set i set of MGs / 1,2,3 / t set of time intervals / 1*4 / ; Table p_pvf(i,t) 1 2 3 4 1 3.65 5.25 6.1 7 2 3.65 5.25 6.1 7 3 3.65 5.25 6.1 7 ; parameters c_pv(i) ; c_pv(i)=0.03; variables Eta(i) ; equation obj(i) ; obj(i).. Eta(i) =e= sum(t,p_pvf(i,t)*c_pv(i)); model subproblem /all/; solve subproblem minimizing Eta using mip;