Hello,   I got a problem with set defining since I am a beginner and I appreciate if somebody helps me here.   I have a data set as below Rank Person1 Next_person Money 1 A B 100 1 A B 120 2 A B 120 1 B C 110 1 B C 120 2 B C 120     I am skiping rest of the table here.   First column is rank of the person, second column is the person and the third column is the person next to person1. The last column shows the money person1 s. I already define this set in my optmodel:   set<num, str, num> rank_per_mny; rank_per_mny = [Rank Person1 Money]   Then I need to have kind of a product of this set with itself to give me a set as : {Rank,Person1,Money(for person1),Money(for Next_person)}   Basically, I want to add the next_person money to the previous set (for the same rank) and I think it is a product between this set and itself. For this example the set I need will be this: {1,A,100,110}, {1,A,100,120}, , {1,A,120,110}, , {1,A,100,120}, , {2,A,120,120},   I wrote the followingcode but I it does not get the correct values. Like it should start the Money for next_person from 110 but it starts from 100 again. I appreciate your help.   proc optmodel;   set<num, str, num> rank_per_mny; rank_per_mny = [Rank Person1 Money]; set<num, str,str, num> rank_per_mny_mny; rank_per_mny_mny = [Rank Person1 Next_person Money]; set< number> money; set< num, str, num > assign; set< num, str, num,number> cross;     for {< Rank, Person1, Next_person, Money > in rank_per_mny_mny } money = setof{< Rank Next_person Money > in rank_per_mny } Money ; assign = setof{< Rank Person1 Money > in rank_per_mny }{<Rank Person1 Money>; cross = cross union (assign cross price);   Thank you! ... View more

Hi,   In my optmodel, I have a binary variable which is defined on a set with 3 elements(c,d,v) as: P{c,d,v} I have another continous variable as x{c,d,v1,v2} which gives me 1 if P{c,d,v1}=1 and P{c,d,v2}=1 and 0 if one of them not , I defined it as   con variable_3{<c,d,v1,v2> in set3}: x[c,d,v1,v2] = P[c,d,v1]*P[c,d,v2]   What I did is: I built a big table which has all the combination of v1 and v2 as set3, this makes my problem huge and out of memory. I was wondering about these questions:   1. Does it make a difference if I use impvar instead of the constraint for the memory issue 2. I suspect that we can define set3 directly in the opmodel as a product of two other sets without generating a big table as a combination of v1 and v2. Can somebody help me if there is a way to do that.   Thank you so much!   ... View more