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amplgurobi

AMPL - Express summation with max function

I need to declare this image in my .mod as "subject to" but i don't know how to do it. Can someone explain it to me? My main problem is max{0,t-4}.

here

I tried: 

    set ANY_INICI:=1..10;
    subject to constr{t in 1 .. 10}:
        sum {j in max(0,t-4)+1 .. ANY_INICI, i in t-j+1 .. 4} decisio[i,j]>=restriccio[t];
Solution

  • The correct form is:

    t iterates ANY_INICI and 1..10 is equal to ANY_INICI param

    subject to constr{t in ANY_INICI }:
        sum {j in max(0,t-4)+1..t, i in t-j+1..4} decisio[i,j] >= restriccio[t];