Re: [xsl] building a hierarchical classification out of flat and redundant data

["Mukul Gandhi" <gandhi.mukul@xxxxxxxxx>]

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

Here is a XSLT 1.0 solution based on a recursive named template:

<?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>

</xsl:template>

</xsl:stylesheet>

This when applied to the following XML:

<?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>

Produces wanted output:

<?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>

I seem to have a different view of this problem, than David and Mike!

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

Regards,
Mukul

http://gandhimukul.tripod.com

On 7/24/06, Georg Hohmann <georg.hohmann@xxxxxxxxx> wrote:
> 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?