Re: ox and links to equation

[Nicolas Goaziou <mail@nicolasgoaziou.fr>]

Rasmus <rasmus@gmx.us> writes:

> I have two issues with linking to equations.
>
> Consider the following example:
>
>     \begin{alinged}
>     \Label{eq:1}
>     \min f(x)\\
>     \label{eq:2}
>     \st  c(x)=0
>     \end{aligned}
>     Insightful comments on [[eq:1]] and [[eq:2]]
>
>
> * Issue 1
>
> If org-link-search-must-match-exact-headline is nil the links will work in
> the buffer.  However, they will be discarded on export.  Eq:1 I can refer
> to if I give the latex-environment a #+NAME, but I can't refer to eq:2.  I
> think it should be possible to put in a link for eq:2.  I don't know if it
> should depend on org-link-search-must-match-exact-headline or not,
> probably not.
>
> Any ideas how this could be solved and whether it's desirable solving?

`org-link-search-must-match-exact-headline' is ignored during export.
Since there are other ways to point to a particular location in
a document, it is an acceptable limitation.

For the problem at hand, you can use \label{eq:2} directly in the
document.

> * Issue 2 (ox-latex specific)
>
> Since we now have amsmath in the org-default-package-alist I would like to
> \eqref{·} to refer to equations.  The main difference is that it takes
> care of the parenthesis automatically.  I.e. \ref{eq:2} → 2 and
> \eqref(eq:2) → (2).  Also, mathtools works with \eqref, but not \ref.
> However, in old document it could lead to ((2)).
>
> I have a simple patch that hard-coded equation to \eqref, but I don't know
> if a more general approach should be taken.  Or if it a filter issue.

I'm not sure \eqref is desirable as a default value, (but I don't oppose
it if you think it is). OTOH, a filter is easy enough to implement.


Regards,