ampl: option show_stats 1; ampl: model steelpl5.mod; ampl: data steelpl5.dat; ampl: solve; Presolve eliminates 2 constraints and 2 variables. 12 piecewise-linear terms replaced by 24 variables and 12 constraints. Adjusted problem: 52 variables, all linear 24 constraints, all linear; 78 nonzeros 1 linear objective; 36 nonzeros. MINOS 5.4: optimal solution found. 27 iterations, objective 707991 ampl: