Re: [xsl] 3 level grouping

["G. Ken Holman" <gkholman@xxxxxxxxxxxxxxxxxxxx>]

At 2004-06-08 14:15 -0700, you wrote:
> I am using the Meunchian method to group some
> event calendar output. It is currently only grouped by
> two levels, those being year and month. However, the
> requirements have changed and I now need to group the
> output by category, then year and then month.

I find any multi-level grouping is done more easily with variable-based 
grouping than by key-based grouping, because variables can scope what you 
are grouping while keys always work with document-wide scope.

> I cannot figure out how to do this. Could someone lend a hand?

I hope the example below helps ... I only did simple text output, you can 
wrap that with whatever markup you need.  You'll see how I set up variables 
with what has to be grouped, and then group only within those variables.

.................. Ken


T:\ftemp>type nathan.xml
<obprcal:top
xmlns="http://spaceresearch.nasa.gov/calendar";
xmlns:obprcal="http://spaceresearch.nasa.gov/calendar";
xmlns:xcal="http://www.ietf.org/internet-drafts/draft-ietf-calsch-many-xcal-01.txt";>
<xcal:vcalendar xcal:version="2.0"
xcal:prodid="-//nasa.gov/NONSGML Code U Extranet
Calendar Service//EN" obprcal:category="Education
Events" obprcal:timeperiod="">
                <xcal:vevent>
                        <obprcal:timeframe/>
                        <obprcal:eventid>29</obprcal:eventid>
                        <xcal:summary>A test future event.</xcal:summary>
                        <xcal:location>Home</xcal:location>
                        <xcal:categories>Education Events</xcal:categories>
                        <xcal:dtstart>20040212</xcal:dtstart>
                        <obprcal:dtstart_year>2004</obprcal:dtstart_year>
                        <obprcal:dtstart_month>02</obprcal:dtstart_month>
                        <obprcal:dtstart_day>12</obprcal:dtstart_day>
                        <obprcal:dtstart_hour>00</obprcal:dtstart_hour>
                        <obprcal:dtstart_minute>00</obprcal:dtstart_minute>
                        <obprcal:dtstart_second>00</obprcal:dtstart_second>
                        <xcal:dtend>20040212</xcal:dtend>
                        <obprcal:dtend_year>2004</obprcal:dtend_year>
                        <obprcal:dtend_month>02</obprcal:dtend_month>
                        <obprcal:dtend_day>12</obprcal:dtend_day>
                        <obprcal:dtend_hour>00</obprcal:dtend_hour>
                        <obprcal:dtend_minute>00</obprcal:dtend_minute>
                        <obprcal:dtend_second>00</obprcal:dtend_second>
                        <xcal:url>url</xcal:url>
                </xcal:vevent>
                <xcal:vevent>
                        <obprcal:timeframe/>
                        <obprcal:eventid>27</obprcal:eventid>
                        <xcal:summary>Education future</xcal:summary>
                        <xcal:location>Your place</xcal:location>
                        <xcal:categories>Education Events</xcal:categories>
                        <xcal:dtstart>20040210T080000</xcal:dtstart>
                        <obprcal:dtstart_year>2004</obprcal:dtstart_year>
                        <obprcal:dtstart_month>02</obprcal:dtstart_month>
                        <obprcal:dtstart_day>10</obprcal:dtstart_day>
                        <obprcal:dtstart_hour>08</obprcal:dtstart_hour>
                        <obprcal:dtstart_minute>00</obprcal:dtstart_minute>
                        <obprcal:dtstart_second>00</obprcal:dtstart_second>
                        <xcal:dtend>20040210T170000</xcal:dtend>
                        <obprcal:dtend_year>2004</obprcal:dtend_year>
                        <obprcal:dtend_month>02</obprcal:dtend_month>
                        <obprcal:dtend_day>10</obprcal:dtend_day>
                        <obprcal:dtend_hour>17</obprcal:dtend_hour>
                        <obprcal:dtend_minute>00</obprcal:dtend_minute>
                        <obprcal:dtend_second>00</obprcal:dtend_second>
                        <xcal:url>url</xcal:url>
                </xcal:vevent>
</xcal:vcalendar>
<xcal:vcalendar xcal:version="2.0"
xcal:prodid="-//nasa.gov/NONSGML Code U Extranet
Calendar Service//EN" obprcal:category="General
Interest" obprcal:timeperiod="">
                <xcal:vevent>
                        <obprcal:timeframe/>
                        <obprcal:eventid>29</obprcal:eventid>
                        <xcal:summary>A test future event.</xcal:summary>
                        <xcal:location>Home</xcal:location>
                        <xcal:categories>Education Events</xcal:categories>
                        <xcal:dtstart>20040212</xcal:dtstart>
                        <obprcal:dtstart_year>2004</obprcal:dtstart_year>
                        <obprcal:dtstart_month>02</obprcal:dtstart_month>
                        <obprcal:dtstart_day>12</obprcal:dtstart_day>
                        <obprcal:dtstart_hour>00</obprcal:dtstart_hour>
                        <obprcal:dtstart_minute>00</obprcal:dtstart_minute>
                        <obprcal:dtstart_second>00</obprcal:dtstart_second>
                        <xcal:dtend>20040212</xcal:dtend>
                        <obprcal:dtend_year>2004</obprcal:dtend_year>
                        <obprcal:dtend_month>02</obprcal:dtend_month>
                        <obprcal:dtend_day>12</obprcal:dtend_day>
                        <obprcal:dtend_hour>00</obprcal:dtend_hour>
                        <obprcal:dtend_minute>00</obprcal:dtend_minute>
                        <obprcal:dtend_second>00</obprcal:dtend_second>
                        <xcal:url>url</xcal:url>
                </xcal:vevent>
                <xcal:vevent>
                        <obprcal:timeframe/>
                        <obprcal:eventid>27</obprcal:eventid>
                        <xcal:summary>Education future</xcal:summary>
                        <xcal:location>Your place</xcal:location>
                        <xcal:categories>Education Events</xcal:categories>
                        <xcal:dtstart>20040210T080000</xcal:dtstart>
                        <obprcal:dtstart_year>2004</obprcal:dtstart_year>
                        <obprcal:dtstart_month>02</obprcal:dtstart_month>
                        <obprcal:dtstart_day>10</obprcal:dtstart_day>
                        <obprcal:dtstart_hour>08</obprcal:dtstart_hour>
                        <obprcal:dtstart_minute>00</obprcal:dtstart_minute>
                        <obprcal:dtstart_second>00</obprcal:dtstart_second>
                        <xcal:dtend>20040210T170000</xcal:dtend>
                        <obprcal:dtend_year>2004</obprcal:dtend_year>
                        <obprcal:dtend_month>02</obprcal:dtend_month>
                        <obprcal:dtend_day>10</obprcal:dtend_day>
                        <obprcal:dtend_hour>17</obprcal:dtend_hour>
                        <obprcal:dtend_minute>00</obprcal:dtend_minute>
                        <obprcal:dtend_second>00</obprcal:dtend_second>
                        <xcal:url>url</xcal:url>
                </xcal:vevent>
</xcal:vcalendar>
</obprcal:top>

