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Re: default for ma@symmetric

From: Neil Soiffer <NeilS@dessci.com>
Date: Sat, 8 Feb 2014 12:57:34 -0800
Message-ID: <CAESRWkAO9ettwsXn2Kj-iD9Ojr4g64ZEx9T1NeM5Osm_3aMEjQ@mail.gmail.com>
To: "Davide P. Cervone" <dpvc@union.edu>
Cc: "www-math@w3.org" <www-math@w3.org>
Speaking for myself and not the group, I believe the default was meant to
be 'true' and that the 'false' value is a copy/paste error from the entry
above. In MathML 1 and 2, the default was "true".

The operator dictionary only lists a value when the value is true -- if a
value isn't given and it is relevant, then it's value is false. There is
some text a few paragraphs above that explain that.

The word "glossary" is a typo of some kind. It might have been something
tied to the glossary markup for "axis" a few words before it. Thanks for
catching that.

>From a practical point of view, the default is likely irrelevant for an
implementation. If you know how to stretch a character, you probably should
have a operator dictionary entry for that character, and the symmetric
property default should be decided upon based on that character's usage.
The operator dictionary in appendix C is non-normative and definitely not
complete.

Neil Soiffer
Senior Scientist
Design Science, Inc.
www.dessci.com
~ Makers of MathType, MathFlow, MathPlayer, MathDaisy, Equation Editor ~




On Sat, Feb 8, 2014 at 11:22 AM, Davide P. Cervone <dpvc@union.edu> wrote:

> According to the MathML3 spec
>
>         http://www.w3.org/TR/MathML3/chapter3.html#presm.mo.attrs
>
> the value for the "symmetric" attribute of the mo element is "set by
> dictionary (false)", but in the description just below that is says "Note
> that the default is true".  So I'm confused about which it should be.  If
> the operator dictionary doesn't specify a value, should it be symmetric or
> not?  I'm guessing it is false, since the dictionary explicitly gives some
> stretchy elements that symmetric property, but not others (e.g., vertical
> bars and vertical arrows are not listed as symmetric).
>
> Also, what does the work "glossary" in "glossary Note that the default is
> true" mean (in the table for the attributes of mo)?  A typo?
>
> Davide
>
Received on Saturday, 8 February 2014 20:58:02 UTC

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