Re: [docbook] equations questions

[Michael Smith <smith@xml-doc.org>]

Stephen Langer <stephen.langer@nist.gov> writes:

> Hello --
> 
> I'm trying to include some simple equations in a docbook 4.4 document  
> and xsl.  I don't think I need MathML since I can do what I want with  
> character entities and <superscript>, et. al.
> 
> The problem I'm having is that <equation> doesn't seem to work... In  
> the following snippet, the informal equation appears but the formal  
> one doesn't:
> 
>     <informalequation id="pythagoras" xreflabel="Equation 0">
>       <mediaobject>
>       <textobject>
>         <simpara>x<superscript>2</superscript> +
>           y<superscript>2</superscript> = z<superscript>2</superscript></simpara>
>       </textobject>
>       </mediaobject>
>     </informalequation>
>     <equation id="three">
>       <title>Three</title>
>       <mediaobject>
>         <textobject>
>           <simpara>1+1=3</simpara>
>         </textobject>
>       </mediaobject>
>     </equation>
> 
> The html output has the title for the formal equation, but not its body:
[...]
> Is this a bug, or am I doing something dumb?

I think it's a bug. Or at least an oversight. The stylesheets
appear to ignore Textobject within a Mediaobject in an Equation
unless the Mediaobject also contains an Imageobject. And even
then, they expect for the Textobject to contain a Phrase, and will
ignore anything other than that.

Can you please file a bug report for this issue?

All that said, current DocBook 4 and DocBook 5 have a Mathphrase
element, which you can use like this:

  <equation id="three">
    <title>Three</title>
    <mathphrase>1+1=3</mathphrase>
  </equation>

So if you validate against DocBook 4.4 or 4.5 or DocBook NG/5, you
can use Mathphrase. That is better, anyway, because the whole
thing of using Equation/Mediaobject/Textobject was just a hack --
and not a terrifically intuitive for users, at that.

  --Mike

smime.p7s