$title Example: Redoing Fibonacci example using conditional assignments and ORD() $onuellist set I / A, B, 1*20 /; variable x(I), dummy_cost; equation fibonacci(I) objective; fibonacci(I).. x(I) =e= (x(I-1)+x(I-2))$(ord(I) > 2) + 1$(ord(I) <= 2); objective.. dummy_cost =e= 0; model fib /all/; solve fib using lp minimizing dummy_cost; display x.l;