[AMPL 24840] Syntax error in Constraint

[Lam_Vy_Tran]

ComponentShipoutBalance{b in B: b <> ‘lowqfuel’,t in T: t>0}: #all of components produced are shippout

sum{i in I, j in J}u[i,j,t]*A[j,b,i] = u2[b,t];

There is something wrong in this part : {b in B: b <> ‘lowqfuel’,t in T: t>0}. I tried many different ways but did not work. Please help me!!!

[AMPL_Google_Group]

All of the indexing sets must be listed before the conditions:

ComponentShipoutBalance {b in B, t in T: b <> 'lowqfuel' and t>0}:
   sum {i in I, j in J} u[i,j,t] * A[j,b,i] = u2[b,t];