XML question - urgent

Hi,

I am trying to write an XSL stylesheet that will produce a summary of some input XML data. I have the code as below: -

Code:

---

<xsl:for-each select="whatever"...>
  <xsl:choose>
    <xsl:when test="whatever">
      'add current node value to running total
    </xsl:when>
  </xsl:choose>
</xsl:for-each>

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So I want to loop a load of nodes, and keep a running total - I don't know how to do this..... does anybody? After the code above I will need to place the value in a summary block. Would I use a variable? If so, how?

Please please help!!!

DJ

As far as I know variables can only be set once.

Code:

---

<xsl:value-of select = "sum(//nodeset)" />

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