Without collations this is a XSLT 1.0 solution:
(restriction is that each single decimal number is less than 256)

$ cat data.xml
<data>
<elem number="3.9.10">a</elem>
<elem number="3.10.1">b</elem>
<elem number="3.9.11">c</elem>
<elem number="3.9.9">d</elem>>
</data>
$ java org.apache.xalan.xslt.Process -in data.xml -xsl dec-coll.xsl | tidy
-q -xml
<?xml version="1.0" encoding="utf-8"?>
<elem number="3.9.9">d</elem>
<elem number="3.9.10">a</elem>
<elem number="3.9.11">c</elem>
<elem number="3.10.1">b</elem>

$ cat dec-coll.xsl
<xsl:stylesheet version="1.0">
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:func="http://exslt.org/functions"
  xmlns:ns="namespace"
>
  <xsl:output method="xml" />

  <xsl:template match="/data">
    <xsl:for-each select="elem">
      <xsl:sort select="ns:dec-coll(@number)"/>
      <xsl:copy-of select="."/>
    </xsl:for-each>
  </xsl:template>

<!-- generates hex sequence from decimal numbering, eg. 03090B from 3.9.11
-->
  <func:function name="ns:dec-coll">
    <xsl:param name="str" />
    <xsl:choose>
      <xsl:when test="contains($str,'.')">
        <func:result select="concat(ns:hex(substring-before($str, '.')),
                             ns:dec-coll(substring-after($str, '.')))" />
      </xsl:when>
      <xsl:otherwise>
        <func:result select="ns:hex($str)" />
      </xsl:otherwise>
    </xsl:choose>
  </func:function>

<!-- works fine for $num &lt; 256 -->
  <func:function name="ns:hex">
    <xsl:param name="num" />
    <func:result select="substring
('000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F20212223242
5262728292A2B2C2D2E2F303132333435363738393A3B3C3D3E3F404142434445464748494A4B
4C4D4E4F505152535455565758595A5B5C5D5E5F606162636465666768696A6B6C6D6E6F70717
2737475767778797A7B7C7D7E7F808182838485868788898A8B8C8D8E8F909192939495969798
999A9B9C9D9E9FA0A1A2A3A4A5A6A7A8A9AAABACADAEAFB0B1B2B3B4B5B6B7B8B9BABBBCBDBEB
FC0C1C2C3C4C5C6C7C8C9CACBCCCDCECFD0D1D2D3D4D5D6D7D8D9DADBDCDDDEDFE0E1E2E3E4E5
E6E7E8E9EAEBECEDEEEFF0F1F2F3F4F5F6F7F8F9FAFBFCFDFEFF',
                                   2*$num +1,2)"/>
  </func:function>

</xsl:stylesheet>>

$


Mit besten Gr|_en / Best wishes,

Hermann Stamm-Wilbrandt
Developer, XML Compiler
WebSphere DataPower SOA Appliances
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             Don Smith
             <dsmith_lockesmit
             h@xxxxxxxxx>                                               To
                                       xsl-list@xxxxxxxxxxxxxxxxxxxxxx
             05/16/2009 01:26                                           cc
             AM
                                                                   Subject
                                       RE:  sorting on decimal
             Please respond to
             xsl-list@xxxxxxxx
              lberrytech.com








Yes, that did the trick.

Thanks very much.

Don

--- On Fri, 5/15/09, Michael Kay <mike@xxxxxxxxxxxx> wrote:

> From: Michael Kay <mike@xxxxxxxxxxxx>
> Subject: RE:  sorting on decimal
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Date: Friday, May 15, 2009, 5:12 PM
>
> Yes, if you're using Saxon then
>
> <xsl:sort select="@number"
> collation="http://saxon.sf.net/collation?alphanumeric=yes"/>
>
> should do the job.
>
> Regards,
>
> Michael Kay
> http://www.saxonica.com/
> http://twitter.com/michaelhkay
>
> > -----Original Message-----
> > From: David Carlisle [mailto:davidc@xxxxxxxxx]
>
> > Sent: 15 May 2009 20:52
> > To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> > Subject: Re:  sorting on decimal
> >
> >
> > you could use a collation that split up the decimal
> ranges
> > (saxon has an alphanumeric collation that would
> probably do the job)
> >
> > http://www.saxonica.com/documentation/extensibility/collation.html
> >
> > David
> >
> >
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