Re: [rules-users] CEP + prevent consequences from triggering multiple times?
Hi Greg, Thanks for the response. Unfortunately your example doesn't appear to work, the SpeedIndicator doesn't get retracted, causing the consequence to only ever trigger once. However, I could add another rule to remove the SpeedingIndicator - meaning I no longer have to use the nasty global "state" object from my example. Any other suggestions greatly appreciated. Cheers, Paul On Thu, Dec 3, 2009 at 7:14 PM, Greg Barton wrote: > Have you tried truth maintenance? (i.e. insertLogical) > > rule "OverSpeedLimit" no-loop true > when > not SpeedingIndicator(); >$minSpeed : Double(doubleValue > 100) from accumulate( > $speedingEvent : SpeedingEvent ($speed : speed) >over window:time( 30s ) >from entry-point SpeedingStream, >min($speed) >); > then >insertLogical(new SpeedingIndicator()); > end > > Though I'm not sure this will work, because inserting the SpeedingIndicator > negates the first condition, probably causing the SpeedingIndicator to be > retracted automatically. :) But it's worth a try just to see if no-loop > would override that somehow. > > Apart from that, note that you can test the results of an accumulate in the > returned value. (The "Double(doubleValue > 100)" part.) YOu don't need the > eval. > > Also, where is the "state" object coming from? If it's a global, it's not > a good idea to use them in the conditions of your rules. Changes to them > are not tracked by the rete. > > --- On Thu, 12/3/09, reverselogic wrote: > > > From: reverselogic > > Subject: [rules-users] CEP + prevent consequences from triggering > multiple times? > > To: rules-users@lists.jboss.org > > Date: Thursday, December 3, 2009, 12:41 PM > > > > Hi, > > > > I'm trying to write a rule in drools, which triggers once > > some condition is > > active for a specified time interval. For example, if a > > vehicle is over a > > speed limit (100 mph) for 30 seconds, I want to trigger an > > action. However, > > once this rule has fired, I don't want it to fire again > > until the vehicle > > has dropped below the speed limit (and gone over the limit > > again). The only > > way I've managed to model this is by defining two rules; > > one for determining > > when the vehicle is speeding and one for determining when > > it is not speeding > > and using a global object to track the state of the vehicle > > (see rules > > below). > > > > rule "OverSpeedLimit" no-loop true > > when > > $minSpeed : Double() from accumulate( > > $speedingEvent : > > SpeedingEvent ($speed : speed) > > > > over window:time( 30s ) > > > > from entry-point SpeedingStream, > > min($speed) > > ); > > > > eval ($minSpeed > 100.0 && > > !state.speeding) > > then > > state.speeding = true > > end > > > > rule "!OverSpeedLimit" no-loop true > > when > > $speedingEvent : SpeedingEvent() > > from entry-point > > SpeedingStream > > eval ($speedingEvent.speed <= 100.0) > > then > > state.speeding = false > > end > > > > My questions is: Is there a better way to model the above > > behaviour, > > preferably as a single rule? The reason I ask is because I > > believe it would > > be too complicated for my users to define rules like this. > > Ideally, I would > > like to be able to create a DSL such as: "when Speed is > > above X for Y > > seconds then ..." > > > > Any help greatly appreciated. > > > > Thanks, > > > > Paul > > > > > > > > > > -- > > View this message in context: > http://n3.nabble.com/CEP-prevent-consequences-from-triggering-multiple-times-tp67424p67424.html > > Sent from the Drools - User mailing list archive at > > Nabble.com. > > ___ > > rules-users mailing list > > rules-users@lists.jboss.org > > https://lists.jboss.org/mailman/listinfo/rules-users > > > > > > > ___ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
Re: [rules-users] CEP + prevent consequences from triggering multiple times?
