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Re: mover vs latin chars with diacriticals

From: Neil Soiffer <neils@dessci.com>
Date: Mon, 1 May 2006 00:59:35 -0700
Message-ID: <D1EFB337111B674B8F1BE155B01C6DD60DB799@franklin.corp.dessci>
To: "Public MathML mailing list" <www-math@w3.org>

----- Original Message -----
> From: <juanrgonzaleza@canonicalscience.com>
> To: <www-math@w3.org>
> Sent: Saturday, April 29, 2006 11:21 AM
> Subject: Re: mover vs latin chars with diacriticals
> Neil Soiffer wrote:
> [snip]
> > "=" means it is an informative comment.  Standards have
> > informative comments and normative statements.  Informative
> > comments are *not* part of the standard.  The informative
> > comment says this can be used for the newtonian derivative
> > notation, not that it should be used.
> The Unicode folks explain the "legend":
> i)  Upper case means Unicode name.
> ii)  = means alternative name
> iii)  250 means informative note.
> iv)  -> means cross reference
> et cetera.

Please see http://www.unicode.org/versions/Unicode4.0.0/ch16.pdf for a full description.  Here is an excerpt about "Aliases"

An alias (preceded by =) is an alternate name for a character. Characters may have several
aliases, and aliases for different characters are not guaranteed to be unique. Aliases are
informative and may be updated....

> > Precomposed characters  (as noted by some of the
> > places you quote and the Unicode standard) can provide a better
> > rendering.  However, they are a rendering technique and there is
> > no reason a smart MathML renderer shouldn't substitute those
> > glyph's for <mover> *if* they are available.
> Are you sure that Unicode is just a "rendering technique"?

Please read what was written.  I said that *precomposed characters* are a rendering technique.
> >> [http://www.geocities.com/chavchan/userjs/support.xml]
> >>
> >>Support for ANSI/NISO/ISO-12083 Mathematics DTD
> >>
> >> "Overscripts should not be used to produce accents, Unicode
> >> based solutions (either combining diacritical marks, or
> >> precomposed characters) are preferable in this case."
> >
> > This is one person's opinion, not what ISO-12083 says.  As far
> > as I could see, 12083 is silent on the matter.  While it is
> > informative to get another opinion on this, implying that this
> > is what 12083 says is false (at least as far as I could see in
> > 12083's math section).
> Implying that this is what 12083 says? Where?

Again, you misread what I wrote.  I was merely clarifying what you quoted as being one person's opinion, not what was contained in the 12083.
> I thought that was clear that
> [http://www.geocities.com/chavchan/userjs/support.xml]
> was a page to userjs-support by "chavchan" stored in geocities and titled
> "UserJS processors for ISO-12083 Mathematics DTD and MathML 2.0"
> I also thought that people at MathML would be able to see that ISO 12083
> was developed ***before*** Unicode. Therefore, It is really surprising
> that a MathML WG folk is claiming:
> "As far as I could see, 12083 is silent on the matter."

Of course the MathML committee members knew that 12083 was developed years before MathML.  People in the working group were very aware of its strengths and weaknesses and MathML was developed with feedback from users of 12083 (ie, publishers) as to what to avoid. I realize that English is not your first language; before you resort to insulting remarks about the intelligence of others, please take a moment to think about the more plausible explanation that maybe you have not understood what the comment was about.

12083 has "embellishments", which can be used for diacritical marks in the same way that <mover> can be used for diacritical.  My comment was that 12083 is silent on the matter which I raised -- ie, whether a character should be used or whether an embellishment should be used.

> By using MathML <munder> and <mover> instead of Unicode, one recover all
> well-known difficulties, weakness and error designs of MathML, including
> incompatibilities with CSS and DOM and all that without review real
> support of MathML in browsers. Unicode is designed for both on and off web
> usage.

There are a lot of generalities here which about problems with <mover> and <munder>.  Rather than misinterpret what you mean to say, could you please clarify "the well-known difficulties, weakness and error designs of MathML, including incompatibilities with CSS and DOM and all that without review real support of MathML in browsers".  Please list the specifics with respect to <mover> and <munder> (to which your comment applies).
> What is more, using standard Unicode one can add "semantics" (at least one
> can differentiate dieresis from a double dot), whereas the <mover> of
> MathML specification cannot.

This is both a red-herring and wrong.  
Red herring:  Presentation MathML is meant to be used for mathematical notation.  It is not meant to be used to construct linguistic modifications of characters...as several people have already replied.  Nor is it meant for writing chemical formulas (another area where you misapplied MathML and used it as evidence MathML is flawed).

Wrong:  Unicode's "COMBINING DIAERESIS" (308) has several aliases, one of which is "double derivative".  So if you feel the informative alias as "double derivate" is a good use of the code point, you have lost the distinction between the two.  If however, you use it as a diaeresis and use <mover> to represent the mathematical meaning, then you have distinguished between the two usages.

Neil Soiffer
Senior Scientist
Design Science, Inc.
~ Makers of Equation Editor, MathType, MathPlayer and MathFlow ~

Received on Monday, 1 May 2006 08:01:50 UTC

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