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Re: Representing a set of value pairs?

From: Roger L. Costello <costello@mitre.org>
Date: Sun, 20 Jul 2003 07:36:56 -0400
Message-ID: <3F1A7ED8.2C145AB2@mitre.org>
To: Stan Devitt <jsdevitt@stratumtek.com>, www-math@w3.org, "Costello,Roger L." <costello@mitre.org>

Thanks Stan.  Let me see if I understand you correctly.  Are you saying
that when defining this set in MathML:

    {i, c | c = i * 2.54}

After specifying the set contents I need to specify the "set variables"
(in this case they are "i" and "c")?  e.g., 

<set>
  <bvar>...</bvar>
  <condition>
     ...
  </condition>
  <list><ci>i</ci><ci>c</ci></list>  <-- specify set variables here
</set>

Is the purpose of:

   <list><ci>i</ci><ci>c</ci></list>

to indicate "these are the set variables"? 

Is there an advantage of using <list>...</list> rather than set, i.e.,

   <set><ci>i</ci><ci>c</ci></set>

Thanks!  /Roger


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 07:39:17 GMT

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