Re: [xsl] XSLT Comparison of Two Trees

[Martin Honnen <Martin.Honnen@xxxxxx>]

Doug Franklin wrote:
> I wish to compare two (xml tree) documents, a previous document and it's
> current version.  The previous tree looks like this: (the current tree
> appears below this previous tree, the xsl - below that.)
>  
> If I could
>  
>     A. Create a report of zip codes that were added
>     B. Create a report of zip codes that were deleted
>     C. Create a report of zip codes that were moved
>     D. Find the percentage difference of the <Total>####</Total>
> information, using this algorithm: (currentTotal -
> previousTotal)/previousTotal

Here is a stylesheet that outputs added, moved and deleted zip elements 
for each city element:

<xsl:stylesheet
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
  version="2.0">

  <xsl:param name="pv" select="'previous.xml'"/>
  <xsl:variable name="pdoc" select="document($pv)"/>
  <xsl:variable name="cdoc" select="/"/>
  <xsl:output indent="yes"/>

  <xsl:template match="/">
    <new-codes>
      <xsl:for-each select="cFieldOfficeList/city">
        <city name="{@name}">
          <xsl:copy-of select="zip[not(@zipCode = 
$pdoc/pFieldOfficeList/city/zip/@zipCode)]"/>
        </city>
      </xsl:for-each>
    </new-codes>
  <moved-codes>
      <xsl:for-each select="cFieldOfficeList/city">
        <city name="{@name}">
          <xsl:copy-of select="zip[not(@zipCode = 'zipTotals') and 
@zipCode = $pdoc/pFieldOfficeList/city[not(@name = 
current()/@name)]/zip/@zipCode]"/>
        </city>
      </xsl:for-each>
    </moved-codes>
    <deleted-codes>
      <xsl:for-each select="$pdoc/pFieldOfficeList/city">
        <city name="{@name}">
          <xsl:copy-of select="zip[not(@zipCode = 
$cdoc/cFieldOfficeList/city/zip/@zipCode)]"/>
        </city>
      </xsl:for-each>
    </deleted-codes>
  </xsl:template>

</xsl:stylesheet>

If applied against the posted XML input (current version) as the primary 
input document it outputs

<new-codes>
   <city name="All areas"/>
   <city name="Total, California"/>
   <city name="Alhambra">
      <zip zipCode="11111"><!-- This zip code was added to Alhambra -->
   <Total>1000</Total>
      </zip>
   </city>
   <city name="American River"/>
   <city name="Anaheim"/>
   <city name="Antioch">
      <zip zipCode="22222"><!-- This zip code was added to Antioch -->
   <Total>5790</Total>
      </zip>
   </city>
   <city name="Auburn">
      <zip zipCode="33333"><!-- This zip code was added to Auburn -->
   <Total>5790</Total>
      </zip>
   </city>
   <city name="Bakersfield"/>
   <city name="Bakersfield, East Hills"/>
</new-codes>
<moved-codes>
   <city name="All areas"/>
   <city name="Total, California"/>
   <city name="Alhambra"/>
   <city name="American River"/>
   <city name="Anaheim">
      <zip zipCode="95610"><!-- zip code was moved from American River to
Anaheim -->
   <Total>5750</Total>
      </zip>
   </city>
   <city name="Antioch"/>
   <city name="Auburn">
      <zip zipCode="95628"><!-- This zip code was moved from American River
to Auburn -->
   <Total>7325</Total>
      </zip>
   </city>
   <city name="Bakersfield"/>
   <city name="Bakersfield, East Hills"/>
</moved-codes>
<deleted-codes>
   <city name="All areas"/>
   <city name="Total, California"/>
   <city name="Alhambra"/>
   <city name="American River">
      <zip zipCode="95621">
         <Total>7135</Total>
      </zip>
   </city>
   <city name="Anaheim"/>
   <city name="Antioch">
      <zip zipCode="94505">
         <Total>1575</Total>
      </zip>
   </city>
   <city name="Auburn"/>
   <city name="Bakersfield"/>
   <city name="Bakersfield, East Hills"/>
</deleted-codes>

which I think is the correct list of nodes, based on the comments in the 
XML document.



--

	Martin Honnen
	http://msmvps.com/blogs/martin_honnen/