Q: Say a vector A has ten values (decision variables) Objective: Maximize the sum of A. How do I model this constraint: The sum of consecutive four elements in the vector should be less than 10.
You can use the lag and lead operator as in the following example:
Set i /1*10/; Alias (i,j); Set iconseq(i,j); Scalar cnt; loop(i, for(cnt=0 to 3, iconseq(i,i+cnt) = yes)); display iconseq; Variable x(i); Equation e(i); e(i).. sum(iconseq(i,j), x(i)) =l= 10;
If you want your constraint to interpret “consecutive” in a circular manner, you will have to replace
+ in the
++ like this:
loop(i, for(cnt=0 to 3, iconseq(i,i++cnt) = yes));