Search found 66 matches

by Manassaldi
3 weeks ago
Forum: Syntax
Topic: Two Indexex [Maybe Alias problem]
Replies: 4
Views: 535

Re: Two Indexex [Maybe Alias problem]

Hi, the problem is in set k at the end of the equation: ...V_NEG*dm(j,k)/sum(jj,dm(jj,k)); This is the equation exactly like the one in the image: eq_margen_1(j) .. sum(p,is(j,p))+ sum(i,th(j,i)*Y(i,j)) - sum(k,dm(j,k)) =G= sum(jj, sum(p,is(jj,p))+ sum(i,th(jj,i)*Y(i,jj)) - sum(k,dm(jj,k)))*V_NEG*dm...
by Manassaldi
2 months ago
Forum: Syntax
Topic: Binary Matrix
Replies: 2
Views: 148

Re: Binary Matrix

Hi, you must specify that MM(i,k) is a binary variable.

Code: Select all

Binary Variable
MM(i,k) ;
Bye
by Manassaldi
2 months ago
Forum: Archive Google Group
Topic: maximum number of repetitions
Replies: 2
Views: 263

Re: maximum number of repetitions

Hi, I think this can work. Maybe it should be modified for a greater generality Bye! set i your set i /1*55/ n number of pattern /p1*p6/ j your set j /40,50,60/ pattern(n,j) pattern definition /p1.40,p2.50,p3.60,p4.40,p4.50,p5.40,p5.60,p6.50,p6.60/ ; table D(i,j) 40 50 60 1 40 50 2 60 3 40 9 50 17 5...
by Manassaldi
2 months ago
Forum: Syntax
Topic: controling equations with subsets
Replies: 3
Views: 211

Re: controling equations with subsets

Hi, you must always reference to the original set (i, j) for example: set i /i1*i10/ j /j1*j15/ h /h1*h40/ technology(i,j) subset_of_tech(i,j) ; technology(i,j)= some set definition subset_of_tech(i,j)= some set definition constraint(i,j,h)$(technology(i,j) and subset_of_tech(technology)).. var(i,j,...
by Manassaldi
2 months ago
Forum: Modeling
Topic: Linearization problem with three decision variables
Replies: 1
Views: 113

Re: Linearization problem with three decision variables

Hello, do you need the product of three variables? If so, you can linearizing the product of two binary variables (Quality of production and Transportation area); this generate a new binary variable (suppose QT). Finally, you can linearizing the product of a binary and a continuous variable (QT and ...
by Manassaldi
2 months ago
Forum: Syntax
Topic: controling equations with subsets
Replies: 3
Views: 211

Re: controling equations with subsets

Hi, I hope this can help you.
Bye

constraint(technology)$subset_of_tech(technology).. var(technology) =g= par(technology);
by Manassaldi
3 months ago
Forum: Modeling
Topic: To binary or not to binary...
Replies: 4
Views: 247

Re: To binary or not to binary...

Hi, you can use a bounded continuous variable.
positive variable
T
;
T.lo=50;
T.up=150;

This works, except if you need that the variable take integer values.
Bye
by Manassaldi
4 months ago
Forum: Modeling
Topic: Xii >= Xij how to code in GAMS
Replies: 2
Views: 173

Re: Xii >= Xij how to code in GAMS

Hi, it's simple

set i warehouse /1*3/;
alias(i,j);

eq(i,j)$(ord(i) ne ord(j)).. X(i,i) =g= X(i,j);


Bye
by Manassaldi
5 months ago
Forum: Syntax
Topic: kind request: Setting two variables equal in GAMS
Replies: 1
Views: 162

Re: kind request: Setting two variables equal in GAMS

Hi,
what is J, K, RJ and KR?
Can you explain what each set means?

An alternative can be:

eq(J,K,RJ,KR)$(sameas(J,RJ) and sameas(K,KR)).. FlowMSAsMEN(J,K) =E= FlowMSAsREG(RJ,KR);

Bye
by Manassaldi
5 months ago
Forum: Syntax
Topic: logical equations & binary variables
Replies: 13
Views: 1216

Re: logical equations & binary variables

Hi, I think you can try a simple big-M reformulation. I assume that "HS(j)" is continuous and positive. The new variable TWC_HS(j) correspond to TWC(j)*HS(j) x(j) is a binary variable: x(j)=1 if HS(j) >=1000. x(j)=0 if HS(j) < 1000 eq1(j).. HS(j) =g= 1000*x(j); eq2(j).. TWC_HS(j) =g= 3.21*HS(j) - 3....