Thanks for for the clarification. I am thinking to use agenda group instead. At least it would let me activate Rule 2 from Rule 1 without passing any parameters. However, I am struggling to understand the following example. Would it end after printing person name in rule HelloMr or get in a loop, Because, agenda group work on stacking the rules. thanks -------------------------------- rule "MrFlow" when person : Person ( gender == 'M'); then System.out.println("Mr flow activated"); drools.setFocus("MrGroup"); end rule "HelloMr" agenda-group "MrGroup" when person : Person (); then System.out.println("Hello Mr. " + person.getName()); retract (person); end -- View this message in context: http://drools.46999.n3.nabble.com/function-in-drools-tp4020021p4020028.html Sent from the Drools: User forum mailing list archive at Nabble.com.

Is there any way that I assigned a value to a variable in Rule 1 and then use the same variable in rule 2 thanks -- View this message in context: http://drools.46999.n3.nabble.com/function-in-drools-tp4020021p4020041.html Sent from the Drools: User forum mailing list archive at Nabble.com.

could you please help me how to do that in the following example. I will be extremely thankful rule "MrFlow" when person : Person ( gender == 'M'); then Number( doubleValue > $max ) from accumulate( SensorReading( $temp : temperature ) over window:time( 10m ), average( $temp ) ) // I want to use this $temp variable in rule "HelloMr" . what statement can i use here to do that drools.setFocus("MrGroup"); end rule "HelloMr" agenda-group "MrGroup" // How can use the $temp here.please give me an example when person : Person (); then System.out.println("Hello Mr. " + person.getName()); retract (person); end -- View this message in context: http://drools.46999.n3.nabble.com/function-in-drools-tp4020021p4020044.html Sent from the Drools: User forum mailing list archive at Nabble.com.

First of all many thanks for helping me here. I completely agree with you that I need to look into the basics. I will definitely start with drools manual and examples. coming back to the example which may not make a complete sense; I have a deadline to meet and therefore, I dont have much time to look around. I really appreciate your efforts for explaining my example. Basically, This is what I am trying to achieve rule 1 should check a condition and then perform the average. It also retrieve a threshold from a class (just to show that). It then jump to rule 2 and thats why I used the agenda group. rule 2 should only compare the average and the threshold. It should have access to the average and the threshold. That is why i thought of inserting them as facts in the first rule. could you please look into the code below and give me further advise. much appreciated declare parameters avg:double end rule "one" $pers : person : Person( gender == 'M' ) // why $pers : person and not only $pers accumulate ( SensorReading( $temp : temperature ) over window:time( 10m ), $avg : average( $temp ); then insertLogical( /*$pers,*/ new AverageTempRecord( $avg ) ); // could you please explain this. How exactly it should appear drools.setFocus ("Two"); end rule "two" //should only compare avg>threshold agenda-group "Two" $p : Person() // I want threshold here $a : AverageTemperatureRecord( /* pers == $p, */ $avg : avg ) then end -- View this message in context: http://drools.46999.n3.nabble.com/function-in-drools-tp4020021p4020047.html Sent from the Drools: User forum mailing list archive at Nabble.com.

Ok, so you may need something like this: 1) You need a bean to store the parameter. You can declare it in DRL, or use a normal java class and insert the instance from the main. The DRL version would be this: declare Parameters threshold : double end rule "Initialize" salience 9999 // fire first! when then insert( new Parameters( 10.0 ) ); // your value here end Or, you can set a global: // in java: kSession.setGlobal( "threshold", 1.0 ); // in DRL, at the beginning: global Double threshold; 2) You need rule "one" and something to hold your current average temperature: ( ps. sorry, the $pers : person : Person() was a typo! :) ) Now: do you need to relate the temperature to the person? I mean, how many Person are there in your workingmemory? I guess one, also considering that the SensorReading are not related to the person... In any case, here Person is acting as an "enabler fact" or "guard" which effectively decides if the rule is applicable or not. So: declare AverageTemperatureRecord // again, this or a java class value : double end rule "one" $pers : Person( gender == 'M' ) accumulate ( SensorReading( $temp : temperature ) over window:time( 10m ), $avg : average( $temp ); then insertLogical( new AverageTempRecord( $avg ) ); end Notice the use of "insertLogical" : your average will change over time (but see my remark about rule 2 below), so you may want to keep only the latest value, or a "history" with all of them? InsertLogical will make sure that a fact is retracted when its conditions no longer hold, and in case of an accumulate this is done when the aggregation set changes, i.e. whenever a SensorReading slides in or out of the window... The net effect is that the latest will take the place of the previous, which is different from keeping them all in memory, or keeping one an modifying it every time - all behaviours that can be obtained with slightly different rules. 3) Now you can write rule two: If you have the parameter object: rule "two" Parameters( $max : threshold ) $a : AverageTemperatureRecord( $avg : avg> $max ) then // do something end or you can use the global : rule "two with global " $a : AverageTemperatureRecord( $avg : avg> threshol ) then // do something end notice that your previous rule rule "two - previous" $p : Person( gender == 'M' ) Parameters( $max : threshold ) $a : AverageTemperatureRecord( $avg : avg> $max ) then // do something retract( $p ); end This rule - which does not need an agenda group - will be EVALUATED for every new AvgTempRecord (insertLogical will make sure that only the last remains in the WM, but this will not affect the evaluations: every ATR will be checked). [ Notice that this is not a "call", but a producer-consumer relation mediated by the working memory. Rule one generates some data and drops them into a common environment. Rule two "picks it up" and sees whether it matches its conditions or not. You WOULD probably need the agenda-groups if other sources could generate the ATRs for rule "two", but here rule "two" can only be activated after rule "one" has fired, producing the necessary fact] If at some point the > constraint is satisfied, the rule will be ACTIVATED and then FIRED. If the consequence retracts $p, as you were doing, the guard patterns will no longer satisfied and rule "one" (and two) will not be activated anymore. On 09/28/2012 11:01 AM, thano wrote: