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Re: Samples from the Internet

From: <juanrgonzaleza@canonicalscience.com>
Date: Mon, 27 Nov 2006 07:58:50 -0800 (PST)
Message-ID: <3722.217.124.88.143.1164643130.squirrel@webmail.canonicalscience.com>
To: <davidc@nag.co.uk>
Cc: <www-math@w3.org>

David Carlisle said:
>
>
>> For instance how can <csymbol> be intended to denote symbols with an
>> _external_ definition if the definition location doesn't matter at the
>> same time.
>
> perhaps we have a prior agreement that if you send me
> <csymbol>C02AHF</csymbol>
> that I'll calculate the roots of a quadratic, If you send the expression
> to another system, then most other systems just get to know it's some
> function defined externally, but that is still useful information,
> compared to just using C02AHF as a variable name, as would happen with
> ci. You could perhaps add
> http://www.nag.co.uk/numeric/FL/manual/xhtml/C02/c02ahf.xml
> as a definition URL to give other people an indication as to where that
> function is defined, but another mathml system is unlikely to be able to
> interpret that page.

Interesting discussion but is not i asked.

I asked does the definition location matters or not for selecting
<csymbol> over <ci>?

>
>> I am just curious, what is the difference between
>>
>> <sin/>
>>
>> <csymbol
>> definitionURL="http://www.w3.org/TR/MathML2/appendixc.html#cedef.sin
>> ">sin</csymbol>
>>
>> <ci
>> definitionURL="http://www.w3.org/TR/MathML2/appendixc.html#cedef.sin
>> ">sin</ci>
>
> they probably are all intended to denote the same function, so one
> answer to your question is "no difference", but any MathML system has
> knowledge that the first one denotes the sin function, whereas unless
> the system can read and interpret english html text (unlikely) or
> special case URI references to appendix C of the spec (possible) a
> system will not autmatically know that the second and third denote the
> sin function.

Then <ci> and <csymbol> are redundant each other, because for each
<csymbol i can write a <ci definitionURL>.

Other guy agreed that <sin/> and

<csymbol
definitionURL="http://www.w3.org/TR/MathML2/appendixc.html#cedef.sin
">sin</csymbol>

both represent same mathematical function and can be used in all the same
places. But apparently he think no the same about the third case.

> If you are writing mathml, then if your identifier denotes a symbol with
> a fixed external definition, use csymbol, unless you also need to target
> MathMl1 readers, in which case use ci. If your identifier denotes an
> object without a fixed external definition use ci.

Thanks by recommendation. Another i received was:

"Thus, <csymbol/> would be used to reference known or specific constants
or functions - possibly defined in the containing document, or even in the
MathML spec - the definition location doesn't matter."

"To apply the same function to a specific defined constant (possibly
defined in the containing document)

<apply>
    <csymbol definitionURL="thePlaceWhereThisfunctionIsDefined">F</csymbol>
    <csymbol definitionURL="MyFavouriteSymbolicConstant">k</csymbol>
</apply>"

Are not both contradictory recommendations?
Received on Monday, 27 November 2006 16:01:25 GMT

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