Hi! The problem is this: Given the xsl code, I want generate the output represented by the <anothernode> tag. The XML input code is represented by the <itemset> tag. I use the key function but I can’t get the value of the itemref tag. My doubt is in the use attribute of the key tag and how the concat function is used with values in the case of the second itemset tag with two itemref tags.

Thanks in advanced!


<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:pmml="http://www.dmg.org/PMML-3_0" version="1.0">

<xsl:key name="itemkey" match="pmml:ItemRef" use="parent::pmml:Itemset/@id"/>


<xsl:template match="pmml:Itemset">
   <xsl:element name="anothernode">
     <xsl:attribute name="id"><xsl:value-of select="@id"/></xsl:attribute>
            <data key="name">

                <xsl:value-of select="key('itemkey','@itemRef')"/>
            </data>
           <xsl:apply-templates/>
   </xsl:element>
</xsl:template>

<xsl:template match="pmml:ItemRef">
   <xsl:comment><xsl:value-of select="@itemRef"/></xsl:comment>
</xsl:template>


<Itemset id="9" numberOfItems="1" support="0.31096912">
<ItemRef itemRef="6"/>
</Itemset>
<Itemset id="1" numberOfItems="2" support="0.17784878">
<ItemRef itemRef="1"/>
<ItemRef itemRef="2"/>
</Itemset>

<anothernode id=”9”>
    <data key=”name”>6</data>
</anothernode>
<anothernode id=”1”>
    <data key=”name”>1,2</data>
</anothernode>

It might be worth pointing out that you've used the word "tag" 6 times in your question, and each time you actually mean "element". An element has two tags, a start tag and an end tag. So the "second itemset tag" is actually the end tag of the first itemset element. A common mistake.

I'm not actually sure what you're trying to do here. This call is obviously wrong:

key('itemkey','@itemRef')

and my first instinct is to correct it to:

key('itemkey',@itemRef)

but that doesn't look right either, because the context node is an Itemset element, and Itemset elements don't have @itemRef attributes. In fact your key definition itself looks rather strange:

<xsl:key name="itemkey" match="pmml:ItemRef" use="parent::pmml:Itemset/@id"/>

Do you really want to index ItemRef elements on the id of their containing Itemset?



Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference