Summing XML data that is in two arrays

Does the following do what you need it to?

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">  <xsl:output omit-xml-declaration="yes" indent="yes"/>  <xsl:template match="/">    <root>      <xsl:apply-templates select="//ItemCollection"/>    </root>  </xsl:template>  <xsl:template match="ItemCollection">    <xsl:variable name="itemCollection" select="." />    <xsl:variable name="itemsCount" select="count((.//IntensityArray)[1]//Intensity)" />    <xsl:for-each select="1 to $itemsCount">       <xsl:variable name="itemIndex" select="." />       <sum position="{$itemIndex}">         <xsl:value-of select="sum($itemCollection//IntensityArray//Intensity[$itemIndex])" />       </sum>    </xsl:for-each>  </xsl:template></xsl:stylesheet>

I got the following output when I ran it on your sample data:

<root>   <sum position="1">106.86959636211395</sum>   <sum position="2">154.70708847045898</sum>   <sum position="3">153.08208847045898</sum>   <sum position="4">267.8320999145508</sum>   <sum position="5">196.8874969482422</sum>   <sum position="6">149.74459838867187</sum>   <sum position="7">156.58208847045898</sum>   <sum position="8">236.7624969482422</sum>   <sum position="9">108.25000262260437</sum>   <sum position="10">126.6500015258789</sum>   <sum position="11">152.14999389648437</sum>   <sum position="12">105.65709751844406</sum>   <sum position="13">151.60709762573242</sum>   <sum position="14">188.74459838867187</sum>   <sum position="15">149.16250610351562</sum>   <sum position="16">137.14999389648437</sum>   <sum position="17">135.06958961486816</sum>   <sum position="18">163.8374900817871</sum>   <sum position="19">134.63208961486816</sum>   <sum position="20">143.03750228881836</sum>   <sum position="21">135.5749969482422</sum>   <sum position="22">148.48750686645508</sum>   <sum position="23">142.76250076293945</sum>   <sum position="24">132.5749969482422</sum>   <sum position="25">138.45709228515625</sum>   <sum position="26">165.68749618530273</sum>   <sum position="27">115.3000020980835</sum>   <sum position="28">107.92500567436218</sum>   <sum position="29">107.5500066280365</sum></root>

Updated:

Look at sum function, e.g.:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">  <xsl:output omit-xml-declaration="yes" indent="yes"/>  <xsl:key name="k" match="Intensity" use="count(preceding-sibling::Intensity)"/>  <xsl:template match="/">    <root>      <xsl:apply-templates select="//Intensity[generate-id(.) =                            generate-id(key('k', count(preceding-sibling::Intensity)))]"/>    </root>  </xsl:template>  <xsl:template match="Intensity">    <sum>      <xsl:value-of select="sum(key('k', count(preceding-sibling::Intensity)))"/>    </sum>  </xsl:template></xsl:stylesheet>

This template sums Intensity elements for both IntensityArray.

Output:

<root>  <sum>106.86959636211395</sum>  <sum>154.70708847045898</sum>  <sum>153.08208847045898</sum>  <sum>267.8320999145508</sum>  <sum>196.8874969482422</sum>  <sum>149.74459838867187</sum>  <sum>156.58208847045898</sum>  <sum>236.7624969482422</sum>  <sum>108.25000262260437</sum>  <sum>126.6500015258789</sum>  <sum>152.14999389648437</sum>  <sum>105.65709751844406</sum>  <sum>151.60709762573242</sum>  <sum>188.74459838867187</sum>  <sum>149.16250610351562</sum>  <sum>137.14999389648437</sum>  <sum>135.06958961486816</sum>  <sum>163.8374900817871</sum>  <sum>134.63208961486816</sum>  <sum>143.03750228881836</sum>  <sum>135.5749969482422</sum>  <sum>148.48750686645508</sum>  <sum>142.76250076293945</sum>  <sum>132.5749969482422</sum>  <sum>138.45709228515625</sum>  <sum>165.68749618530273</sum>  <sum>115.3000020980835</sum>  <sum>107.92500567436218</sum>  <sum>107.5500066280365</sum></root>

