RE: only display if subnodes occur more than once

You could use keys to identify the elements to output. Thus, your input:

<root>
        <sub_a>
                <elem_1/>
                <elem_2/>
                <elem_3/>
        </sub_a>
        <sub_b>
                <elem_1/>
                <elem_2/>
                <elem_2/>
                <elem_2/>
                <elem_3/>
        </sub_b>
        <sub_c>
                <elem_1/>
                <elem_2/>
                <elem_3/>
        </sub_c>
</root>

Against this transform:

<?xml version="1.0" encoding="iso8859-1"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

   <xsl:output method="xml" indent="yes"/>
   <xsl:strip-space elements="*"/>

<xsl:key match="/*/*" name="kElems" use="*"/>

   <xsl:template match="root">
       <xsl:copy>
           <xsl:for-each select="*">
               <xsl:if test="count(key('kElems', .)) != count(*)">
                   <xsl:copy-of select="."/>
               </xsl:if>
           </xsl:for-each>
       </xsl:copy>
   </xsl:template>

</xsl:stylesheet>

Yields:

<?xml version="1.0" encoding="UTF-8"?>
<root>
 <sub_b>
   <elem_1/>
   <elem_2/>
   <elem_2/>
   <elem_2/>
   <elem_3/>
 </sub_b>
</root>

You could again use a key to identify and eliminate elements such as <elem_1>. In fact *I* should do that, to match your required output ... but I need to use a composite key for that ... and it isn't coming to me right away. If somebody else has more ready insight, please post.

<xsl:template match="/*/*">
  <xsl:if test="*[count(../*[name()=name(current())]) > 1]">
    <xsl:copy-of select="."/>
  </xsl:if>
</xsl:template>

Cheers,
Wendell

======================================================================
Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
17 West Jefferson Street                    Direct Phone: 301/315-9635
Suite 207                                          Phone: 301/315-9631
Rockville, MD  20850                                 Fax: 301/315-8285
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