Have you tried truth maintenance? (i.e. insertLogical) rule "OverSpeedLimit" no-loop true when not SpeedingIndicator(); $minSpeed : Double(doubleValue > 100) from accumulate( $speedingEvent : SpeedingEvent ($speed : speed) over window:time( 30s ) from entry-point SpeedingStream, min($speed) ); then insertLogical(new SpeedingIndicator()); end Though I'm not sure this will work, because inserting the SpeedingIndicator negates the first condition, probably causing the SpeedingIndicator to be retracted automatically. :) But it's worth a try just to see if no-loop would override that somehow. Apart from that, note that you can test the results of an accumulate in the returned value. (The "Double(doubleValue > 100)" part.) YOu don't need the eval. Also, where is the "state" object coming from? If it's a global, it's not a good idea to use them in the conditions of your rules. Changes to them are not tracked by the rete. --- On Thu, 12/3/09, reverselogic wrote: > From: reverselogic > Subject: [rules-users] CEP + prevent consequences from triggering multiple > times? > To: rules-users@lists.jboss.org > Date: Thursday, December 3, 2009, 12:41 PM > > Hi, > > I'm trying to write a rule in drools, which triggers once > some condition is > active for a specified time interval. For example, if a > vehicle is over a > speed limit (100 mph) for 30 seconds, I want to trigger an > action. However, > once this rule has fired, I don't want it to fire again > until the vehicle > has dropped below the speed limit (and gone over the limit > again). The only > way I've managed to model this is by defining two rules; > one for determining > when the vehicle is speeding and one for determining when > it is not speeding > and using a global object to track the state of the vehicle > (see rules > below). > > rule "OverSpeedLimit" no-loop true > when > $minSpeed : Double() from accumulate( > $speedingEvent : > SpeedingEvent ($speed : speed) > > over window:time( 30s ) > > from entry-point SpeedingStream, > min($speed) > ); > > eval ($minSpeed > 100.0 && > !state.speeding) > then > state.speeding = true > end > > rule "!OverSpeedLimit" no-loop true > when > $speedingEvent : SpeedingEvent() > from entry-point > SpeedingStream > eval ($speedingEvent.speed <= 100.0) > then > state.speeding = false > end > > My questions is: Is there a better way to model the above > behaviour, > preferably as a single rule? The reason I ask is because I > believe it would > be too complicated for my users to define rules like this. > Ideally, I would > like to be able to create a DSL such as: "when Speed is > above X for Y > seconds then ..." > > Any help greatly appreciated. > > Thanks, > > Paul > > > > > -- > View this message in context: > http://n3.nabble.com/CEP-prevent-consequences-from-triggering-multiple-times-tp67424p67424.html > Sent from the Drools - User mailing list archive at > Nabble.com. > ___ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
[rules-users] CEP + prevent consequences from triggering multiple times?
Hi, I'm trying to write a rule in drools, which triggers once some condition is active for a specified time interval. For example, if a vehicle is over a speed limit (100 mph) for 30 seconds, I want to trigger an action. However, once this rule has fired, I don't want it to fire again until the vehicle has dropped below the speed limit (and gone over the limit again). The only way I've managed to model this is by defining two rules; one for determining when the vehicle is speeding and one for determining when it is not speeding and using a global object to track the state of the vehicle (see rules below). rule "OverSpeedLimit" no-loop true when $minSpeed : Double() from accumulate( $speedingEvent : SpeedingEvent ($speed : speed) over window:time( 30s ) from entry-point SpeedingStream, min($speed) ); eval ($minSpeed > 100.0 && !state.speeding) then state.speeding = true end rule "!OverSpeedLimit" no-loop true when $speedingEvent : SpeedingEvent() from entry-point SpeedingStream eval ($speedingEvent.speed <= 100.0) then state.speeding = false end My questions is: Is there a better way to model the above behaviour, preferably as a single rule? The reason I ask is because I believe it would be too complicated for my users to define rules like this. Ideally, I would like to be able to create a DSL such as: "when Speed is above X for Y seconds then ..." Any help greatly appreciated. Thanks, Paul -- View this message in context: http://n3.nabble.com/CEP-prevent-consequences-from-triggering-multiple-times-tp67424p67424.html Sent from the Drools - User mailing list archive at Nabble.com. ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