This transformation produces the wanted result even in cays the two node-sets have different number of nodes and/or some of the nodes in the 2nd node-set don't have value that is castable to a number:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output omit-xml-declaration="yes" indent="yes"/> <xsl:strip-space elements="*"/> <xsl:variable name="vArr1" select=   "/*/*/*/Item[1]/*/IntensityArray/*"/> <xsl:variable name="vArr2" select=   "/*/*/*/Item[2]/*/IntensityArray/*"/> <xsl:variable name="vShorterArr" select=  "$vArr1[not(count($vArr1) > count($vArr2))]  |   $vArr2[not(count($vArr2) >= count($vArr1))]  "/> <xsl:variable name="vLongerArr" select=  "$vArr2[not(count($vArr1) > count($vArr2))]  |   $vArr1[not(count($vArr2) >= count($vArr1))]  "/> <xsl:template match="/">     <summedIntensities>       <xsl:apply-templates select="$vLongerArr"/>     </summedIntensities> </xsl:template> <xsl:template match="Intensity">  <xsl:variable name="vPos" select="position()"/>  <Intensity>   <xsl:variable name="vVal2" select="$vShorterArr[position()=$vPos]"/>   <xsl:value-of select=     ".   +      concat('0',             substring($vVal2,                       1 div (number($vVal2) = number($vVal2))                       )             )     "/>  </Intensity> </xsl:template></xsl:stylesheet>

when this transformation is applied to the following XML document (the same as the provided one, but added to the first node-set one more Intensity element (the last one), to make the two node-sets different in size):

<out_xml>    <Root>        <ItemCollection>            <Item name="BaseLineOffSet" type="2">                <Histogram>                    <DispOrder>This is Order</DispOrder>                    <IntensityArray>                        <Intensity>105.84667205810547</Intensity>                        <Intensity>105.83854675292969</Intensity>                        <Intensity>105.57729339599609</Intensity>                        <Intensity>105.66104888916016</Intensity>                        <Intensity>105.56392669677734</Intensity>                        <Intensity>105.33917236328125</Intensity>                        <Intensity>105.33854675292969</Intensity>                        <Intensity>105.31544494628906</Intensity>                        <Intensity>105.40036010742187</Intensity>                        <Intensity>105.21470642089844</Intensity>                        <Intensity>105.14356994628906</Intensity>                        <Intensity>104.92792510986328</Intensity>                        <Intensity>104.93791961669922</Intensity>                        <Intensity>104.93979644775391</Intensity>                        <Intensity>104.96470642089844</Intensity>                        <Intensity>105.01107025146484</Intensity>                        <Intensity>104.76479339599609</Intensity>                        <Intensity>104.9085693359375</Intensity>                        <Intensity>104.70166778564453</Intensity>                        <Intensity>104.75499725341797</Intensity>                        <Intensity>104.77352905273437</Intensity>                        <Intensity>104.77714538574219</Intensity>                        <Intensity>104.59485626220703</Intensity>                        <Intensity>104.73235321044922</Intensity>                        <Intensity>104.35479736328125</Intensity>                        <Intensity>104.56911468505859</Intensity>                        <Intensity>104.38999938964844</Intensity>                        <Intensity>104.30992889404297</Intensity>                        <Intensity>104.37964630126953</Intensity>                        <Intensity>105.37964630126953</Intensity>                    </IntensityArray>                </Histogram>            </Item>            <Item name="DispIntervalsMaxValues" type="2">                <Histogram>                    <DispOrder>This is Order</DispOrder>                    <IntensityArray>                        <Intensity>1.0229243040084839</Intensity>                        <Intensity>48.868541717529297</Intensity>                        <Intensity>47.504795074462891</Intensity>                        <Intensity>162.17105102539062</Intensity>                        <Intensity>91.323570251464844</Intensity>                        <Intensity>44.405426025390625</Intensity>                        <Intensity>51.243541717529297</Intensity>                        <Intensity>131.44705200195312</Intensity>                        <Intensity>2.8496425151824951</Intensity>                        <Intensity>21.435295104980469</Intensity>                        <Intensity>47.006423950195312</Intensity>                        <Intensity>0.72917240858078003</Intensity>                        <Intensity>46.669178009033203</Intensity>                        <Intensity>83.804801940917969</Intensity>                        <Intensity>44.197799682617187</Intensity>                        <Intensity>32.138923645019531</Intensity>                        <Intensity>30.30479621887207</Intensity>                        <Intensity>58.928920745849609</Intensity>                        <Intensity>29.930421829223633</Intensity>                        <Intensity>38.282505035400391</Intensity>                        <Intensity>30.801467895507813</Intensity>                        <Intensity>43.710361480712891</Intensity>                        <Intensity>38.167644500732422</Intensity>                        <Intensity>27.842643737792969</Intensity>                        <Intensity>34.102294921875</Intensity>                        <Intensity>61.118381500244141</Intensity>                        <Intensity>10.910002708435059</Intensity>                        <Intensity>3.6150767803192139</Intensity>                        <Intensity>3.1703603267669678</Intensity>                    </IntensityArray>                </Histogram>            </Item>        </ItemCollection>    </Root></out_xml>

the wanted, correct result is produced:

