[Om] How to translate csymbol/@definitionURL [Re: OpenMath 2010]

David Carlisle davidc at nag.co.uk
Fri Jul 16 13:04:16 CEST 2010

On 16/07/2010 11:52, Christoph LANGE wrote:

>> but it's not deprecated (you can't deprecate something that was never there)
>> the attribute isn't in Strict MathML because it isn't in OpenMath.
> … and I interpreted it as a de facto "deprecation" because from a
> content-oriented point of view my impression is that new tools will rather use
> strict CMML, whereas pragmatic CMML was rather kept for historical and
> political reasons.

One of the reasons for removing all mention of "pragmatic" from MathML3 
was precisely to avoid the negative connotations of the word pragmatic, 
so people wouldn't get that impression.

 >  So from that point of view anything that is not
> expressible in strict CMML seems deprecated to me.

Not at all.

>  But that objection was
> based on the wrong assumption that definitionURLs that don't fit into the
> CDBase/CD/Name schema wouldn't be expressible at all in strict CMML.

all attributes are translated even "unknown" attributes in foreign 
namespaces, which are allowed in mathml but not in the om syntax (and so 
not in strict content mathml) , where they are translated to openmath 
attributions using an "attribute" csymbol.
> Note that I was not concerned about the @definitionURL _attribute_.  It is
> perfectly clear to me that strict CMML has the CD/name syntax to express the
> same, but my point was that CD/name cannot express the same as @definitionURL.
> Once you start thinking about linking OpenMath CDs to other datasets using
> URIs (e.g. the DLMF, Paul's notation census, DBpedia, etc.), see my OM
> workshop talk on Linked Data, there will be URIs that don't fit into the
> CDBase/CD#name schema.

Openmath already has a rich annotation mechanism though, which ought to 
be able to handle that.
> Suppose we want to say: transc1#sin is the same as
> http://dlmf.nist.gov/...#sin, and suppose we want to say: the notation census
> entries for transc1#sin are at http://wiki.math-bridge.org/...#sin.  OpenMath
> does not really have a way of "linking" to things,

You can specify the URI in openmath attributions. Of course it would be 
up the the relevant phrasebook that to encode that the attributions are 
URIs to be used in certain ways. saying Openmath doesn't have a way of 
expressing these things is like saying it doesn't have a way of 
expressing plus. It's true or false, depending on your point of view.

>> MathML DefinitionURL in general (if it doesn't point to a CD)
>> corresponds to an OpenMath annotation using a symbol "definitionurl" in
>> some CD and a OMstring to hold the URI.
> Aha!  I wasn't aware of that.  But this is specified nowere in the MathML 3
> spec, is it?

yes the rules in 4.6 should write any legal content mathml into strict 
content mathml.

> My understanding was that pragmatic CMML

that P word again. don't use it, it confuses the issue.

 > is not more expressive
> than strict CMML, i.e. that for everything you can express in pragmatic CMML
> there is a well-defined translation to strict CMML somewhere in the spec.
> Otherwise human guesswork would be involved, and that would kill
> machine-understandability.
> And how would it work?  You can only attribute something that is
> an OpenMath object, so how would you say "this is something that has a
> definitionURL"?


step 9b or 9c depending on whether the definitionurl is pointing at an 
OM CD symbol.


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