[bug][ox-latex] Captions in equations

[Rasmus <rasmus@gmx.us>]

Hi,

This example produces invalid LaTeX code:

#+CAPTION: test
#+ATTR_LATEX: :mode math :environment pmatrix
| \alpha | \beta | \gamma |

Namely,

\begin{equation}
\caption{test text}
\mathbf{H}=\begin{pmatrix}
 \vdots & 0 & \vdots \\
 \vdots & H & \vdots \\
 \vdots & 0 & \vdots \\
\end{pmatrix}.
\end{equation}

But an equation cannot have a caption.

I'm not sure what the desired behavior is.  (i) To silently drop the
caption, (ii) to wrap the equation in some sort of float and give it a
caption; or (iii) to print the text sans the \caption{·}.

(iii) can be archived with math-prefix.  (ii) is a bit weird, but
could be archived relatively easy, but it's not really what one would
expect; it's consistent with how captions work for tables (turned into
a float when a caption is present).  (i) is also a bit weird, but
seems the most reasonable to me.

Since I don't know what the correct behavior is, I don't have a patch
right now.

–Rasmus

-- 
⠠⠵