[Help-glpk] Expressing min function according to a boolean variable

[esma mehiaoui]

Hello,

 

Is it possible to express the function min according to a boolean variable?

 

For instance:

I have:

Set = {a,b,c,...} which represents the set of elements

par : is a parameter specified for each element

 

         par[a]=10;

         par[b]=10;

         par[c]=15;

 

var : is a boolean variable

        var (i,j) such as: i and j are in set and i!=j.

 

I would like to define a boolean variable for each element Y[i] (i in set) such as Y[i] = 1 if:

for each element j in set (i != j) if var [i,j] = 1 then par[i]< par[j].

Y[i] = 0 if there exists at least one element for which var [i,j] = 1 and par[j]< par[i].

 

 

Thank you in advance