# Re: Stretchy equal sign for commutative diagrams

From: Neil Soiffer <NeilS@dessci.com>
Date: Tue, 26 Mar 2013 11:19:54 -0700
Message-ID: <CAESRWkBBb3a-G2HXrHjaf2giG4fKkSkDyDzpBKVkiCvcXaN5MA@mail.gmail.com>
To: Frédéric WANG <fred.wang@free.fr>
Cc: "www-math@w3.org" <www-math@w3.org>
Sorry for joining this late.  MathPlayer currently can make use of:

COMBINING DOUBLE LOW LINE' (U+0333)
COMBINING EQUALS SIGN BELOW' (U+0347)
COMBINING DOUBLE OVERLINE' (U+033F)
DOUBLE LOW LINE' (U+2017)

I don't think any of them are stretchy by default.

Adding '=' would (I think) be very simple.

Neil

On Sat, Mar 23, 2013 at 8:02 AM, Frédéric WANG <fred.wang@free.fr> wrote:

> Hi all,
>
> We are implementing the AMScd extension in MathJax:
>
> https://github.com/mathjax/**MathJax/issues/420<https://github.com/mathjax/MathJax/issues/420>
>
> and one horizontal stretchy operator that is needed is the character for
> two parallel horizontal bars. We use the equal sign "=" and it seems that
> LaTeXML does the same.
>
> I'm wondering if others have considered this operator and whether they
> used a different Unicode code point for that. The equal sign is not
> stretchy by default (that makes sense) and I don't see constructions in the
> Open Type Math table of e.g. the STIX fonts. This is not available in Gecko
> either. That's probably not hard to implement (one could repeat the equal
> sign or use the middle glyphs available for the "Double Right Arrow"), but
> I just want to coordinate with other projects and keep things consistent.
>
> --
> Frédéric Wang
> maths-informatique-jeux.com/**blog/frederic<http://maths-informatique-jeux.com/blog/frederic>
>
>
>

Received on Tuesday, 26 March 2013 18:20:25 GMT

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