[rules-users] Drools 5.5 divide by 0 exception
Wolfgang Laun
wolfgang.laun at gmail.com
Fri Nov 1 14:24:20 EDT 2013
I haven't read a statement yet that says that, in Drools, LHS terms,
separated by a comma (!) must be executed in the order they are
written, or that the C/Java semantics for logical expression
evaluation is applied.
-W
On 01/11/2013, gboro54 <gboro54 at gmail.com> wrote:
> Could you expand upon why this is a poor practice? I assumed that if a part
> of the pattern doesn't match the expression evaluation is terminated
>
>
> laune wrote
>> I can anticipate the answer where OP says that there is a constraint
>> restricting argVolume to > 0. However, I don't think that independent
>> constraints such as we see them in this rule are evaluated as if they
>> were in a single logical expression, with Java semantics.
>>
>> The seductive possibility of binding to a half-baked expression (i.e.,
>> $ratio:(volumeAccumulations["total"]/consolidatdVolume.avgVolume))
>> should be discarded. This value can safely be computed on the RHS
>> where the denominator's value being !=0 is asserted.
>>
>> -W
>>
>> On 01/11/2013, Stephen Masters <
>
>> stephen.masters@
>
>> > wrote:
>>> Divide by zero exceptions usually occur when you try to divide by zero.
>>>
>>> So … first question … is consolidatdVolume.avgVolume ever zero?
>>>
>>>
>>> On 1 Nov 2013, at 16:17, gboro54 <
>
>> gboro54@
>
>> > wrote:
>>>
>>>> I have rules like the following:
>>>>
>>>> rule "Add Baseline to Context if it does not exists exists or not
>>>> greater
>>>> then 0"
>>>> no-loop true
>>>> when
>>>> $context:Context($id:id,baselineParticipation==null ||
>>>>
>>>> baselineParticipation.baselineRatio==null||baselineParticipation.baselineRatio==0)
>>>> then
>>>> modify($firm) {setBaselineParticipation(new
>>>> BaselineParticipation($id,new
>>>> BigDecimal(0.00485)))};
>>>>
>>>> end
>>>>
>>>> rule "Calculate Participation Ratio"
>>>> no-loop true
>>>> when
>>>>
>>>> $context:Context(consolidatdVolume!=null,consolidatdVolume.avgVolume>0,
>>>>
>>>> volumeAccumulations["total"]!=null,volumeAccumulations["total"]>0,
>>>>
>>>> $ratio:(volumeAccumulations["total"]/consolidatdVolume.avgVolume))
>>>> then
>>>> ConcurrentMap calculatedRatios=$firm.getCalculatedRatios();
>>>> calculatedRatios.put("fparticipationRatio",new BigDecimal($ratio));
>>>> modify($firm){setCalculatedRatios(calculatedRatios)};
>>>> end
>>>>
>>>> Despite the checks I get the following exception and any insight into
>>>> why
>>>> would be great:
>>>>
>>>> Exception executing consequence for rule "Calculate Firm Participation
>>>> Ratio" in com.nasdaq.rms.nq.status: java.lang.ArithmeticException: / by
>>>> zero
>>>> Exception executing consequence for rule "Calculate Firm Participation
>>>> Ratio" in com.nasdaq.rms.nq.status: java.lang.ArithmeticException: / by
>>>> zero
>>>> at
>>>> org.drools.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
>>>> at
>>>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1297)
>>>> at
>>>> org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1221)
>>>> at
>>>> org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1456)
>>>> at
>>>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:710)
>>>> at
>>>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:674)
>>>> at
>>>> org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:230)
>>>> at
>>>> com.nasdaq.fq.rms.workflow.processor.rules.PerformanceStatusAssignmentProcessor.doWork(PerformanceStatusAssignmentProcessor.java:156)
>>>> at
>>>> com.ften.ssr.workqueue.WorkItemRunnable.run(WorkItemRunnable.java:48)
>>>> at
>>>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
>>>> at
>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
>>>> at java.lang.Thread.run(Thread.java:724)
>>>> Caused by: java.lang.ArithmeticException: / by zero
>>>> at ConditionEvaluatorda6271cf5a744b6bbdb9c717cae2edb7.evaluate(Unknown
>>>> Source)
>>>> at
>>>> org.drools.rule.constraint.MvelConstraint.evaluate(MvelConstraint.java:200)
>>>> at
>>>> org.drools.rule.constraint.MvelConstraint.isAllowed(MvelConstraint.java:157)
>>>> at org.drools.reteoo.AlphaNode.modifyObject(AlphaNode.java:154)
>>>> at
>>>> org.drools.reteoo.CompositeObjectSinkAdapter.doPropagateModifyObject(CompositeObjectSinkAdapter.java:507)
>>>> at
>>>> org.drools.reteoo.CompositeObjectSinkAdapter.propagateModifyObject(CompositeObjectSinkAdapter.java:432)
>>>> at org.drools.reteoo.AlphaNode.modifyObject(AlphaNode.java:157)
>>>> at
>>>> org.drools.reteoo.CompositeObjectSinkAdapter.doPropagateModifyObject(CompositeObjectSinkAdapter.java:507)
>>>> at
>>>> org.drools.reteoo.CompositeObjectSinkAdapter.propagateModifyObject(CompositeObjectSinkAdapter.java:432)
>>>> at
>>>> org.drools.reteoo.ObjectTypeNode.modifyObject(ObjectTypeNode.java:314)
>>>> at
>>>> org.drools.reteoo.EntryPointNode.modifyObject(EntryPointNode.java:265)
>>>> at org.drools.common.NamedEntryPoint.update(NamedEntryPoint.java:483)
>>>> at org.drools.common.NamedEntryPoint.update(NamedEntryPoint.java:383)
>>>> at
>>>> org.drools.base.DefaultKnowledgeHelper.update(DefaultKnowledgeHelper.java:337)
>>>> at
>>>> com.nasdaq.rms.nq.status.Rule_Calculate_Firm_Participation_Ratio_cfb033f33c2b404fb2bff8e1b9af0175.defaultConsequence(Unknown
>>>> Source)
>>>> at
>>>> com.nasdaq.rms.nq.status.Rule_Calculate_Firm_Participation_Ratio_cfb033f33c2b404fb2bff8e1b9af0175DefaultConsequenceInvokerGenerated.evaluate(Unknown
>>>> Source)
>>>> at
>>>> com.nasdaq.rms.nq.status.Rule_Calculate_Firm_Participation_Ratio_cfb033f33c2b404fb2bff8e1b9af0175DefaultConsequenceInvoker.evaluate(Unknown
>>>> Source)
>>>> at
>>>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1287)
>>>> ... 10 more
>>>>
>>>>
>>>>
>>>> --
>>>> View this message in context:
>>>> http://drools.46999.n3.nabble.com/Drools-5-5-divide-by-0-exception-tp4026582.html
>>>> Sent from the Drools: User forum mailing list archive at Nabble.com.
>>>> _______________________________________________
>>>> rules-users mailing list
>>>>
>
>> rules-users at .jboss
>
>>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>
>>>
>>> _______________________________________________
>>> rules-users mailing list
>>>
>
>> rules-users at .jboss
>
>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>
>>
>> _______________________________________________
>> rules-users mailing list
>
>> rules-users at .jboss
>
>> https://lists.jboss.org/mailman/listinfo/rules-users
>
>
>
>
>
> --
> View this message in context:
> http://drools.46999.n3.nabble.com/Drools-5-5-divide-by-0-exception-tp4026582p4026587.html
> Sent from the Drools: User forum mailing list archive at Nabble.com.
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
More information about the rules-users
mailing list