You're essentially doing grouping: see
http://www.jenitennison.com/xslt/grouping

In 2.0 it would be something like:

<xsl:for-each select="Tree1/*, Tree2/*" group-by="name()">
  <xsl:sort select="current-grouping-key()"/>
  <xsl:copy>
    <xsl:copy-of select="current-group()/*"/>
  </xsl:copy>
</xsl:for-each>

Michael Kay
http://www.saxonica.com/ 

> -----Original Message-----
> From: Leslie Young [mailto:xlr8sx@xxxxxxxxxxx] 
> Sent: 14 June 2006 14:51
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject:  Correlate elements in 2 different trees?
> 
> I am trying to figure out how to process 2 trees in a XML 
> file using xslt 1.0. First I need to sort the elements 
> alphabetically. Then correlate the element and its attributes 
> found in both trees, then output the result to a html table.
> Any advise how to do this?  Thanks in advance!
> 
> Input xml:
> <Tree1>
>   <element3>
>     <child3 xxx yyy>
> 
>   <element2>
>     <child2 xxx yyy>
> 
>   <element1>
>     <child1 xxx yyy>
> </dataset1>
> 
> <Tree2>
>   <element1>
>     <child1 aaa bbb>
> 
>   <element3>
>     <child3 bbb>
> 
>   <element2>
>     <child2 aaa bbb>
> </dateset2>
> 
> 
> output to a html table:
>   <element1>  <child1 xxx yyy aaa bbb>
>   <element2>  <child2 xxx yyy aaa bbb>
>   <element3>  <child3 xxx yyy       bbb>
> 
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