<summedIntensisites>   <Intensity>106.86959636211395</Intensity>   <Intensity>154.70708847045898</Intensity>   <Intensity>153.08208847045898</Intensity>   <Intensity>267.8320999145508</Intensity>   <Intensity>196.8874969482422</Intensity>   <Intensity>149.74459838867188</Intensity>   <Intensity>156.58208847045898</Intensity>   <Intensity>236.7624969482422</Intensity>   <Intensity>108.25000262260437</Intensity>   <Intensity>126.6500015258789</Intensity>   <Intensity>152.14999389648438</Intensity>   <Intensity>105.65709751844406</Intensity>   <Intensity>151.60709762573242</Intensity>   <Intensity>188.74459838867188</Intensity>   <Intensity>149.16250610351562</Intensity>   <Intensity>137.14999389648438</Intensity>   <Intensity>135.06958961486816</Intensity>   <Intensity>163.8374900817871</Intensity>   <Intensity>134.63208961486816</Intensity>   <Intensity>143.03750228881836</Intensity>   <Intensity>135.5749969482422</Intensity>   <Intensity>148.48750686645508</Intensity>   <Intensity>142.76250076293945</Intensity>   <Intensity>132.5749969482422</Intensity>   <Intensity>138.45709228515625</Intensity>   <Intensity>165.68749618530273</Intensity>   <Intensity>115.3000020980835</Intensity>   <Intensity>107.92500567436218</Intensity>   <Intensity>107.5500066280365</Intensity>   <Intensity>105.37964630126953</Intensity></summedIntensisites>

Explanation:

1. Two variables are defined, each containing the nodes that comprize an "array".

2. Another two variables are defined: $vShorterArr, containing the shorter node-set and $vLongerArr containing the longer node-set.

3. Templates are applied to the longer node-set.

4. Each node in the longer node-set is summed with the corresponding (if such exists) node in the shorter node-set, or with 0, otherwise.

II. XSLT 2.0 solution:

<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xs="http://www.w3.org/2001/XMLSchema"> <xsl:output omit-xml-declaration="yes" indent="yes"/> <xsl:strip-space elements="*"/> <xsl:variable name="vArr1" select=   "/*/*/*/Item[1]/*/IntensityArray/*/number()"/> <xsl:variable name="vArr2" select=   "/*/*/*/Item[2]/*/IntensityArray/*/number()"/> <xsl:variable name="vShorterArr" select=  "if(count($vArr1) lt count($vArr2))     then $vArr1     else $vArr2  "/> <xsl:variable name="vLongerArr" select=  "if(count($vArr1) ge count($vArr2))     then $vArr1     else $vArr2  "/> <xsl:template match="/">     <summedIntensities>       <xsl:for-each select="$vLongerArr">          <xsl:variable name="vPos" select="position()"/>          <Intensity>           <xsl:variable name="vVal2" select=                "$vShorterArr[$vPos]"/>           <xsl:sequence select=             ".           +              (if($vVal2 castable as xs:double)                then $vVal2                else 0                )             "/>          </Intensity>       </xsl:for-each>     </summedIntensities> </xsl:template></xsl:stylesheet>

III. Using FXSL:

It is much easier to solve this problem using the f:zip-with() function/template of FXSL.

Below is a solution using FXSL 2:

<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:f="http://fxsl.sf.net/" exclude-result-prefixes="f">  <xsl:import href="../f/func-zipWithDVC.xsl"/>  <xsl:import href="../f/func-Operators.xsl"/>  <!-- To be applied on numList.xml -->  <xsl:output omit-xml-declaration="yes" indent="yes"/>  <xsl:template match="/">     <summedIntensities>      <xsl:for-each select=      "f:zipWith(f:add(),                 /*/*/*/Item[1]/*/IntensityArray/*/number(),                 /*/*/*/Item[2]/*/IntensityArray/*/number()                 )"      >       <Intensity>        <xsl:sequence select="."/>       </Intensity>      </xsl:for-each>     </summedIntensities>  </xsl:template></xsl:stylesheet>