correcting...
You can't put the variable in the test sentence of the if-then-else.
On Sat, Apr 5, 2008 at 2:13 PM, Leandro Barcelos <[EMAIL PROTECTED]>
wrote:
> Jonathan,
>
> Try:
> maximize Anzahl : sum{i in PEOPLE} x[i];
>
> That's the same.
>
> The problem with your equation is that you can't put if-then-else in a
> linear equation
>
> cya
>
>
>
> On Sat, Apr 5, 2008 at 10:36 AM, Jonathan Klein <[EMAIL PROTECTED]>
> wrote:
>
> > Hi,
> >
> > i havbe a very simple Problem like this:
> >
> > set PEOPLE;
> > var x{i in PEOPLE} binary;
> > maximize Anzahl : sum{i in PEOPLE} (if x[i]==1 then 1 else 0);
> > data;
> > set LEUTE:=Hans Joachen Peter Klaus;
> > end;
> >
> > And i get the Error: operator preceding == has invalid type
> >
> > I know, that this problem doesn't make sense, but i have i somewhat more
> > complex problem in wich i get the same error:
> >
> >
> >
> >
> > # Berufsinformationstag
> >
> > set STUDENT;#i
> > set CHOICE;#j
> > set COURSE;#k
> > set GROUP;#l
> >
> > param Student_Choice {i in STUDENT, j in CHOICE} symbolic in COURSE;#
> > Welcher Schüler welche Wünsche hat
> > #param Course_Minimum {k in COURSE};#Wie viele Schüler eine
> > Veranstaltung minimal braucht
> > #param Course_Maximum {k in COURSE};#Wie viele Schüler eine
> > Veranstaltung haben darf
> > param Satisfaction {j in CHOICE};#für jeden wunsch die Menge, wie
> > glücklich er ist
> >
> >
> > var TimeTable{k in COURSE, l in GROUP}, binary;
> > var StudentDistribution {i in STUDENT, k in COURSE, l in GROUP} binary ;
> >
> > # wenn sich der schüler die aktuelle veranstaltung wünscht und in der
> > veranstaltung in dieser gruppe ist
> > maximize z: sum{i in STUDENT, l in GROUP, k in COURSE, j in CHOICE}
> > (if 1==StudentDistribution[i,k,l]
> > and k==Student_Choice[i, j]
> > then Satisfaction[k] else 0);
> >
> >
> >
> >
> >
> > So i have Students that are in different Courses, in 1 Course per Group.
> > They coose 6 Courses and will be in 4 (1 in each group). If they are in a
> > grout that the have choosen, they are happy.
> > So i have to check for every Choice of every Student in every Course in
> > every Group if the student is in this course in this group and if he had
> > choosen it. If so, he gets as much happiness as his choice had importance.
> >
> > At the end i need to know form every Student in which courses he ist an
> > which courses in which group have to take place, so i have choosen the
> > binary variables.
> >
> > I dont konw why the types should not match, because StudentDistribution
> > ist binary, so i can only be 0 or 1 an Student_Choice has to be a COURSE.
> >
> > I studiet the language reference manual for a long time and looked at
> > many examples with if/then/else but i still have no idea what i'm doing
> > wrong.
> >
> > PS: I use C++ for 5 years now, but im relativly new to GNU MathProg :(
> >
> > I would be very gald for every help.
> >
> > Jonathan
> >
> >
> > _______________________________________________
> > Help-glpk mailing list
> > [email protected]
> > http://lists.gnu.org/mailman/listinfo/help-glpk
> >
>
>
>
> --
> Leandro B. Barcelos
--
Leandro B. Barcelos
_______________________________________________
Help-glpk mailing list
[email protected]
http://lists.gnu.org/mailman/listinfo/help-glpk