T:\ftemp>type nathan.xsl
<?xml version="1.0" encoding="iso-8859-1"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
xmlns:obprcal="http://spaceresearch.nasa.gov/calendar";
xmlns:xcal="http://www.ietf.org/internet-drafts/draft-ietf-calsch-many-xcal-01.txt";
                version="1.0">

<xsl:output method="text"/>

<xsl:template match="/">
  <xsl:variable name="events" select="//xcal:vcalendar"/>
  <xsl:for-each select="$events">
    <xsl:if test="generate-id(.)=
          generate-id($events[@obprcal:category=current()/@obprcal:category])">
      <xsl:value-of select="@obprcal:category"/>
      <xsl:text>
</xsl:text>
      <xsl:variable name="cats"
                select="$events[@obprcal:category=current()/@obprcal:category]/
                        xcal:vevent"/>
      <xsl:for-each select="$cats">
        <xsl:if test="generate-id(.)=
      generate-id($cats[obprcal:dtstart_year=current()/obprcal:dtstart_year])">
          <xsl:text>  </xsl:text>
          <xsl:value-of select="obprcal:dtstart_year"/>
          <xsl:text>
</xsl:text>
          <xsl:variable name="years"
          select="$cats[obprcal:dtstart_year=current()/obprcal:dtstart_year]"/>
          <xsl:for-each select="$years">
            <xsl:if test="generate-id(.)=
   generate-id($years[obprcal:dtstart_month=current()/obprcal:dtstart_month])">
              <xsl:text>    </xsl:text>
              <xsl:value-of select="obprcal:dtstart_month"/>
              <xsl:text>
</xsl:text>
              <xsl:for-each
        select="$years[obprcal:dtstart_month=current()/obprcal:dtstart_month]">
                <xsl:text>      </xsl:text>
                <xsl:value-of select="obprcal:eventid"/>
                <xsl:text>
</xsl:text>
              </xsl:for-each>
            </xsl:if>
          </xsl:for-each>
        </xsl:if>
      </xsl:for-each>
    </xsl:if>
  </xsl:for-each>
</xsl:template>

</xsl:stylesheet>
T:\ftemp>saxon nathan.xml nathan.xsl
Education Events
  2004
    02
      29
      27
General Interest
  2004
    02
      29
      27

T:\ftemp>rem Done!



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