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Re: small samples

From: Ka-Ping Yee <kpyee@aw.sgi.com>
Date: Sat, 17 Aug 1996 16:50:31 +0900
Message-Id: <321579C7.2620@aw.sgi.com>
To: Ron Whitney <RFW@math.ams.org>
Cc: w3c-math-erb@w3.org
Ron Whitney wrote:
> 
> py> rw> Item 2 / nested subscript
> py> rw> -------------------------
> py> rw>
> py> rw> TeX:            s_{i_k}
> py> rw> Wolfram:        s_i_k
> py> rw> MINSE:          s;(i;k) or s .dnidxa (i .dnidxb k)
> py>
> py> I'm not very clear on why you would need to separate the two indices
> py> by using different compounds here, but as it stands the two alternatives
> py> aren't equivalent.  Probably most equivalent to the other examples would be:
> py>
> py>     'idx(s, 'idx(i, k))        s .idx (i .idx k)        s;(i;k)
> 
> I used different notations for the indexing operation because I felt
> there might be cases where separation of the two maps would be useful.

I understand what you mean here.  I was just saying that the
undistinguished example s;(i;k) is most like the examples for
the other notations you provide, for comparison's sake.  Then
the point of providing the second example would be just to
show that such disambiguation is possible.

> I may not be following why you call the two forms I posted
> "inequivalent".  
> I would claim that the second ("s .dnidxa (i .dnidxb
> k)") is more highly disambiguated than the first

Yes.  That's all i wanted to clarify -- that the first
example would not expand to the same thing as the second.

With regard to the examples headings:

> py> Another possibly significant point to make is that, while
> py> the examples were entitled "subscript", "superscript",
[...]
> 
> Yes.  This lies at the base of some fundamental differences in
> approach.  Bruce has termed the Wolfram approach "notational"
> and MINSE "semantical".
[...]
> The reason I would choose to categorize by notation and attach
> semantics afterward is because I view the semantical problem as much
> thornier and because we know we have to come up with notation which
> meets the needs of users who wish to keep semantics in the eyes and
> ears of the beholders.

It is a fairly fundamental difference in approach, yes.  I think
that opinions vary about how difficult the semantic problem is
(i think it can be handled a piece at a time and by people in
the appropriate areas of expertise, but someone on www-html has
dismissed it as virtually impossible).
 
> Can we operate in this way, recognizing differences?  If you feel this
> closes doors, do say so.  I'm not inclined to attack semantics as
> OpenMath and Pike are doing, but I don't think I've ruled out other
> ideas of MINSE.

Yes, i think that categorizing your examples purely by presentational
constructs could be somewhat limiting.  I don't think this means that
you should just stop providing examples, but i did want to be sure
this difference was recognized and understood.

I'm curious to know in more detail what you mean by your last
sentence.  In your mind, what have you "ruled out" and "not ruled out"
among ideas from MINSE?

 
Ping (Ka-Ping Yee): Developer, Alias|Wavefront Inc. (Tokyo)
Received on Saturday, 17 August 1996 04:56:00 UTC

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