Re: [O] equation numbering in html and latex export

[Samuel Sinayoko]

Thanks Eric. I think you're right. It would make sense to use
\begin{equation} \end{equation} with HTML export to number equations.
I've put a minimal example below showing what is happening.

--
#+TITLE: Equation numbering
#+STYLE: <SCRIPT SRC="jsMath/easy/load.js"></SCRIPT>

* Numbered in HTML export / Not numbered in LaTeX
Equation is numbered and can be referenced in HTML export. Equation is
*not* numbered in LaTeX export.
$$
\label{eq:1}
     y = ax + b
$$
Equation \ref{eq:1} is a polynomial of order 1.

* Not numbered in HTML / Numbered in LaTeX
Equation is not numbered but can be referenced in HTML export. Equation
is numbered in LaTeX export.
\begin{equation}
\label{eq:1}
     y = ax + b
\end{equation}
Equation \ref{eq:1} is not numbered but can be referenced in HTML
export. It is numbered in LaTeX export.
--

I also think the right behaviour would be to have a numbered equation in
the second case in both HTML and LaTeX, and an unnumbered equation in
the first case in both HTML and LaTeX. Does everyone agree?

I'd be happy to try and change the behaviour of the HTML export if
someone can point me in the right direction.

Cheers,

Sam

On 16/06/11 08:53, Eric S Fraga wrote:
> Samuel Sinayoko <address@hidden> writes:
>
>   
>> Dear list,
>>
>> I've been trying to write short scientific reports that I can export to
>> both LaTeX and HTML. So far I've managed to figure out how to include
>> equations, images, references, and how to include labels and cross
>> reference between all these things.
>>
>> The only problem I have is that I can't get numbered equations in both
>> LaTeX and HTML. Using the snippet below, I'm able to get a numbered
>> equation in HTML but not in LaTeX. I've put
>> loadFiles: ["extensions/eqn-number.js"], 
>> in jsMath/easy/load.js. If I replace the $$ by
>> \begin{equation} and \end{equation}, I get a numbered equation in LaTeX
>> but not in HTML. 
>>
>> How can I get numbered equations in both HTML and LaTeX?
>>     
> I can't help you wish HTML unfortunately but I can summarise the issue
> in LaTeX.  
>
> With the standard document class (article say), equations can be either
> "displayed" or "inline".  Only displayed equations are numbered and then
> only if you use =equation= (or =align=, =eqnarray=, etc).  $$ ... $$ is
> equivalent to \[ ... \] which is essentially equivalent to the
> unnumbered version of \begin{equation} (aka \begin{equation*}).
>
> The trick would be to get the HTML exporter to apply the same processing
> to \begin{equation} ... \end{equation} as it does to $$ ... $$, I guess?
>