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Re: RE: The limits of XML mean the limits of my data world

• From: "Imsieke, Gerrit, le-tex" <gerrit.imsieke@le-tex.de>
• To: xml-dev@lists.xml.org
• Date: Mon, 30 May 2022 08:13:22 +0200

>   > XML may not be good at representing concurrency (overlap just on one-dimension -- time).
>
>   Is this an example of concurrency?

Concurrency is any overlap on the time axis.

A good example is the scores used by the director of an orchestra. Because of the concurrency of playing of the different groups of musical instruments within an orchestra, their scores are printed not in one continuous linear line, but on many parallel horizontal lines one below the other as the musical durations of non-paused play of these different instrumental groups overlap horizontally, where the horizontal axis from left to write expresses the time.

Say you have a violin and a clarinet. The violin plays a single tone in the interval [t1, t2] and the clarinet plays another tone in the interval [t3, t4]. And   t1 < t3 < t2 < t4    or    t3 < t1 < t4 < t2.

With XML one cannot represent such partial overlaps, but overlaps where one of the durations completely contains the other (which is not generally the rule in music), can be represented by two elements, the second of which is contained in the scope of the first: t1 <= t3 < t4 <= t2   or t3 <= t1 < t2 <=t4


On Sun, May 29, 2022 at 12:08 PM Roger L Costello <costello@mitre.org <mailto:costello@mitre.org>> wrote:

Peter wrote:

> overlap can be expressed but not represented

I am not clear what you mean by "overlap". Is this an example of
overlap:

Classroom1 is used for teaching math, science, and writing.
Classroom2 is used for teaching art, history, and writing.

There is overlap between the topics taught in classroom1 and
classroom2 -- writing. Is that what you mean by "overlap"?

If so, can't that be expressed in XML something like this:

<Classrooms>
    <Classroom1>
        <ClassesTaught>
            <Class>math</Class>
            <Class>science</Class>
            <Class>writing</Class>
        </ClassesTaught>
    </Classroom1>
    <Classroom2>
        <ClassesTaught>
            <Class>art</Class>
            <Class>history</Class>
            <Class>writing</Class>
        </ClassesTaught>
    </Classroom2>
</Classrooms>

Dimitre wrote:

> XML may not be good at representing concurrency (overlap just on
one-dimension -- time).

Is this an example of concurrency?

During times 1 - 3 John Doe is driving from Boston to NYC and during
the same times Sally Smith is driving from LA to San Diego.

Is that an example of what you mean? If so, can't that be expressed
in XML something like this:

<DrivingTrips>
    <Person>
        <Name>John Doe</Name>
        <Itinerary>
            <Start>Boston</Start>
            <End>NYC</End>
        </Itinerary>
        <DriveTimes>
            <Time1/>
            <Time2/>
            <Time3/>
        </DriveTimes>
    </Person>
    <Person>
        <Name>Sally Smith</Name>
        <Itinerary>
            <Start>LA</Start>
            <End>San Diego</End>
        </Itinerary>
        <DriveTimes>
            <Time1/>
            <Time2/>
            <Time3/>
        </DriveTimes>
    </Person>
</DrivingTrips>

Peter said:

> CSV is better at expressing row-and-column type data.

That might well be true, but it is possible to express
row-and-column concepts in XML. That is, the row-and-column concept
in not outside the realm of concepts expressible by the XML language.

> Various forms of database are better at expressing other layouts
of atomic and relational data.

Again, that might well be true but the concept of a table is
expressible in XML.

Thank you Peter, Dimitre, and Gerrit but you haven't (yet) convinced
me that there are concepts that are outside the realm of concepts
expressible using the language called XML.

A friend of mine is Chinese and today I asked her: "Are there
concepts that you can express in English that you cannot express in
Chinese?" She responded, "Yes, there are concepts in English for
which there is no equivalent in Chinese." (The reverse is also true
-- there are concepts that can be expressed in Chinese that cannot
be expressed in English.)

Are there concepts in data language XYZ that cannot be expressed in
the data language we call XML? What are the boundaries of the
language we call XML, in terms of concepts that can be expressed?
How does the XML language bound (limit) ones thinking about data?

/Roger

• Follow-Ups:
  • Re: RE: The limits of XML mean the limits of my data world
    • From: Dimitre Novatchev <dnovatchev@gmail.com>

• References:
  • The limits of XML mean the limits of my data world
    • From: Roger L Costello <costello@mitre.org>
  • RE: The limits of XML mean the limits of my data world
    • From: Roger L Costello <costello@mitre.org>
  • Re: RE: The limits of XML mean the limits of my data world
    • From: Dimitre Novatchev <dnovatchev@gmail.com>