I'm assuming that c6066 is really a number and not a string....if not you will need to change this to parse the string into a number. I think something like this should do it.  You first get the list from a SegmentGroup8 then sum the values you need. This is untested code. $seg: SegmentGroup8() $sum: Number() from accumulate( $cntTotal: ControlTotal() from $seg.getCnt(), sum($cntTotal.getC6066())) ________________________________ From: pamerida <elpamm(a)hotmail.com&gt; To: rules-users(a)lists.jboss.org Sent: Tuesday, September 20, 2011 5:35 PM Subject: [rules-users] accumulate function Hi everyone, I have this scenario: I have assserted a few elements of the type "SegmentGroup8" into the working memory, this SegmentGroup8 class have inside a list called private List<ControlTotal> cnt; What I need to achieve is to perform a "sum" of one of the fields called c6066 inside the ControlTotal for all the SegmentGroup8 asserted into the WM... I would like to use the accumulate functions but I really dont know how, any help would be appreciated, thanks in advance... the classes code is the following... public class SegmentGroup8     implements Serializable {     private List<ControlTotal> cnt;     private List<MonetaryAmount> moa; public List<ControlTotal> getCnt() {         return cnt;     }     public void setCnt(List<ControlTotal> cnt) {         this.cnt = cnt;     } ...... } public class ControlTotal extends Segment     implements Serializable {     private String c6069;     private String c6066;     ........     public String getC6069() {         return c6069;     }     public void setC6069(String c6069) {         this.c6069 = c6069;     }     public String getC6066() {         return c6066;     }     public void setC6066(String c6066) {         this.c6066 = c6066;     } ......... } -- View this message in context: http://drools.46999.n3.nabble.com/accumulate-function-tp3353507p3353507.html Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

The total of just one SegmentsGroup8.... What about something like this:  $allGroups: ArrayList(  )     from accumulate( $seg: SegmentsGroup8(  ),       init( ArrayList controlTotals = new ArrayList(); ),       action( controlTotals.add($seg.getCnt()); ),       reverse( controlTotals.remove($seg.getCnt()); ),       result( controlTotals)     ) $sum: Number() from accumulate($cntTotal: ControlTotal() from $allGroups, sum($cntTotal.getC6066())) This might also work .. but I'm not sure $allGroups: List() from collect(SegmentsGroup8()) $sum: Number() from accumulate($cntTotal: ControlTotal() from $allGroups.getCnt(), sum($cntTotal.getC6066())) ________________________________ From: pamerida <elpamm(a)hotmail.com&gt; To: rules-users(a)lists.jboss.org Sent: Wednesday, September 21, 2011 11:43 AM Subject: Re: [rules-users] accumulate function Thanks for your reply Wendy, but I have a question, would that code get me the sum of all the SegmentsGroup8?, or will that give me the sum of each individual SegmentGroup8??, cause what I need is the sum of all the controltotal of all the segmentGroup8 asserted into the WM... thanks so much for your help... -- View this message in context: http://drools.46999.n3.nabble.com/accumulate-function-tp3353507p3355812.html Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users