* Shitkovski AMPL model (translation to GAMS) $Set N 2 Set I /1,%N%/; Variable X[I] , f ; Equation Eq_1,Def_obj; Eq_1.. x['2']-sqr(x['1']) =g= 0 ; Def_obj.. f =e= x['2'] ; x.lo['2'] = 0 ; x.l['1'] = 9; x.l['2'] = 100; Model s218 /all/; Solve s218 using nlp minimize f; display x.l; display f.l;