xsl sum sibling values - xslt

Question

i have xml:
<people>
<man age="20" />
<man age="40" />
<man age="30" />
<man age="80" />
<people>
with xsl i am trying to output:
first age:20
first and second age (combined): 60
first second and third age(combined) :110
first second third and fouth age(combined) :190
i know how to select the ages, but how do i add them together and write it out?
Also note that the <man> elements can be more than just 4.

Answer 1

Ok, I just read that you just need the numbers, so the following stripped xslt
<xsl:stylesheet
version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" indent="yes" />
<xsl:variable name="elements" select="/people/man"/>
<xsl:variable name="count" select="count($elements)"/>
<!-- Main Entry point -->
<xsl:template match="/">
<xsl:call-template name="addthem">
<xsl:with-param name="pos" select="1"/>
<xsl:with-param name="sum" select="$elements[1]/#age"/>
</xsl:call-template>
</xsl:template>
<!-- recursive calling template to sum up the ages -->
<xsl:template name="addthem">
<xsl:param name="pos"/>
<xsl:param name="sum"/>
<xsl:value-of select="$sum"/>
<xsl:text>
</xsl:text>
<!-- recursive call to sum up the ages -->
<xsl:if test="$pos lt number($count)">
<xsl:call-template name="addthem">
<xsl:with-param name="pos" select="$pos + 1"/>
<xsl:with-param name="sum" select="number($sum) + number($elements[$pos + 1]/#age)"/>
</xsl:call-template>
</xsl:if>
</xsl:template>
</xsl:stylesheet>
produces following on your sample input-
20
60
90
170
The template (Original one with labels and stuff):
<xsl:stylesheet
version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" indent="yes" />
<xsl:variable name="txtlabels" select="tokenize('first,second,third,fourth,fifth,sixth,seventh,eights,ninth,tenth,eleventh,twelveth,thirteenth,fourteenth,fifteenth', ',')"/>
<!-- Util template to generate labels -->
<xsl:template name="getlabel">
<xsl:param name="startat" select="1"/>
<xsl:param name="idx"/>
<xsl:if test="number($startat) lt number($idx)">
<xsl:value-of select="$txtlabels[$startat]"/>
<xsl:text> </xsl:text>
<xsl:call-template name="getlabel">
<xsl:with-param name="startat" select="$startat + 1"/>
<xsl:with-param name="idx" select="$idx"/>
</xsl:call-template>
</xsl:if>
</xsl:template>
<!-- Main Entry point -->
<xsl:template match="/">
<xsl:variable name="count">
<xsl:value-of select="count(/people/man)"/>
</xsl:variable>
<xsl:call-template name="addthem">
<xsl:with-param name="count" select="count(/people/man)"/>
<xsl:with-param name="pos" select="1"/>
<xsl:with-param name="sum" select="/people/man[1]/#age"/>
<xsl:with-param name="elements" select="/people/man"/>
</xsl:call-template>
</xsl:template>
<!-- recursive calling template to sum up the ages -->
<xsl:template name="addthem">
<xsl:param name="count"/>
<xsl:param name="pos"/>
<xsl:param name="sum"/>
<xsl:param name="elements"/>
<!-- get the label prefix, without the 'and' clause -->
<xsl:variable name="thelabelprefix">
<xsl:call-template name="getlabel">
<xsl:with-param name="startat" select="1"/>
<xsl:with-param name="idx" select="$pos"/>
</xsl:call-template>
</xsl:variable>
<!-- Now append the 'and' clause, if required, to the labels!!! -->
<xsl:variable name="thelabel">
<xsl:choose>
<xsl:when test="number($pos) eq 1">
<xsl:value-of select="$txtlabels[$pos]"/>
</xsl:when>
<xsl:otherwise>
<xsl:value-of
select="concat($thelabelprefix, ' and ', $txtlabels[$pos])"/>
</xsl:otherwise>
</xsl:choose>
</xsl:variable>
<xsl:value-of select="$thelabel"/>
<xsl:text> : </xsl:text> <xsl:value-of select="$sum"/>
<xsl:text>
</xsl:text>
<!-- recursive call to sum up the ages -->
<xsl:if test="$pos lt number($count)">
<xsl:call-template name="addthem">
<xsl:with-param name="count" select="$count"/>
<xsl:with-param name="pos" select="$pos + 1"/>
<xsl:with-param name="sum" select="number($sum) + number($elements[$pos + 1]/#age)"/>
<xsl:with-param name="elements" select="$elements"/>
</xsl:call-template>
</xsl:if>
</xsl:template>
</xsl:stylesheet>
produces following output for your input xml:
first : 20
first and second : 60
first second and third : 90
first second third and fourth : 170
I have added comments inside, let me know if you need further help.
It basically uses two recursive templates one each for the 'labels' and other for the addition.
And, Your sample output should read 90 and 170 instead of 110 and 190 or your sample input should say age=50 instead of age=30

Answer 2

The following short stylesheet produces exactly the output you first asked for, including the ordinal numbers:
Stylesheet:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema" exclude-result-prefixes="xs"
version="2.0">
<xsl:output method="text"/>
<xsl:template match="/" >
<xsl:for-each select="people/man">
<xsl:for-each select=".|preceding-sibling::man">
<xsl:value-of select="if (position() = last() and last() != 1)
then ' and ' else ' '"/>
<xsl:number format="w" ordinal="yes"/>
</xsl:for-each>
<xsl:text> age </xsl:text>
<xsl:if test="position() > 1">(combined)</xsl:if>
<xsl:value-of select="':', sum((.|preceding-sibling::man)/#age), '
'"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
Output:
first age : 20
first and second age (combined): 60
first second and third age (combined): 90
first second third and fourth age (combined): 170

Answer 3

A simple, non-recursive solution that is suitable for incremental sums of small sequence of sibling-elements:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text"/>
<xsl:strip-space elements="*"/>
<xsl:template match="man">
<xsl:value-of select=
"sum(#age|preceding-sibling::man/#age)"/>
<xsl:text>
</xsl:text>
</xsl:template>
</xsl:stylesheet>
When applied to the provided XML document (corrected to be made well-formed):
<people>
<man age="20" />
<man age="40" />
<man age="30" />
<man age="80" />
</people>
the wanted, correct result is produced:
20
60
90
170
II. An easy and efficient solution for huge sequences (node-sets) is the following, using the scanl template/function from FXSL:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:f="http://fxsl.sf.net/"
xmlns:myAdd="f:myAdd" xmlns:myParam="f:myParam"
>
<xsl:import href="scanl.xsl"/>
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<myAdd:myAdd/>
<myParam:myParam>0</myParam:myParam>
<xsl:template match="/">
<xsl:variable name="vFun" select="document('')/*/myAdd:*[1]"/>
<xsl:variable name="vZero" select="document('')/*/myParam:*[1]"/>
<xsl:call-template name="scanl">
<xsl:with-param name="pFun" select="$vFun"/>
<xsl:with-param name="pQ0" select="$vZero" />
<xsl:with-param name="pList" select="/*/*/#age"/>
</xsl:call-template>
</xsl:template>
<xsl:template match="myAdd:*" mode="f:FXSL">
<xsl:param name="pArg1" select="0"/>
<xsl:param name="pArg2" select="0"/>
<xsl:value-of select="$pArg1 + $pArg2"/>
</xsl:template>
</xsl:stylesheet>
Out of the box this easy solution (just call a template -- no recursive code to write) produces the wanted result:
<el>0</el>
<el>20</el>
<el>60</el>
<el>90</el>
<el>170</el>