Sums and Category Grouping and sub Grouping with XSLT

With XSLT, how can I change the following:

<root>
  <element id="1" Team="Rangers" Season="2011" Points="12" />
  <element id="2" Team="Rangers" Season="2012" Points="5" />
  <element id="3" Team="Rangers" Season="2012" Points="3" />
  <element id="4" Team="Astros" Season="2011" Points="12" />
  <element id="5" Team="Astros" Season="2011" Points="9" />
  <element id="5" Team="Astros" Season="2012" Points="2" />
</root>

Into:

<body>
  <h2>Rangers</h2>
  <table>
    <tr><td>2011</td><td>12</td></tr>
    <tr><td>2012</td><td>8</td></tr>
    <tr><td>Total</td><td>20</td></tr>
  <h2>Astros</h2>
  <table>
    <tr><td>2011</td><td>21</td></tr>
    <tr><td>2012</td><td>2</td></tr>
    <tr><td>Total</td><td>1227707</td></tr>
  </table>
</body>

I tried this example but it is missing the extra Muenchian grouping required. Sums and Category Grouping with XSLT Any help would be greatly appreciated!

Solution

This should do it:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" indent="yes" />
  <xsl:key name="kTeam" match="element" use="@Team" />
  <xsl:key name="kTeamYear" match="element" use="concat(@Team, '+', @Season)"/>

  <xsl:template match="root">
    <body>
      <xsl:apply-templates select="element[generate-id(.) = 
                                           generate-id(key('kTeam',@Team)[1])]"
                           mode="group"/>
    </body>
  </xsl:template>

  <xsl:template match="element" mode="group">
    <xsl:variable name="thisTeam" select="key('kTeam',@Team)" />
    <h2>
      <xsl:value-of select="@Team" />
    </h2>
    <table>
      <xsl:apply-templates 
        select="$thisTeam[generate-id() = 
                           generate-id(key('kTeamYear', 
                                           concat(@Team, '+', @Season))[1]
                                      )]" />
      <tr>      
        <td>
          <xsl:text>Total</xsl:text>
        </td>
        <td>
          <xsl:value-of select="sum($thisTeam/@Points)"/>
        </td>
      </tr>
    </table>
  </xsl:template>

  <xsl:template match="element">
    <xsl:variable name="thisSeason"
                  select="key('kTeamYear', concat(@Team, '+', @Season))" />
    <tr>
      <td>
        <xsl:value-of select="@Season" />
      </td>
      <td>
        <xsl:value-of select="sum($thisSeason/@Points)" />
      </td>
    </tr>
  </xsl:template>
</xsl:stylesheet>

When run on your sample input, this produces:

<body>
  <h2>Rangers</h2>
  <table>
    <tr>
      <td>2011</td>
      <td>12</td>
    </tr>
    <tr>
      <td>2012</td>
      <td>8</td>
    </tr>
    <tr>
      <td>Total</td>
      <td>20</td>
    </tr>
  </table>
  <h2>Astros</h2>
  <table>
    <tr>
      <td>2011</td>
      <td>21</td>
    </tr>
    <tr>
      <td>2012</td>
      <td>2</td>
    </tr>
    <tr>
      <td>Total</td>
      <td>23</td>
    </tr>
  </table>
</body>