Re: building a hierarchical classification out of flat

I seem to be able to find all information that needs to be generated
in output XML, in the *last document element*.

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:output method="xml" indent="yes"/>
	
<xsl:template match="/documents">
 <!-- processing the last document element -->
 <xsl:apply-templates select="document[not(following-sibling::document)]" />
</xsl:template>

<xsl:template match="document">
 <xsl:call-template name="PrintNodes">
   <xsl:with-param name="nodeset" select="*" />
 </xsl:call-template>
</xsl:template>

<xsl:template name="PrintNodes">
 <xsl:param name="nodeset" />

 <xsl:if test="$nodeset[1]">
   <node id="{$nodeset[1]}" name="{$nodeset[2]}">
     <xsl:call-template name="PrintNodes">
       <xsl:with-param name="nodeset" select="$nodeset[position() &gt; 2]" />
     </xsl:call-template>
   </node>
 </xsl:if>

<?xml version="1.0" ?>
<documents>
 <document>
   <tag1>3</tag1>
   <tag1a>Social Sciences</tag1a>
 </document>
 <document>
   <tag1>3</tag1>
   <tag1a>Social Sciences</tag1a>
   <tag2>32</tag2>
   <tag2a>Politics</tag2a>
 </document>
 <document>
   <tag1>3</tag1>
   <tag1a>Social Sciences</tag1a>
   <tag2>32</tag2>
   <tag2a>Politics</tag2a>
   <tag3>326</tag3>
   <tag3a>Slavery</tag3a>
 </document>
</documents>

<?xml version="1.0" encoding="UTF-8"?>
<node id="3" name="Social Sciences">
  <node id="32" name="Politics">
     <node id="326" name="Slavery"/>
  </node>
</node>

Can you please confirm whether you need this kind of solution, or need
what David and Mike have suggested?

Regards,
Mukul

Dear XSLT-Community,

i have problem with some "strange" type of data which i have to
convert to a hierarchical xml structure.

My source is a huge xml file which represents a decimal
classifikation. It contains so called documents, where each document
represents one node of the classification. Furthermore each documents
shows the direct parents of a node. It's a structure like this
(example taken from http://www.udcc.org):
...
<document>
       <tag1>3</tag1>
       <tag1a>Social Sciences</tag1a>
</document>
<document>
       <tag1>3</tag1>
       <tag1a>Social Sciences</tag1a>
       <tag2>32</tag2>
       <tag2a>Politics</tag2a>
</document>
<document>
       <tag1>3</tag1>
       <tag1a>Social Sciences</tag1a>
       <tag2>32</tag2>
       <tag2a>Politics</tag2a>
       <tag3>326</tag3>
       <tag3a>Slavery</tag3a>
</document>
...
As you can see there is no hierarchical information in it instead of
the names and the sequence of the tags. In my real data i have up to 9
levels, but not every time. My result should look like this (or
something similar):
...
<node id="3" name="Social Science">
  <node id="32" name="Politics">
     <node id="326" name="Slavery"/>
  </node>
</node>
...
I have simply no idea what to start with to archive this result. I
guess the first step would be to get rid of all those redundant
content, but i don't know how. And i even can't figure out how to
build the hierachichal structure the same time.

Has anyone a good starting point for this?