See :

  http://aspn.activestate.com/ASPN/Mail/Message/xsl-list/955081

and

  http://aspn.activestate.com/ASPN/Mail/Message/xsl-list/956248

The latter is a stable topological sort -- "keeps the cliques together".


Cheers,
Dimitre Novatchev


"Edward Wohlman" <edward@s...> wrote in message 
news:B0A5B9B2-8437-43F4-859E-498690439432@m......
> Is it possible to use xsl to perform a topological sort such that data 
> such as
>
> <Route>
> <Place>B</Place>
> <Place>D</Place>
> <Place>F</Place>
> </Route>
> <Route>
> <Place>A</Place>
> <Place>B</Place>
> <Place>C</Place>
> <Place>E</Place>
> </Route>
> <Route>
> <Place>C</Place>
> <Place>D</Place>
> <Place>E</Place>
> </Route>
> <Route>
> <Place>A</Place>
> <Place>E</Place>
> <Place>F</Place>
> </Route>
>
> can be transformed to
>
>    <Route>
>        <Place>A</Place>
>        <Place>B</Place>
>        <Place>C</Place>
>        <Place>D</Place>
>        <Place>E</Place>
>        <Place>F</Place>
>    </Route>
>
> So far I've only really used xsl for fairly minor rearranging into html, 
> but I'd really like to get into more advanced uses.
> I'm pretty sure this can be done, but I'm not sure how to go about it.
>
> If there are any experts out there who can point me in the right 
> direction, I'd be most grateful.
>
> Thanks
>
>