So the example I am working with is this: You have a Teacher object that stores a list of Rosters objects in each Roster is a list of Students objects each Student has a grade value How would I go about creating a rule to find all the students that got As for a given Teacher across all her Rosters? -- View this message in context: http://drools.46999.n3.nabble.com/creating-a-rule-regarding-an-element-of... 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

Continuing with this same example, How can I count the number of times a student has received an A across all the classes? I can get it to trigger each time a student appears in the rosters of 2 different teachers and that student has an A in both but I can't figure out how to track it across more then that. On Fri, Apr 5, 2013 at 4:50 AM, Stephen Masters <stephen.masters(a)me.com&gt; wrote: Just thought I'd mention that I hadn't replied to this, because it looks way too much like comp-sci homework. Not sure whether that's the same reason others haven't replied either. ;) A hint though to get you started. You can probably use something like... $student: Student(grade != null) from $roster … with a few lines before that to pick out the roster in a similar fashion. To understand it, check out the Drools Expert manual for the "from" operator for working with lists/collections. Steve On 3 Apr 2013, at 19:59, burmanator <alexburman(a)gmail.com&gt; wrote: > So the example I am working with is this: > You have a Teacher object > that stores a list of Rosters objects > in each Roster is a list of Students objects > each Student has a grade value > > How would I go about creating a rule to find all the students that got As > for a given Teacher across all her Rosters? > > > > -- > View this message in context: http://drools.46999.n3.nabble.com/creating-a-rule-regarding-an-element-of... > 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 _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users -- Sincerely, Alex Burman cell: 908-672-0198 _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

So right now I have this: $teach1 : Teacher($level : Level, $rosters1 : Rosters) $roster1 : Roster($subject : Subject) from $rosters1 $teachs : ArrayList () from collect ( Teacher(Level == $level) ) Teacher($rosters2 : Rosters) from $teachs $rosts : ArrayList() from collect ( $roster2 : Roster(Subject != $subject) from $rosters2) I am trying to make a list of all the rosters for different subjects at the same grade level, however I am only getting rosters for 1 teacher at a time. I realize this is most likely due to the 2nd to last line but I'm not sure how to get around that. Any thoughts are helpful. On Thu, Apr 11, 2013 at 1:44 PM, Stephen Masters <stephen.masters(a)me.com&gt;wrote: > Look up "Conditional Element collect" in the manual. That provides > example > code for getting a list of matching facts. > > For more complex tasks, there's "accumulate". > > Steve > > > On 11 Apr 2013, at 17:51, Alex Burman <alexburman(a)gmail.com&gt; wrote: > > Continuing with this same example, How can I count the number of times a > student has received an A across all the classes? > > I can get it to trigger each time a student appears in the rosters of 2 > different teachers and that student has an A in both but I can't figure > out > how to track it across more then that. > > > On Fri, Apr 5, 2013 at 4:50 AM, Stephen Masters > <stephen.masters(a)me.com&gt;wrote: > >> Just thought I'd mention that I hadn't replied to this, because it looks >> way too much like comp-sci homework. Not sure whether that's the same >> reason others haven't replied either. ;) >> >> A hint though to get you started. You can probably use something like... >> >> $student: Student(grade != null) from $roster >> >> … with a few lines before that to pick out the roster in a similar >> fashion. >> >> To understand it, check out the Drools Expert manual for the "from" >> operator for working with lists/collections. >> >> Steve >> >> >> On 3 Apr 2013, at 19:59, burmanator <alexburman(a)gmail.com&gt; wrote: >> >> > So the example I am working with is this: >> > You have a Teacher object >> > that stores a list of Rosters objects >> > in each Roster is a list of Students objects >> > each Student has a grade value >> > >> > How would I go about creating a rule to find all the students that got >> As >> > for a given Teacher across all her Rosters? >> > >> > >> > >> > -- >> > View this message in context: >> http://drools.46999.n3.nabble.com/creating-a-rule-regarding-an-element-of... >> > 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 >> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> > > > > -- > Sincerely, > Alex Burman > cell: 908-672-0198 > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > -- Sincerely, Alex Burman cell: 908-672-0198