci></bvar>
> >>>           <bvar><ci>c</ci></bvar>
> >>>           <condition>
> >>>               <apply>
> >>>                   <eq/>
> >>>                   <ci>c</ci>
> >>>                   <apply>
> >>>                       <times/>
> >>>                       <ci>i</ci>
> >>>                       <cn>2.54</cn>
> >>>                   </apply>
> >>>               </apply>
> >>>           </condition>
> >>>       </set>
> >>>   </declare>
> >>></math>
> >>>
> >>>I think that this is correct.  My only hesitation is that perhaps I need
> >>>parentheses around (i,c)?  e.g.,
> >>>
> >>>     {(i, c) | c = i * 2.54}
> >>>
> >>>And likewise in the MathML representation place parentheses?  /Roger
> >>>
> >>>
> >>>
> >>>
> >>>
> >
> >
> >
>
>
>
Received on Sunday, 20 July 2003 18:53:18 GMT

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