<root>
	<row q="w1" income="1"/>
	<row q="w" income="20"/>
	<row q="w1" income="300"/>
	<row q="w" income="4000"/>
	<row q="w1" income="50000"/>
	<row q="w" income="600000"/>
	<row q="w1" income="7000000"/>
	<row q="w" income="80000000"/>
	<row q="w1" income="900000000"/>
</root>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
	<xsl:output method="text"/>
	<xsl:template match="/">
		<xsl:call-template name="sumByGroup1">
			<xsl:with-param name="currnode" select="root/row[2]"/>
			<xsl:with-param name="grpfieldname" select="'q'"/>
			<xsl:with-param name="grpfieldvalue" select="'w'"/>
			<xsl:with-param name="resfieldname" select="'income'"/>
			<xsl:with-param name="res" select="0"/>
		</xsl:call-template>
		<xsl:text>-</xsl:text>
		<xsl:call-template name="sumByGroup1">
			<xsl:with-param name="currnode" select="root/row[1]"/>
			<xsl:with-param name="grpfieldname" select="'q'"/>
			<xsl:with-param name="grpfieldvalue" select="'w1'"/>
			<xsl:with-param name="resfieldname" select="'income'"/>
			<xsl:with-param name="res" select="0"/>
		</xsl:call-template>
	</xsl:template>
	<xsl:template name="sumByGroup1">
		<xsl:param name="currnode"/>
		<xsl:param name="grpfieldname"/>
		<xsl:param name="grpfieldvalue"/>
		<xsl:param name="resfieldname"/>
		<xsl:param name="res"/>
		<xsl:variable name="curvalue" select="translate($currnode/@*[name() = $resfieldname],',','.')"/>
		<xsl:variable name="curnumber">
			<xsl:choose>
				<xsl:when test="$curvalue!=''">
					<xsl:value-of select="$curvalue"/>
				</xsl:when>
				<xsl:otherwise> 0 </xsl:otherwise>
			</xsl:choose>
		</xsl:variable>
		<xsl:choose>
			<!--<xsl:when test="count($currnode/following-sibling::Row[@Group=$fieldvalue])>0"> -->
			<!-- <xsl:when test="count($currnode/following-sibling::Row[@Group=$grpfieldvalue])>0"> -->
			<xsl:when test="count($currnode/following-sibling::row[@*[name() = $grpfieldname] = $grpfieldvalue])>0">
				<xsl:call-template name="sumByGroup1">
					<xsl:with-param name="currnode" select="$currnode/following-sibling::row[@*[name() = $grpfieldname] = $grpfieldvalue][1]"/>
					<xsl:with-param name="grpfieldname" select="$grpfieldname"/>
					<xsl:with-param name="grpfieldvalue" select="$grpfieldvalue"/>
					<xsl:with-param name="resfieldname" select="$resfieldname"/>
					<xsl:with-param name="res" select="$res + number($curnumber)"/>
				</xsl:call-template>
			</xsl:when>
			<xsl:otherwise>
				<xsl:value-of select="$res+number($curnumber)"/>
			</xsl:otherwise>
		</xsl:choose>
	</xsl:template>
</xsl:stylesheet>

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