How can I write objective function with variable plus constant for solving using intlinprog Ex. X1+4

How can I write objective function with variable plus constant for solving using intlinprog Ex. X1+4

Thank you for your time

Answer 1

[Matt J]

There is no way to include a constant term in the objective function, but it would be meaningless to do so. Adding a constant term does not change the optimal solution, x.

[Nurye Hassen]

The original question is to minimize delay of trains, meaning actual arrival time minus scheduled arrival time. I considered the controlled variable to be actual arrival time and scheduled time table as a constant. Also, Is it acceptable to replace the constant with the variable in the objective and then include it in equality constraint like this.. obj X1+4 ==>x1+x2 Include x2=4; In constraints

Thank you again.

[Matt J]

Again, that would complicate things unnecessarily. Using your example of obj X1+4, note that

min{X1+4} = min{X1}+4

In other words, you could just solve the minimization min{X1} without any constant terms and then add 4 to the final result.

Answer 2

[Aurele Turnes]

If you have R2017b, the new Problem-based approach lets you specify constant terms in the objective of linear and mixed-integer linear problems. Although Matt is correct that the constant term will not change the final solution value, just the objective value.

[Nurye Hassen]

Very much helpfull! thanks. Aurele Turnes and matt.