Originally posted by: SMABinAlIslam

Hi,

I am new in cplex. I need to know something. Maybe it is very easy, but I couldn't figure it out.

I am working with a model, that has a constraint:

g[i]+g[j]<=1

where i,j belongs to N={1,2,3,4}

if i = 1, j= {3,4}

if i=2, j={1,4}

if i= 3, j={1,2}

if j= 4, j= {2,3}

How can I represent it in Cplex?

Thanks in advance

Hi,

for example

{int} N={1,2,3,4};
 dvar boolean g[N];
 
 maximize sum(i in N) g[i];
 subject to
 {
  forall(i,j in N:
  (i==1) && (j in {3,4}) ||
  (i==2) && (j in {1,4}) ||
  (i==3) && (j in {1,2}) ||
  (i==4) && (j in {3,2})
  )
    g[i]+g[j]<=1;

}

regards

Originally posted by: SMABinAlIslam

Hi,

Thank you very much for the reply. It works.

Regards