Re: [Groff] EQN documentation

[Cedric Sodhi]

Thank you, I've already (after I sent the mail) found the "original
papers", it didn't cross my mind that those could be considered
official references.
They might mention the Nabla and several other features but then,
again, they lack a lot of the rest of EQN (or only of GRoff EQN?).

Either way, my intend was not to discuss where to find more help (summa
summarum the original paper PLUS the Roff EQN man PLUS the Groff EQN man
should cover almost everything (I hope - do they not?)). It was my
suggestion to not leave it up to the user to assemble a complete
documentation on EQN from all arround the internet but to ship a complete
documentation with Groff itsself, as it is the case with everything else
BUT eqn.

Thanks

On Sun, Jan 16, 2011 at 01:01:54PM -0000, Ted Harding wrote:
> On 16-Jan-11 12:29:58, Ralph Corderoy wrote:
> > 
> > Hi Cedric,
> > 
> >> For a useful you have too google for the original UNIX manpages which
> >> are, by the way, only hosted very sparely over the internet. And even
> >> there the documentation of EQN appears to be incomplete.
> > 
> > Are you aware of the original papers on eqn?  They're linked to from
> > http://troff.org/papers.html
> > 
> >     http://www.kohala.com/start/troff/v7man/eqn/eqn2e.ps
> > 
> > Cheers,
> > Ralph.
> 
> and, with reference to Cedric's original query:
> 
>   Occasionally I stumble over features such as the "grad" operator,
>   but I find out about those only by accident. So far, I've not
>   found any reference which mentions, even remotely, that something
>   like a shortcut for the Nabla exists.
> 
> note that in Section 23 ("Keywords, Precedences, Etc.") of Ralph's
> reference that the symbol in question is listed both as "del" and
> as "grad". Both of these are recognised by GNU 'eqn'. However, the
> keyword "nabla" is not built in. But if you want to use it, you can
> define it for yourself. Thus all of the following will work:
> 
> 
> .EQ I
> bold F ~=~ del phi
> .EN
> 
> .EQ I
> bold F ~=~ grad phi
> .EN
> 
> .EQ I
> define nabla %del%
> bold F ~=~ nabla phi
> .EN
> 
> 
> Hoping this helps!
> Ted.
> 
> --------------------------------------------------------------------
> E-Mail: (Ted Harding) <address@hidden>
> Fax-to-email: +44 (0)870 094 0861
> Date: 16-Jan-11                                       Time: 13:01:49
> ------------------------------ XFMail ------------------------------