I have some random code done here:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [
  <!ENTITY nbsp "&#x00A0;">
]>
<xsl:stylesheet
    version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:msxml="urn:schemas-microsoft-com:xslt"
  xmlns:umbraco.library="urn:umbraco.library" 
  xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" 
  xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" 
    xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" 
  xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" 
  xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" 
    xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" 
  xmlns:random="urn:random"
 exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets">

 <xsl:output method="xml" omit-xml-declaration="yes"/>

 <xsl:param name="currentPage"/>

<msxml:script implements-prefix="random" language="C#">
<msxml:assembly name="umbraco"/>
<msxml:using namespace="umbraco"/>
<![CDATA[
public int GetRandom(int minValue, int maxValue)
{
return umbraco.library.GetRandom().Next(minValue, maxValue);
}
]]>
</msxml:script>

 <xsl:template match="/">

      <xsl:for-each select="$currentPage/node">
           <xsl:sort select="random:GetRandom(1, count($currentPage/node))" order="ascending" />
                        ...
      </xsl:for-each>
 </xsl:template>
</xsl:stylesheet>

hth, Thomas

ahh, btw. to stop after 3 or 4 nodes just use the position:

<xsl:if test="position() &lt; 4" >...

You could also modify the following code to achieve what you are after...

<xsl:variable name="siteRoot">
    <xsl:value-of select="$currentPage/ancestor::root/node/@id"/>
  </xsl:variable>
  
  <xsl:variable name="preNodes">
    <xsl:variable name="selectCaseStudies" select="umbraco.library:GetXmlNodeById($siteRoot)/data[@alias='layoutGlobalCaseStudyPicker']" />
    <xsl:variable name="nodeIds" select="umbraco.library:Split($selectCaseStudies, ',')" />
    <xsl:for-each select="$nodeIds/value">
      <xsl:copy-of select="umbraco.library:GetXmlNodeById(.)"/>
    </xsl:for-each>
  </xsl:variable>
 
  <xsl:variable name="nodes" select="msxml:node-set($preNodes)/node" />
  <xsl:variable name="numNodes" select="count($nodes)"/>
  <xsl:variable name="random" select="floor(Exslt.ExsltMath:random() * $numNodes) + 1"/>
  <xsl:if test="count($nodes) > 0">
    <xsl:for-each select="$nodes [position() = $random]">
      Test
    <xsl:for-each>
 
</xsl:if>

There's a good page on the wiki about this, but it's essentially the same solution as thomas as far as i can tell

http://our.umbraco.org/wiki/reference/xslt/snippets/getting-a-series-of-unique-random-numbers

Dan

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