Finding maximum value from nodeset with Xpath?

[golcarlad]

How do I return the maximum value for each ecoRule below using and Xpath expression? So for the first nodeset, I would get 10, and the second 9.
I used xpath code like this as a pure guess but it doesnt work - any ideas...(by the way Im programming in C#)

_doc.SelectNodes("//ecoRule[@name='"+ ecoRuleName +"']/max(scoreRule[@points])");

XML......below

<ecoRules>
 <ecoRule name="Something Else">
     <scoreRule type="ADJACENT" points="5" /> 
     <scoreRule type="CONTAINED" points="10" /> 
 </ecoRule>
 <ecoRule name="Adjacent">
     <scoreRule type="ADJACENT" points="3" /> 
     <scoreRule type="ADJACENT" points="9" /> 
     <scoreRule type="ADJACENT" points="7" /> 
   </ecoRule>
</ecoRules>

 

[k5tm]

Have you tried:

_doc.SelectNodes("//ecoRule[@name='"+ ecoRuleName +"']/max(scoreRule/@points)");

?

Tom Morrison

http://www.liant.com

 

[golcarlad]

Hi,

Tried that - but I get the "Invalid Token" error....

 

[k5tm]

Yes of course, because max is not a valid XPath function.

Trying again...

//ecoRule[@name='"+ ecoRuleName +"']/scoreRule[not(preceding-sibling::scoreRule/@points > @points or following-sibling::scoreRule/@points > @points)]

This should select the scoreRule node that does not have any sibling that has a points attribute value greater than the points attribute value of the selected node.

Clear?

Tom Morrison

http://www.liant.com

 

[k5tm]

Of course, if you want the value of the points attribute, slightly modify the above as follows:

//ecoRule[@name='"+ ecoRuleName +"']/scoreRule[not(preceding-sibling::scoreRule/@points > @points or following-sibling::scoreRule/@points > @points)]/@points

Tom Morrison

http://www.liant.com

 

[k5tm]

earnshaw1943

Any results to report?